Where the method came from

By analogy to radio communication, we defined the theta oscillation to be a carrier wave whose modulation contains information.

Because position encoding is sparse, a theoretical result ( 14 ) based on compressed sensing ( 15 ) suggests that unsupervised learning can discover position-dependent sparse structure in the LFP without explicit knowledge of the rat’s position.

By analogy to radio communication, we defined the theta oscillation to be a carrier wave whose modulation contains information.

Because position encoding is sparse, a theoretical result ( 14 ) based on compressed sensing ( 15 ) suggests that unsupervised learning can discover position-dependent sparse structure in the LFP without explicit knowledge of the rat’s position.

Classically, information is the reduction of uncertainty among alternatives: when a coin falls on one of its two sides, it provides 1 bit of information, whereas a die falling on one of six faces provides ~2.6 bits.

Classically, information is the reduction of uncertainty among alternatives: when a coin falls on one of its two sides, it provides 1 bit of information, whereas a die falling on one of six faces provides ~2.6 bits.

Small-world networks have mostly local connectivity with comparatively few long-range connections. Augmented with hubs, such networks maximize interactions while minimizing wiring.

transfer entropy, a measure of directional interactions among brain areas, is balanced in the feedforward (green) and feedback (red) directions

If integration is lost (as in anesthesia or sleep), the die disintegrates into many two-faced dice, each generating 1 bit of information.

Those results are analogous to previous findings on literacy, showing that the acquisition of expertise in reading shifts the responses of left ventral visual cortex toward letters and away from faces

Second, we used representational similarity analysis to probe whether a similar pattern of activation was evoked, within each subject, by all math-related activities: i.e., mathematical reflection, calculation, and numbers or formula recognition.

This “rate-dependent” effect of AMPH recalls the widely observed pattern described in the Yerkes-Dodson law, which states that performance, especially in difficult tasks, initially increases with physiological or mental arousal, but when levels of arousal become too high, performance is degraded

The mouse is the pre-eminent mammalian model system for genetic labeling or manipulation of specific cortical cell classes (O'Connor et al., 2009 ). Cellular imaging in mice offers immense potential for understanding cortical function in healthy mice, as well as in mouse models of neurologic disease (e.g., Eichhoff et…

A useful measure of behavioral discriminability of targets from non-targets is given by d ′ = norminv(HR) − norminv(FA), where norminv() is the inverse of the cumulative normal function (Green and Swets, 1966 ). Values for HR and FA were truncated between 0.01 and 0.99. Higher d ′ values indicate better…

Excitatory neurons and inhibitory neurons could be classified in vivo in this mouse due to expression of green fluorescent protein in all GABAergic neurons (Figure 2 A, green neurons; Tamamaki et al., 2003 ; Sohya et al., 2007 ; Kerlin et al., 2009 ). An example of orientation-tuned responses to drifting gratings…

A local volume was loaded with a green synthetic calcium indicator (OGB1-AM), and astrocytes were co-loaded with sulforhodamine (SR101; Nimmerjahn et al., 2004 ), a red, calcium-insensitive fluorescent dye that generates a constant average fluorescence level in the absence of brain motion

SMT firing fields of both place cells and grid cells were similar to those of other cells and spanned the entire task, including periods when the rat was immobile ( Extended Data Fig. 10 ). Other spatial cell types, including border cells and head direction cells, were also SMT-modulated (e.g. cell 9 in Fig. 4b…

To detect place cells, we calculated “spatial information” 34 – the mutual information rate between spikes and location – using the same formula as above ( Eqn. 2 ), but using the 1600 spatial bins instead of time bins. Place cells were defined as cells for which the information rate exceeded 99% of the values for the…

To test this idea, we designed a “sound manipulation task” (SMT), in which rats changed the frequency of sound in their environment ( Fig. 1a ). Animals deflected a joystick to activate a pure tone produced by a sound speaker. They continued deflecting in order to increase frequency along a perceptually uniform…

However, the hippocampal/entorhinal circuit is involved not only in spatial navigation, but in a variety of memory-guided behaviors 6 . The relationship between this general function and the specialized spatial activity patterns is unclear. A conceptual framework reconciling these views is that spatial representation…

For each trial, bipolar derivations were analyzed in the time–frequency domain by convolution with complex Gaussian Morlet wavelets with a bandwidth parameter f 0 /σ f = 6, i.e., wavelets of approximately six cycles length.

Post hoc power analysis was done with Monte Carlo simulations.

Results were corrected for multiple comparisons using false discovery rate across all time windows and electrodes.

Neural timescales also increase across hierarchies of visual cortical areas, where it is quantified as the decay time constant ( τ ) of an exponential fit to the temporal spike count autocorrelation.

Neural timescales also increase across hierarchies of visual cortical areas, where it is quantified as the decay time constant ( τ ) of an exponential fit to the temporal spike count autocorrelation.

The protocol we introduce here was inspired by changes in cortical activity and perceptual awareness of complex repeating acoustic patterns in human subjects.

We then used a binary support vector machine (SVM) on the principal components projection to classify whether ensemble activity for each cycle came from the rhythmic or random stimulus context

To test the hypothesis that more attentional resources were devoted during difficult (low SNR) tasks than during easy (high SNR) tasks, we modified the task structure by randomly inserting probe trials (25%) of intermediate difficulty during a block of difficult or easy trials (75%). We reasoned that if detection…

In all these experiments, the pattern of STRF changes that emerged followed a simple model in which the acoustic features of the foreground were enhanced and those of the background suppressed, a hypothesis which we called a “contrast matched filter

It has been proposed that the primacy effect is due to the fact that items at early list positions undergo more extensive rehearsal than items presented later ( Rundus, 1971 ; Brodie and Murdock, 1977 ). This idea suggests a link between LTM formation and rehearsal processes, which are attributed to working memory

The SES criteria consisted of parental education, occupation, and family resources, which together represented SES better than any of these alone

Moyer and Landauer (1967) were the first to measure the RT in a selection paradigm by pressing the associated button. They found that participants made more mistakes and required more time when the two numbers to be compared were close (e.g., 7 vs. 9) than farther apart (e.g., 2 vs. 9). That is, there is a distance…

To explore this, we expressed the optogenetic excitatory channel oChIEF ( Lin et al. 2009 ) in layers 2 and 3 (L2 and L3) of medial entorhinal cortex (MEC) to study the impact of these inputs onto PCs and interneurons with cell bodies located in the SO of hippocampal CA1. The MEC was chosen as the viral expression…

To explore this, we expressed the optogenetic excitatory channel oChIEF ( Lin et al. 2009 ) in layers 2 and 3 (L2 and L3) of medial entorhinal cortex (MEC) to study the impact of these inputs onto PCs and interneurons with cell bodies located in the SO of hippocampal CA1. The MEC was chosen as the viral expression…

In addition to being important for normal brain function, the EC is one of the first regions in the brain to display neurodegeneration and dysfunction in Alzheimer’s disease (AD) ( Braak and Del Trecidi 2015 ). The initial pathology associated with AD is hallmarked by an accumulation of hyperphosphorylated tau protein…

Although the timing of action potentials in individual MEC L3 projection neurons do not correlate well with population EC theta field potentials, MEC L3 projection neurons do fire coherently with their own internal theta activity

The design and functional features of these next-generation chloride-conducting channelrhodopsins provide both chronic and acute timescale tools for reversible optogenetic inhibition, confirm fundamental predictions of the ion selectivity model

through iC++ activation will reduce excitability, just as seen with endogenous chloride-conducting channels such as GABA A receptors, providing efficient inhibition via shunting of excitatory inputs

Gene ontology and gene network analyses of differentially expressed genes revealed that genes up-regulated in the mPFC during associative memory encoding form a highly interconnected network involved in biological processes that promote synaptic plasticity and memory formation, including synthesis of cAMP…

Next, we used an in vivo optogenetic approach to permit real-time manipulation of excitatory mPFC neuronal activity in freely behaving mice.

An auditory perceptual object, like its visual counterparts, is defined by the binding of multiple sensory features, represents a source distinct from others in the scene, and is invariant over different sensory instances

Such associations have been found, with positive relationships between years of training and anterior hippocampal gray matter volume in musicians ( Groussard et al., 2014 , Groussard et al., 2010a ) and piano-tuners

This hypothesis predicts that sound-evoked activity in V1 should have the typical attributes of behavioral signals: low dimension 13 and a broad footprint 14 , 21 , 22 that extends beyond the cortex 13 . Moreover, sound-evoked activity should be independent of direct inputs from auditory cortex and should be…

We then identified the visual and auditory components of each neuron’s sensory response. A typical V1 neuron responded differently to different combinations of videos and sounds (Fig. 1a ). To characterize these responses, we used a marginalization procedure similar to factorial ANOVA. To measure the neuron’s…

The arrays of sound-related activity A , of video-related activity V and of audiovisual interactions I describe the activity of many neurons. To summarize this activity, we used cvPCA 15 . In this approach, principal component projections are found from one-half of the data, and an unbiased estimate of the reliable…

To estimate the extent of the fibers that were cut by the transectomy, we took advantage of the large-scale connectivity database of experiments performed by the Allen Brain Institute (Allen Mouse Brain Connectivity Atlas 26 , https://connectivity.brain-map.org/ ). Using custom Python scripts, we selected and…

We used viral transfection methods to selectively drive excitatory or inhibitory opsin expression in AC-IC projections.

To examine frequency selectivity of neurons, sparseness of frequency tuning was computed as:

The unbiased nature of this stimulus allowed us to estimate the spectro-temporal receptive field of neurons (STRF), which quantifies the dynamics of sound waveform in time and frequency that lead to a neuronal response.

This analysis can reveal whether changes in frequency selectivity are linear/subtractive, multiplicative/divisive, or some combination of these transformations.

However, the procedural parameters of the tasks used in primates and rodents are necessarily different. For example, the location of the eyes on the rat’s head prevents it from fixating a central point like primates. Instead, in the rat version of this task, subjects must maintain a nosepoke into a central port for…

The fact that PPC damage impaired discrimination after an extra dimensional shift suggests that it may be involved in attention that is required when the meaning of a stimulus has changed.

According to one influential theory ( Pearce & Hall, 1980 ), a CS will capture attention if its meaning surprisingly changes. This increase in attention to the CS enhances subsequent learning about that cue

Since psychedelics have been classified under Schedule I in the 1971 conventions of the United Nations 21 and remain illegal in many countries, observational studies such as anonymous online surveys have been used to assess the use, misuse and potential therapeutic properties of psychedelics

We then selected our population of interest based on OCD symptoms and kept for analyses the data from participants who had either a diagnosis of OCD performed by a health professional (n = 9), or an OCI-r score superior to 18 (n = 62) 29 or both (n = 103). The rationale was to include participants who had not been…

As Squire (2004) points out, the first theoretical approaches relevant to current neuroscience come from the 19th century. These include Maine de Biran (1804/1929) ( Maine de Biran, 1929 ) who, at the beginning of the century, wrote of mechanical memory, sensitive memory, and representative memory. The philosopher…

The importance of Pavlov (1927) and Fitts and Posner (1967) are especially noteworthy during the first two thirds of the 20th century. Pavlov’s studies are related to a type of memory that later would be called associative memory. Meanwhile, Fitts and Posner’s studies are considered the first model to explain…

The experimental modern era arguably began when Milner (1962) demonstrated, with HM experiments, that a seriously ill patient could acquire a new skill (hand-eye coordination) without any memory of having encountered the task before. “While this finding showed that memory is not unitary, discussions at the time tended…

Wang and Bellugi (1994) presented a genetically based test that supports the functional and anatomical separation of Baddeley’s model with phonological and visuospatial storehouses. They compared two genetic syndromes (Williams and Down) with different brain morphology. Williams syndrome patients, despite having…

However, rigorous psychophysical methods are not yet as developed for these rodents as they are for primates.

In SDT, one measures not only the rate of correct detections, but also the rate of false alarms: trials where the animal reported the stimulus or attribute was present when it wasn't. These rates yield a measure of detectability called d ', which is independent of criterion, and thus immune to its changes.

we used the light-sensitive bacteriorhodopsin Chlamydomonas reinhardtii channelrhodopsin-2 (ChR2), a cation channel activated by ~470 nm blue light

Largely through research with non-human primates, a foundation was developed for understanding the anatomic and functional organization of primary motor cortex and other motor-related areas ( Evarts, 1966 , 1967 , 1968b , 1968a ; Fetz, 1969 ; DeLong, 1971 ; DeLong and Strick, 1974 ; Tanji and Evarts, 1976 ; Weinrich…

Unlike the motor prosthesis approach in which the similarity between nonhuman primate M1 and human M1 is evident in the underlying anatomy (and, as now being demonstrated, physiology), the relationship between any given animal model of epilepsy and the various forms of human epilepsy is unclear.

First amongst these are new methods for extracting spiking information from large data sets. These ‘clustering’ algorithms are now available in a variety of different forms with optimization for high speed (essentially real-time) and for working with particularly large data sets.

Optogenetic enhancement and suppression of SOM-IN activity during training destabilized and hyper-stabilized spines, respectively, and both manipulations impaired the learning of stereotyped movements.

To address this issue, we expressed GFP-tagged Gephyrin, a postsynaptic scaffolding protein at inhibitory synapses, in L2/3 excitatory neurons using in utero electroporation

To target glutamatergic excitatory neurons, we used the Vglut2-Cre line (Fig. 2a ), as IC excitatory neurons express the Vglut2 but not Vglut1 28 . To target GABAergic inhibitory neurons, we used the VGAT-Cre line (Fig. 2b ), as glycinergic neurons, which also express VGAT, are absent from the IC

The mechanism of locomotion-related effects is still unclear. In the ACx, Zhou et al. found that the excitatory and parvalbumin-positive inhibitory neurons are inhibited by the cortical layer 1 (L1) neurons, while Schneider et al. 23 reported that inhibitory neurons are excited by motor cortex, which in turn inhibits…

What might be the source of the high-frequency selectivity seen in the IC shell L1 inhibitory neurons? Using two-photon-guided whole-cell recording, Geis and Borst revealed that the IC shell L1 inhibitory neurons that have large somas receive shorter first-spike latency excitatory inputs than other neurons 49 . Using…

It is worth noting that inhibitory neurons in the mouse SC superficial layers are also more direction selective than the excitatory neurons 41 , and the origin of the direction selectivity is the retina 51 . Inhibitory neurons in the IC shell and SC superficial layers project to the nonlemniscal thalamus and…

To achieve accurate simulations of light propagation close to the optical fiber, before the orientation of photon trajectories is randomized by multiple scattering events, we used an anisotropic scattering model with either Henyey-Greenstein or Gegenbauer kernel phase functions, as indicated below.

We therefore screened members of the cruxhalorhodopsin class in primary neuronal culture to identify molecules with both red-shifted action spectra and robust photocurrents ( Fig. 1a and Supplementary Fig. 2 ) and identified a hyperpolarizer we named Halo57, the cruxhalorhodopsin from H. salinarum (strain Shark), with…

We subsequently engineered Halo57 by identifying K200R and W214F point mutations 19 , 20 ( Fig. 1b ), which significantly boosted photocurrents without altering its red action spectrum ( n = 9 or 10 cells; P = 0.02, ANOVA with Dunnett’s post hoc test), and by appending the KGC 21 or ER2 (ref. 22 ) trafficking…

Because red light is less absorbed by hemoglobin than blue, green or yellow wavelengths, we reasoned this red-light sensitivity might render deep brain regions more accessible. We validated this through Monte Carlo modeling and direct measurement in the live mouse brain

Complementary blanks were presented on 50% of all trials, with 25% lightly masked and 25% heavily masked. This was to ensure equal numbers of stimulus and blank trials within each masking condition, for purposes of subtracting mask-blank-mask ERPs from mask-stimulus-mask ERPs.

During the no-report condition, participants were instructed to count how many times the green circle appeared during each 64-trial block, providing a three-alternative-forced-choice (3-AFC) button-press response at the end of each block to indicate four, six, or eight green circles (number of circles presented varied…

Because our hypotheses included the absence of a P3b in the no-report condition, we also conducted planned Bayesian analyses to determine whether our nonsignificant result was due to statistical insensitivity, or whether this result provides evidence in favor of the null hypothesis. First, we compared the mean voltage…

After the 15 blocks of each condition, participants were given an incidental memory test, to verify the manipulation of visibility via masking, regardless of the task. Accordingly, during these memory tests, participants were shown the eight visible (lightly masked) images, the eight heavily masked (invisible) images…

Such rhythms reflect the synchronized activity of large numbers of neurons because synchronous currents sum together to generate large-amplitude fluctuations in LFP, whereas non-synchronized currents do not sum together and thus remain too small to be detected.

Theoretical work has shown that the frequency of gamma rhythms generated by networks of hippocampal interneurons can vary depending on the strength of excitatory and inhibitory inputs 141 . Specifically, in simulations of gamma activity in a model neuron network, gamma frequency was found to increase with increased…

In addition to providing specific insights regarding the development of connectivity onto Re + interneurons, our findings suggest that monosynaptic tracing using the rabies virus provides an effective method for determining the afferent connectivity of cortical neurons at different developmental time points.

These observations emphasize that understanding how brain wiring is achieved will require a case-by-case examination of how different cell types and the cortical microcircuits they contribute to are assembled.

BDM is widely used in behavioural economics and neuroeconomics to elicit non-strategic reservation prices also known as willingness-to-pay (WTP).

In contrast, the field of perceptual decision-making has highlighted the fact that confidence can be measured independently of the choice process itself

In contrast, the field of perceptual decision-making has highlighted the fact that confidence can be measured independently of the choice process itself 9 , 10 , where it is conceptualized as reflecting a “second-order” metacognitive evaluation. Critically, dissociating confidence from other features of the decision…

To establish value for individual items we asked participants at the end of the scanning session to place a bid for each food item using a standard incentive compatible procedure, the Becker–DeGroot–Marschak (BDM) mechanism 15 . BDM is widely used in behavioural economics and neuroeconomics to elicit non-strategic…

We adapted a race model 7 , 21 wherein evidence in favor of each option (the snacks presented on the left and right side of the screen) is accumulated over time and the decision is made on the basis of the first option to reach a threshold ( Figure 2b ). In this model confidence is defined as the absolute difference…

The precise AM and ∆BW values used during recording sessions were tailored to each subject’s psychophysical thresholds for detection of each sound feature (AM and ∆BW) in isolation, determined prior to recording.

To demonstrate a possible causative role of defunct PV neurons in the generation of TLE, we permanently inhibited GABA release selectively from PV neurons of the ventral subiculum by injecting a viral vector expressing tetanus toxin light chain in male mice. Subsequently, mice were subjected to telemetric EEG…

At this point, we asked whether already transient inhibition of GABA release from PV-containing interneurons would be sufficient to induce C-SWDs and SRSs. We therefore injected PV-cre mice into the ventral subiculum with AAV vector-expressing hM4Di receptors (AAV -hM4Di ), which are exclusively activated by designer…

However, when we applied the CB1 receptor agonist WIN 55,212–2 to suppress GABA release from non-PV, cholecystokinin (CCK)-containing basket cells we observed, consistent with a previous report on CA1 neurons ( Murray et al., 2011 ), that the amplitude of the WIN 55,212–2-insensitive component of the eIPSC…

Interestingly, PV-containing interneurons are preferentially lost in the subiculum of patients with TLE even without Ammon's horn sclerosis ( Andrioli et al., 2007 ). Also in animal models of TLE, PV-containing interneurons of the subiculum selectively degenerate after an initial status epilepticus ( Dinocourt et al…

This would enable the hippocampal network to represent four to eight items per theta cycle (corresponding to the number of nested gamma cycles), which has been related (Lisman and Idiart, 1995 ) to the “magic number” of 7 ± 2 items that humans can typically hold in short term memory (Miller, 1956 ).

A parallel can be made with fRMI studies showing robust and consistent activation patterns in response to similar stimuli, despite the low temporal and spatial resolution of the technique (Guest and Love, 2017 ). Thus, while certain types of computation can still be detected or elicited even without having access to…

The detuned oscillators model was originally proposed by O'Keefe and Recce ( 1993 ) in their initial report of phase precession, and remains one of the most elegant hypotheses to date 1 ( Figure 3A ). This model considers a place cell that oscillates at a slightly faster frequency than theta. These two oscillators…

In the network connectivity models , contrary to the above cellular models in which no particular synaptic connectivity is assumed, phase precession results from transmission delays between asymmetrically connected cells ( Figure 3C ; Jensen and Lisman, 1996 ; Skaggs et al., 1996 ; Tsodyks et al., 1996 ; Romani and…

acoustic features well known to stimulate distinct ventral (“what”) and dorsal (“where”) neural pathways in humans

The HRTF coefficients were individually determined by a brief sound localization task at the beginning of the experiment. On each trial, 1 of the 4 vowels was presented at 1 of the 5 azimuth locations (i.e., −90°, −45°, 0°, 45°, 90°) using a variety of HRTF coefficients selected from the TDT library that best suited…

For instance, changes in the receptive fields of ferret auditory cortex can occur within minutes of a tone discrimination task that was previously learned ( Fritz et al. 2003 , 2005a , 2005b ). However, these neuroplastic changes were smaller or absent if the animal listened passively to the same sounds (i.e., when…

We found that this improvement results from a decrease in noise entropy that is associated with increasing correlations if the marginal distributions are unchanged. Surprisingly, for constant noise entropy and in the limit of large populations, the encoding accuracy is independent of both structure and magnitude of…

When correlations are increased, the noise power increases in a few low-frequency Fourier components while it decreases in all higher-frequency components (it quickly asymptotes to 1 − c 0 with increasing frequency; Fig. 1 D ). Because in homogeneous populations the stimulus encoding is confined to the low-frequency…

One potential caveat that has to be addressed when using Fisher information is that it provides only a bound (the Cramér–Rao bound) on the accuracy of a population code. Unfortunately, under some conditions potentially relevant for neural coding this bound is not tight, which means there exists no estimator that…

We set κ = 0.25 as determined from a dataset of 408 orientation tuning curves of neurons recorded in macaque primary visual cortex ( Ecker et al., 2010 ). We further assume that the noise correlation between two neurons depends only on their difference in preferred direction (limited range structure) and that…

Time cells are controlled by the temporal cues (the beginning and end of an episode) and the temporal structure (critical intervals) of an experience, just as place cells are controlled by the spatial cues (landmarks) and the spatial structure (shape) of the environment.

Importantly, the authors 18 observed that cells firing later in the delay period were active for longer durations (that is, they had larger ‘time-fields’) ( FIG. 1 ), a phenomenon that was also observed in other studies 19 , 20 (discussed below). This pattern suggests a scalar coding of time, which parallels a…

Perceptual performance was assessed using type 1 signal detection theory (SDT; Green and Swets, 1966 ). We calculated sensitivity

An influential model of metacognition postulates a dissociation between the “object” level cognition and the “meta” level, conceptualized as monitoring and controlling the object level

However, the same question arises here as in case of morphological details, i.e., which characteristics are relevant from a functional point of view, which are those that evolved as an adaptive property to enable the cell type to fulfil its job more efficiently, and which are those that exist simply as a side product…

Some neuronal classes show distinct peaks (" resonances ") in their impedance profiles at characteristic frequencies, which may contribute to their differential involvement in the generation of network oscillations in various frequency bands.

At the network level, both feed-forward and feed-back inhibition act to reduce the number of simultaneously active principal cells, working towards the creation of sparse representations (Acsády and Káli, 2007), which are thought to be advantageous for both sensory processing (Olshausen and Field, 2004) and long-term…

Considering the similar distribution pattern of VIP neurons through the cortical areas, and the broad projection of NDB to other cortical areas, we examined whether VIP neurons in other primary sensory cortices are also modulated by locomotion.

Interestingly, such retrograde tracing identified the nucleus of the diagonal band of Broca (NDB), a basal forebrain nucleus enriched in cholinergic neurons, as a prominent source of input to upper layer VIP neurons in V1

Because the jittered data sets preserve firing rates on timescales much broader than that of the jitter interval, the overall effect of the analysis is to identify as monosynaptic those pairs that showed excess co-firing at short latencies that cannot be accounted for by firing rates varying only at timescales of tens…

To more rigorously demonstrate position-dependent monosynaptic effects (the statistical issue is one of power; see Methods), we used a heuristic randomization argument based on thinning. For a given cell pair, we randomly and iteratively removed spikes occurring in maze segment(s) of interest until the remaining…

The sparse neuronal responses arising from a very low baseline to robust firing during a specific episode are reminiscent of the responses of hippocampal place cells in rodents ( 26 ), in which a cell responds whenever the animal is in a particular place in the environment.

The hippocampal and entorhinal machinery used in spatial navigation in rodents may have been preserved in humans but put to a more elaborate and abstract use

It has long been argued that the classification of neurons requires a multifaceted analysis of morphological and physiological features ( Tyner, 1975 ). More recent efforts have emphasized the importance of combining these features with molecular markers ( Ascoli et al., 2008 ; Tremblay et al., 2016 ; Zeng and Sanes…

In the cerebral cortex, a multifaceted classification scheme including molecular markers has enabled investigations into how specific classes of interneurons shape circuit computations, sensory processing, and animal behavior ( Cichon et al., 2017 ; Kato et al., 2017 ; Kato et al., 2015 ; Kuchibhotla et al., 2017…

To investigate the neurophysiology of WM capacity in birds, we adopted a task design developed for monkeys ( Buschman et al., 2011 ) to use it with carrion crows ( Corvus corone ).

We probed the WM capacity of crows using colored squares, based on the task design of Buschman et al., 2011 . Using the identical task allowed us to directly compare our neuronal results of WM capacity from NCL to results from PFC of monkeys. Task similarity is very important for such cross species comparisons as even…

Divisive normalization is a computational principle that acts upon neurons when presenting multiple stimuli simultaneously, it normalizes neuronal responses by creating ‘a ratio between the response of an individual neuron and the summed activity of a pool of neurons

We wanted to understand if DNR, the mechanism that we found reduced color information at load 2, could also produce color differentiation. The ‘normalization model of attention’ ( Reynolds and Heeger, 2009 ) incorporates divisive normalization, and can explain how attention can modulate neuronal responses. By…

Discrete models’ of WM argue that a fixed number of items can be stored. Once this capacity is reached, an additional item can only be maintained if it replaces a previous item ( Awh et al., 2007 ; Fukuda et al., 2010 ; Luck and Vogel, 1997 ; Vogel and Machizawa, 2004 ; Zhang and Luck, 2008 ). ‘Continuous models’…

The current study used a novel technique in humans that is capable of localizing transmembrane currents and multiunit activity not only to particular cortical areas, but also to different layers in those areas. Since feedforward and feedback information flow tends to involve different cortical layers ( Barbas and…

The local and distant ERPs and MEG produced by a cortical column can be directly estimated from its laminar CSD pattern. Specifically, in IT and PR, the initial sharp sink in layer IV combined with a source in layers II/III would be expected to produce a surface positive local field potential peaking shortly before…

Three patients with long-standing pharmaco-resistant complex partial seizures participated after fully informed consent according to NIH guidelines as monitored by the local Institutional Review Board. Participants were implanted with depth electrodes ( fig. 1 ) in order to localize their seizure focus and thus direct…

These issues have been partially addressed in macaques, where the latencies and durations of unit responses in ventral visual stream areas imply their sequential then simultaneous activation, and the delayed onset of distinctive unit responses to certain visual stimulus distinctions suggests that some processing may…

We used the behavioral model previously developed for this task 10 to obtain trial-by-trial, moment-by-moment estimates of the accumulating evidence, denoted by a(t) ( Extended Data Fig. 2 , Extended Data Table 1 ). Together with the simultaneously recorded firing rates r(t), this enabled the estimation of “tuning…

Due to the Poisson nature of the stimulus, given an underlying click-generating Poisson rate, the presence of a click at one moment in time has no bearing on the probability of a click at other times. Therefore, if one aligns the residual response to a click, it describes the change in response associated with that…

Laser illumination occurred on a random 25% of trials. Behavioral bias was measured as the mean difference between the observed “go ipsi” rate for inactivation and control trials for each of 10 binned stimulus strengths. Thus, a positive value represents an increase in ipsilateral responses on laser illumination…

We performed statistical comparisons of the quality of the fits using a nonparametric resampling bootstrap procedure. We first generated 200 sets of trials with the same trial count as the original data by resampling the original data with replacement. We then fit each of these sets with the models described above and…

Our results motivate consideration of a conceptual framework for decision-making and working memory in which sensory information used for the decision activates a neuronal sequence of activity. The sequence begins in a choice-independent state, which could be mediated by neurons that are not choice-specific (…

During working memory decision tasks the PPC may therefore perform computations through sequence-based circuit dynamics, rather than long-lived stable states, implemented using anatomically intermingled microcircuits.

We studied the encoding properties of neurons’ firing rates by quantifying the MI between the spiking of a neuron S and the movement condition C (in or out of response field) M I ( C , S ) = ∑ s , c P ( c ) P ( s | c ) l o g 2 ( P ( s | c ) P ( s ) ) . To derive the marginal and conditional probabilities of spiking…

In the beta-frequency band, the peak-to-trough modulation of spike counts was 13.6%, corresponding to a modulation in firing rate by about 6.6 spikes/s ( Fig. 3 B ). Spiking was distributed symmetrically about the spike-preferred beta-phase with no significant differences in the amount of spiking between the bins…

We found significant PAC between theta phases and beta amplitudes (permutation test, P < 10 −4 ) ( Fig. 4 A ). PAC for theta phases and gamma amplitudes (permutation test, P = 0.031) and beta phases and gamma amplitudes (permutation test, P < 10 −4 ) also was significant, albeit weaker (permutation tests, theta–beta…

We recorded neuronal activity while monkeys performed reward-guided look-and-reach decisions. At the start of each trial, in the baseline epoch, the monkeys maintained touch and fixation on a central target. Then, in the choice epoch, they were presented with two alternatives, a circle and a triangle, and had to…

The high-pass characteristic, however, can be predicted by time constants of SFA. If onset and steady-state response curves were approximated by linear functions, the cutoff frequency f hi for transmission of AM stimuli depended only on the time constant of SFA τ and can be predicted by f hi (τ) = (2πτ) −1

Propagated errors were calculated by partial differentiation for all four spike frequencies contributing to the interpolation equation.

However, unlike short-term memory models, in retrieved temporal context models, the contiguity effect is a result of a “jump back in time.” A repeated stimulus need not cause the same input as it did when it was first presented; a repeated stimulus can recover the state of context that was available before it was…

Episodic memory exhibits two extremely robust temporal effects in the laboratory: the recency effect and the contiguity effect. The recency effect describes the finding that more recently presented items are better remembered ( Murdock, 1962 ; Glenberg et al., 1980 ), while the contiguity effect refers to the finding…

Although our approaches revealed sites where neural activity was related to WM, it is likely that other mental processes contribute to the persistent changes in activity during the delay relative to baseline. In the spike activity, effects of other mental processes seem to be relatively small, because the spike rate…

Our report provides evidence for the sensory-recruitment hypothesis of WM ( Sreenivasan et al., 2014 ), which posits that storage of information recruits the same neurons in sensory cortex that represent the information. This hypothesis has mainly been based on multivariate analysis of fMRI signal patterns in early…

Working memory (WM) has been defined as a cognitive process for temporary storage of task-relevant information for goal-directed behaviors ( D’Esposito, 2007 ; Sreenivasan et al., 2014 ). The information can be related to past sensory events (e.g., short-term sensory memory), or to future sensory events (e.g., sensory…

In the auditory cortex of nonhuman primates, each of the three divisions of primary “core” cortex – A1, R and RT – exhibit tonotopic gradients that are mirror symmetric to each other

In contrast to the visual cortex, where retinotopic gradients reverse direction at the boundary between primary and secondary cortices, the receptive field gradients in auditory cortex run parallel to the primary/secondary (i.e., core/belt) boundary, such that the two mirror symmetric gradients observed in A1 and R…

we opted to use information theory measures because they provide a uniform scale that can be used to compare results from different experiments

From among the many statistical methods that could be applied (ANOVA, classification techniques such as linear discriminant analysis, etc.), we opted to use information theory measures because they provide a uniform scale that can be used to compare results from different experiments, their properties and biases have…

Artificial vowels were chosen as a more “naturalistic” class of stimuli than pure tones. Artificial vowels are a simplified version of vocalization sounds used by many species of mammals and have been used in studies of the ascending auditory pathway from the auditory nerve

For the training and for analysis of neuronal responses, it was crucial for the sounds to be easily distinguishable. For this reason, we ensured that the distance between formant peaks (0.585 octave) was well above the frequency difference at which rats reach plateau performance in tone discrimination

Only well-isolated single units that exhibited a clear refractory period were included in further analysis. In addition, we used two measures of spike separation, the L-ratio and the isolation index, to define the separation between the clusters in the multidimensional space

Smaller mammals, rodents in particular, provide several advantages over primates for physiological experiments: faster breeding times, lower costs, smaller housing needs, and currently, easier access to molecular and genetic tools.

We then fitted a logistic function to the psychometric performance and evaluated two parameters: the subjective category boundary and the slope of the curve.

In this context, which psychologists refer to as occasion setting ( Schmajuk and Holland, 1998 ), we suggest that the neural representation of motifs in CLM is less a sensory trace than a predictive mapping of the learned behavioral response.

In this context, which psychologists refer to as occasion setting ( Schmajuk and Holland, 1998 ), we suggest that the neural representation of motifs in CLM is less a sensory trace than a predictive mapping of the learned behavioral response.

Because motif identity is best regarded as a nominal, or categorical, variable (i.e. motifs cannot be easily described with a small number of parameters), we use multinomial logistic regression (MNLR) to find the optimal classifier that maximizes the predictability of motif identity from the firing rates of multiple…

To address this, we assessed the extent to which VIPs, compared to SOMs, are innervated by nearby PCs, by tracing presynaptic neurons of VIPs and SOMs with rabies (see Methods). Since similar experiments have been performed in V1

Since these data suggest that VIPs and SOMs do not share presynaptic partners, as a positive control we ran the same protocol on PVs. We chose PVs because they had the highest subthreshold cross-correlations in our data ( Figure S3C ), suggesting that they share many presynaptic partners

The situation is similar to motor coordination of agonist/antagonist muscle pairs where simultaneous contraction of both would not be energetically advantageous. Along this line of reasoning, it would make sense to segregate PC networks to feed only into one population of a mutually inhibitory pair of IN populations…

Co-activation of neurons inevitably depends on synaptic connectivity of excitatory as well as inhibitory neurons, but while co-activity of neocortical principal cells (PCs) has been studied extensively ( Ch’ng and Reid, 2010 , Miller et al., 2014 , Bathellier et al., 2012 , Sakata and Harris, 2009 ), that of…

VIP interneurons, themselves regulated by neuromodulators, may therefore enable selective patterns of activity to propagate through the cortex, by generating a “spotlight of attention

This type of local control could be use to dynamically sculpt selective cortical circuits out of a neural network type of connectivity matrix, and use them to implement specific perceptions, behaviors, memory states or, more generally, dynamical attractors.

We used adeno-associated virus (AAV) vectors to express the calcium indicator GCaMP6s ( Chen et al., 2013 ) in auditory cortex neurons of transgenic mice containing the activity independent reporter tdTomato in GABAergic neurons ( GAD2-IRES-Cre × Rosa-LSL-tdTomato ). This allowed us to optically distinguish…

Two to three weeks following virus injection and the implantation of a glass window over auditory cortex, we performed intrinsic signal imaging to map the precise position of A1. Responses to pure tones of three frequencies (3, 10 and 30 kHz) routinely revealed three cortical regions that displayed tonotopic…

To better estimate the time course of evoked activity, we calculated inferred spike rate from changes in fluorescence using deconvolution ( Vogelstein et al., 2010 ) and we used a single frequency based on the tone that activated the most cells during TRF mapping of each field.

Cortical photoinactivation shifted the psychometric curve to the right (n = 5 mice, Figures 5C and 5D ) indicating an increase in threshold (63% success rate) for sound detection (LED on : 51.9 ± 4.0 dB; LED off : 40.7 ± 2.6 dB; p = 0.03).

We thus used Shannon information [ I ( S ; R ); Eq. 1 ] to directly quantify the information carried by temporal spike patterns sampled at different temporal precision.

Shannon information measures the reduction of uncertainty about the stimulus gained by observing a single trial response (averaged over all stimuli and responses) and was computed from many (average 55) repeats of the same stimulus sequence by using the direct method

Our results reveal a dependency of neural response precision on the prominent stimulus time scales: The average PSTH-derived response precision ( Figs. 1 D and 2 D ) was finer, and the information loss with decreasing response precision ( Figs. 1 E and 2 E ) was larger, for the chord stimulus, which had a much shorter…

To address these questions, we fit the data to a linear dynamical system (LDS) model which predicted the activity of each cell based on two main components: (1) a weighted contribution of inputs from all other simultaneously recorded cells on the previous time step (the recurrent input), and (2) a contribution from a…

We quantified the selectivity of each cell as the selectivity index (SI) which was the difference between the mean response (0-1 s) to the vertical and angled grating divided by the pooled standard deviation.

To measure the overlap of labelling by transgenic mouse lines and immunostaining, we performed immunostaining on PV, SOM, and VIP transgenic mice (2 mice each) expressing tdTomato in the respective interneuron class, and determined the percentage of overlap between immunostaining and transgenic marker expression…

To test that the increased preference for task-relevant stimuli was not a result of nonlinearities in the relationship between a neuron’s firing rate and calcium concentration, we performed loose-patch recordings of spiking activity while simultaneously imaging GCaMP6 calcium fluorescence in from the three interneuron…

This MAP criterion results in the segregation of representational space into distinct regions separated by sharp decision boundaries (importantly, the placement of these boundaries does not constitute an additional hypothesis of the model, but derives directly from the hypothesis that decisions are based on a MAP…

Indeed, although SDT is not limited to a single dimension, it is often depicted as a binary problem with two Gaussian distributions plotted along a single axis. We argue that this classic diagram fails to capture the interaction between multiple features, classes and tasks, whereas a two-dimensional depiction fulfils…

Busemeyer et al. [ 69 ] have proposed accounting for the latter phenomenon with a computational principle inspired from quantum mechanics, according to which each successive judgement alters the input vector by projecting it onto a subspace defined by the task. As projections are not commutative, the order of…

According to Harnad's definition [ 53 ], categorical perception is defined by ‘within-category compression and between-category separation’. In a companion paper in preparation, we will present additional evidence that the conscious experience of our morphs follows Harnad's definition of categorical perception [ 53 ]…

The morphology of the pyramidal neurons was modelled based on cat visual cortex pyramidal neurons (Bush and Sejnowski 1993 ), and adjusted in accordance with anatomical findings in the human brain

Although the cortical column modelled in HNN was originally generated to account for the anatomy and behavior of primary somatosensory cortex (Jones et al. 2007 , 2009 ), it is based on canonical features shared between different neocortical circuits and hence can be applied to interpret signals in other cortical areas

Although the cortical column modelled in HNN was originally generated to account for the anatomy and behavior of primary somatosensory cortex (Jones et al. 2007 , 2009 ), it is based on canonical features shared between different neocortical circuits and hence can be applied to interpret signals in other cortical…

It is important to note that, since HNN is a large-scale model with thousands of differential equations and parameters, we cannot claim that any given waveform has a unique way in which to model it. With large numbers of parameters, many of which interact and trade off, HNN is primarily a hypothesis testing tool as it…

An early description of a fundamental anatomical circuit of sensory processing was based on cat visual cortex (Gilbert 1983 ; Gilbert and Wiesel 1989 ) and states that excitatory cells in layer IV of the neocortex receive thalamic inputs and project to superficial layers, which in turn project to deeper layers. This…

One explanation for contralateral dominance is that, while auditory processing is not as lateralized as, for example, somatosensory processing, those pathways between ear and cortex which cross over nevertheless appear dominant, with greater numbers of fibers and faster transmission speeds (Rosenzweig 1951 ; Kimura…

we evaluated changes in the propagation of high gamma activity using a recently developed technique – event related causality (ERC), based on the concept of Granger causality, to measure the timing, magnitude and directionality of task-related changes in neural propagation across cortical networks activated during…

In this model, the cortex is considered a form of hierarchical generative Bayesian statistical model.

In 1987, Muller and colleagues introduced the “random foraging” task, in which rats search continuously in all directions and locations to find food scattered throughout their environment ( Muller et al., 1987 ). Their aim was to “clamp” behavior (as foraging) and vary direction randomly to determine whether a spatial…

To simultaneously and quantitatively examine the extent to which each neuron was influenced by location, time, and distance, we fit the spiking of each neuron to a generalized linear model (GLM) that included treadmill time, treadmill distance, spatial position (x and y room coordinates), treadmill speed, and spike…

However, other neurons, and many of the same neurons that were active on the treadmill, had place fields elsewhere on the maze (see Movie S1 and Figure S3 ), indicating that during other components of the task, where locations on the maze were important to task success, space was a strong influence over firing…

During treadmill running, the rats’ heads were consistently facing forward, and 75% of the time spent on the treadmill could be accounted for by an area with a radius of approximately 3.3 cm (average area: 35 cm 2 ; standard deviation: 15.9 cm 2 ; range: 12 to 59 cm 2 ). This indicates that the location of the rats’…

Later, a patient with agnosia (D.F.), who has a large bilateral lesion of the occipitotemporal cortex and a small left-sided lesion of the occipitoparietal cortex ( FIG. 1b ) 4 , 5 , was found to have impaired perception of objects but intact ability to reach to objects, including shaping her grasping hand to reflect…

Strong correlations were also observed between time courses of fMRI responses in regions that constitute the parieto–medial temporal pathway — that is, the IPL, PCC and RSC — and the parahippocampal cortex ( FIG. 3 ; see REF. 53 for similar results in monkey and see REF. 54 for related results in human connectivity).

The purpose of feature selection is to reduce the set of features (in this case, voxels) in a dataset to those most likely to carry relevant information. This is effectively the same as removing voxels most likely to carry noise and is a way of increasing the signal-to-noise ratio.

However, without this being mentioned to subjects, there was in fact a third type of trials: one particular exemplar of repeated noise was presented over several trials, randomly interspersed throughout an experimental block. These trials (reference repeated noise, RefRN) were thus initially drawn from the same…

Using standard univariate (GLM) analysis, no difference in activity during the maintenance period was found for retention of a low versus a high tone. We used MVPA to test whether patterns of activity during the maintenance period could distinguish between low and high tones.

Behavioral studies ( Matsukura et al., 2007 ; Pertzov et al., 2013 ) show that, without any cue, items maintained in memory tend to be forgotten rapidly, but a selective retro-cue leads to protection of the cued item from temporal decay during the maintenance period. It is also known that maintaining multiple items…

Similarly, our proposed role of VIPs as the enablers of A1 plasticity after NIHL is consistent with previous reports showing that VIPs enable cortical plasticity across the sensory cortices 68 , 77 , 80 , 81 , 83 – 85 . In the visual cortex, synaptic transmission from VIPs to SOMs is necessary and sufficient for the…

The computational model assumes that after NIHL, the network must balance recovery and stabilization. The assumption that cortical inhibition is needed to prevent pathologic activity places the model in the inhibition-stabilized network (ISN) regime

panels. A more direct method for comparing terms across species is to plot the relative frequency of each term using Hinton plots, which were developed for visualizing weights of hidden units in neural networks ( Hinton and Shallice, 1991 ).

species-specific words (monkey, rat, mouse, etc.). The remaining text was then processed in R using the text-mining library (‘tm’) to create matrices of words

This approach revealed that anatomic terms were the most diverse, with 22 terms needed to account for all four species. By contrast, disease-related terms were least diverse, with just 12 terms needed to account for the ten most common terms across species.

We recently conducted a crowdsourcing effort to assess usage of anatomic terms for the rodent prefrontal cortex. We reached out directly via email to several leading human, monkey, and rodent PFC researchers and also requested via social media for anyone with an informed opinion on rodent PFC to fill out a survey on…

By measuring the curvature of the primate callosum and applying it to points in space representing the three main parts of the rodent medial PFC, we found that the three rodent areas rotate to the locations associated with the three major functional zones of the primate ACC: the subgenual region (sACC), the pregenual…

By measuring the curvature of the primate callosum and applying it to points in space representing the three main parts of the rodent medial PFC, we found that the three rodent areas rotate to the locations associated with the three major functional zones of the primate ACC: the subgenual region (sACC), the pregenual…

Any signal processing can only induce distortion ( Cover and Thomas, 1991 ). In particular, the propagation of spikes via synaptic transmission can only add noise in the form of lost spikes, added background activity, or spike time jitter, requiring a neuronal mechanism to minimize and compensate for added noise.

One approach is to analyze spike trains from the perspective of a downstream target. Here, we operationally defined temporal coding as a reliability profile that peaks at a timescale shorter than the maximal tested timescale, but in fact, we placed rate/temporal coding on a continuous scale. This approach, which does…

One approach is to analyze spike trains from the perspective of a downstream target. Here, we operationally defined temporal coding as a reliability profile that peaks at a timescale shorter than the maximal tested timescale, but in fact, we placed rate/temporal coding on a continuous scale. This approach, which does…

We found that neuronal response properties are qualitatively different when neurons are driven directly via photocurrents, compared with synaptic inputs. The direct optogenetic activation is largely somatic, whereas excitatory synaptic activation is largely mediated via synapses on the dendrites. Dendrites of PV cells…

The recent development of inhibitory-cell-type-specific transgenic mouse lines ( Taniguchi et al. 2011 ) opens a new window for in vivo identification of inhibitory neurons.

In auditory cortex, however, functional properties of genetically identified inhibitory neurons are poorly characterized. By two-photon imaging-guided recordings, we specifically targeted 2 major types of cortical inhibitory neuron, parvalbumin (PV) and somatostatin (SOM) expressing neurons, in superficial layers of…

Our intention was to insert the array 45° off the sagittal plane perpendicular to the IC surface and into the ICC to position the sites within different anatomical layers ( Geniec and Morest, 1971 ), which supposedly correspond to different frequency laminas based on animal studies

Briefly, 250 pps was high enough to avoid noticeable rate pitch effects (i.e., increasing rates up to 2400 pps did not noticeably increase the pitch from that at 250 pps) and the lowest rate available for daily stimulation to minimize adaptive effects. These parameters also achieved the largest drop in thresholds in…

For identification of the array location within different midbrain structures, 1 mm slices of the fused images were compared with fixed human brain slices of similar dimension that were taken from the anatomical brain collection at the Department of Neuroanatomy in Hannover Medical University ( Kretschmann and…

Each site was electrically stimulated with a 3-s-duration pulse train at C level, and the patient was asked to scale the perceived pitch based on our environmental scale (0–5) presented in Figure 5 . The patients were instructed to select an environmental sound on our pitch scale that most resembled the pitch level of…

In both species, however, the data suggest a hierarchy of contrast adaptation, wherein subcortical structures exhibit contrast gain control but in cortex this becomes more consistent across neurons (in ferrets) or more temporally stable (in ferrets and mice). In the visual system, a hierarchy of contrast normalization…

In the CNIC, time constants were very fast (median τ CNIC = 28 ms), indicating that substantial adaptation occurred during the first chord (duration 25 ms) after each spectro-temporal contrast transition (Fig. 6b ). For many CNIC units, the inclusion of an adaptation time constant did not improve predictions over the…

All participants showed this increase in sensitivity ( t (7) = 5.2, p = 0.003, n = 8), as measured by the just noticeable difference (JND, the dB difference between the 25% and 75% points on a fitted psychometric curve; Fig. 1c ). The JND increased by a mean of 38.8% between low- and high-contrast conditions (a…

The strength of perceptual contrast adaptation predicted by the model (mean predicted contrast adaptation: awake CNIC: 19.3%; anesthetized CNIC: 20.2%; MGBv: 17.9%; A1: 21.4%) closely resembled that measured in human participants performing the contrast-dependent sound level discrimination task (28.8%, n = 8…

The number of critical bands in the rat is not known, but a rough estimate can be based on two assumptions: (1) the basilar membranes of mammals are scale models of each other and critical bands cover equal distances on the basilar membrane ( Greenwood, 1990 ); and (2) one critical band is thought to cover ∼1 mm…

Furthermore, understanding this spectral coding will help to further develop promising new auditory prosthetic devices that use electrodes implanted in the IC and are now in clinical trials

In this way, each component reflects a linear combination of the power in each frequency band across all recording electrodes, such that the pairwise neural similarities between events are preserved.

Pattern of activations for a simulated 20-neuron neural network as a 15-item list is studied.

To reduce edge artifacts, we computed power at each frequency for the entire recording session before parsing the recordings into experimental events.

We presented our stimuli and analyzed our data with methods analogous to those used during behavioral detection experiments to best understand the neural responses that could underlie the perceptual phenomenon.

Our neurometric comparison used Noise-Alone-evoked firing and spontaneous firing as the backgrounds against which each threshold was determined to match perceptual measures. In psychophysical detection, listeners choose between alternatives of a masker with and without a tone, to yield a masked detection threshold. A…

Neurometric analysis requires the choosing of an appropriate encoding time window, defined as the window containing the response patterns contributing to the signal to be detected ( Panzeri et al. 2010 ). For these neurometric analyses, we employed two windows to test different aspects of masking. First, a brief…

A strength and limitation of the population neurometric used in the present study is that it pools information across all cells to make a decision for or against tone detection. In general, population coding assumes that all active neurons contribute to perception, whereas the lower envelope principle assumes that…

Mechanistically, forward masking is considered to involve a combination of synaptic depression, afterhyperpolarization, and inhibition ( Brosch and Schreiner 1997 ; Wehr and Zador 2005 ). A study of forward and backward masking in the bat inferior colliculus indicates that mechanisms involving the relative timing of…

We primarily focus on pupil diameter as a measure of state, owing to its ease of measurement, non-invasive nature, and ability to continuously and sensitively track state changes, whether or not they accompany overt walking, whisking, or other movements

The pupil diameter exhibited a strong inverse relationship to the rate of occurrence of fast ripples ( Figs. 1c–f , S1 ), with a peak coherence of 0.78 ± 0.07 (n=6 cells from N=6 animals) at low frequencies (<0.05 Hz) and a significant coherence at all frequencies up to 1 Hz ( Figs. 1e ). Theta activity was largely…

Plotting response latency on hit trials versus pupil diameter, for an example session, reveals that intermediate pupil diameters are associated with short latency licks and a large decrease in variability of lick latency. e, Group data demonstrating that lick latency on hit trials is shortest for intermediate pupil…

If the state changes reflected by pupil diameter had no effect, this relationship would be a diagonal line with slope of 1. Variations in pupil diameter exhibited a consistent change in the slope of this relationship, with the highest slope occurring at intermediate pupil diameters ( Fig. 5d–h ) for both ACtx and MG…

To reduce the excitatory effect of GtACR2, we screened a panel of somatodendritic targeting motifs to reduce the trafficking of GtACR2 to the axon and presynaptic terminals. We created a hybrid motif (Kv2.1C-linker-TlcnC) that is most effective in concentrating GtACR2 in the somatodendritic domain. Activation of…

Activation of GtACR2 with a short light pulse (0.5–10 ms) generated inward currents in all recorded GtACR2 – neurons that were voltage clamped at the reversal potential for GABAergic inhibition (−60 mV). The onsets of these inward currents followed the onset of the blue light by 3.19 ± 0.26 ms (mean ± s.e.m., n = 25)…

Therefore, it is also crucial to thoroughly characterize light-gated chloride channels, as their effect depends on the difference between the membrane potential and the reversal potential for chloride, both of which can vary in different neuronal types and subcellular compartments

The widely used light-driven inward chloride pumps and outward proton pumps, such as Natronomonas pharaonis halorhodopsin (NpHR) and Halorubrum sodomense archaerhodopsin (Arch), can hyperpolarize membrane potentials, independent of the electrochemical gradients, to inhibit action potentials with millisecond precision…

A linear SVM computes a simple thresholded weighted sum of inputs, an operation that is plausibly implementable by actual biological neurons; high linear classifier performance has been suggested as an indicator that the neural representation is such that it can be easily readout by downstream neurons 62 .

Apart from one neuron (onset 120 ms after the texture stop tone) the others displayed onset times well before the translation stage came to rest (onset 580 ± 65 ms before texture stop tone, n = 18 neurons). This indicates that the Catch-trial responses were not due to the stop auditory tone and could potentially…

As a complement to the ideal observer ROC analysis, we trained a linear support vector machine (SVM) classifier to decode texture graininess and texture omission from single-trial population activity, on a frame by frame basis. This simple readout model could effectively decode texture graininess and texture omission…

place cell remapping was more pronounced in rats that primarily learned to fear the training environment (context group) compared with rats that primarily learned to fear the auditory CS (cued group), even though the stimuli (CS, US, and training box) in both tasks were the same

If it is true that place cell remapping allows the hippocampus to represent different states of a single environment, then the hippocampus must solve an intriguing stability-plasticity problem ( Grossberg, 1988 ), namely, place cells must somehow decide when the state of a given environment is stable versus when it…

To further quantify the remapping of place cells caused by fear acquisition, we calculated two correlation indices for each place cell—one for the training ( r T ) and one for the control box ( r C )—by computing the pixel-by-pixel correlation between preconditioning and postconditioning place maps (see Materials and…

If this principle generalizes across sensory modalities, PV+ neurons in mouse auditory cortex should be well tuned for frequency, because it has tonotopically organized frequency columns.

Monotonicity index (MI) characterizes the strength of a cell's intensity tuning. We defined MI as the neuron's response at maximum intensity (90 dB) divided by its maximum response ( Sutter and Schreiner, 1995 ; de la Rocha et al., 2008 ; Watkins and Barbour, 2011 ). An MI of 1 indicates no intensity tuning; an MI…

This model is based on the distribution of AN innervation in the CN with respect to cochlear origin, and makes no assumptions about nor imposes directionality to frequency organization throughout the volume of the nucleus.

With the mouse ear, spectral notches are largely observed in the >20 kHz range ( Lauer et al., 2011 ), which is where our vertical cell counts are the lowest. Furthermore, the transfer function of the mouse ear shows overall gains in the 10 – 20 kHz range ( Lauer et al., 2011 ), where our cell counts are higher.

To distinguish PFC-dependent behaviors which require intact PVI signaling from those that do not, we compared PVI-selective interference with non-cell-type-selective perturbations of the same circuitry in behavioral assays that were chosen to detect alterations that map onto symptom categories (positive, negative…

As Cre-recombinase is required to flip the reading frame into the correct orientation, transcription of TeLC can only occur in PVIs 26 . Once expressed, TeLC efficiently stops transmitter release by cleaving VAMP2, a protein required for synaptic vesicle docking

It is thought that both positive symptoms and increased amphetamine sensitivity are due to enhanced subcortical dopaminergic tone, which in turn correlates with and might be secondary to PFC dysfunction in schizophrenia

A class of models called attractor networks can perform these functions through strong recurrent synaptic interactions ( Wang, 2008 ). In the attractor network framework, strong synaptic connections among neurons can provide reverberatory excitation, potentially mediated by slow NMDA receptors ( Wang, 1999 ), that…

An important feature of our distributed circuit model is the pathway-specific E/I balance in the feedforward projection from selection to action cells. This E/I balance regulates a cascade of activations across functional cell types and can be characterized as discrete flow, since response preparation in action cells…

Whereas SSA has also been found in sub-cortical structures e.g. in the auditory midbrain ( Malmierca et al., 2009 ; Zhao et al., 2011 ; Thomas et al., 2012 ) and the auditory thalamus ( Kraus et al., 1994 ; Anderson et al., 2009 ; Antunes et al., 2010 ; Bauerle et al., 2011 ), it is weak in the lemniscal areas of the…

As a proof-of-principle that would account for our findings that PVs and SOMs exhibit similar magnitude of SSA, yet have a differential effect on SSA in putative excitatory neurons, we constructed a simplified model of mutually coupled inhibitory–excitatory neuronal populations

Human studies have shown that the left superior temporal gyrus (STG) is more capable of integrating information over a shorter timescale and plays a greater role in speech perception and phonological processing than the right [ 1 – 3 ]. On the other hand, the right STG has longer integration windows to potentially…

The DG model is a spiking generative model that can capture correlation structures in spiking neural data [ 46 ]. Sample (binarized) spike trains X ( t ) were generated by thresholding samples of a latent multivariate Gaussian time series V ( t ) X ( t ) = 1 iff V ( t ) > 0 with V ∼ N ( γ , Σ ) with Σ ( t , t ) = 1…

In the first-order approximation of a system, the causal link between recurrent anatomy and time constant is based on the fact that excitatory feedback increases the time constant, therefore it provides an approximation of the dynamics by measuring how quickly the correlation in the neural activity decays over time…

Mouse vocalizations are composed of syllables (i.e., a sound unit separated from other sound units by silence [ 36 ]), which themselves contain 1 or several pitch trajectories. The duration of individual pitch trajectories within a syllable emitted by adult male mice can range from 30 to 90 ms [ 37 , 38 ]. This range…

This revealed that in the perirhinal cortex some neurons are suppressed by any picture repetition, regardless of relevance, whereas others are enhanced, but only when a picture matches the sample

We used a statistical learning approach [ 34 ] to quantify whether the information from IFPs available in single trials was sufficient to distinguish whether it is memory maintenance (match task) or simulation of a specific future event (switch task).

Like the Gaussian beam model, the SAG model is a solution of the paraxial Helmholtz equation.

The raised sine AM sound contains more spectral sidebands than SAM ( Bernstein et al., 2009 ) as does any sound with a rapid rise time.

CP is the index of the alignment: A CP of 0 indicates that the ITD curves are aligned near their peaks, while a CP of 0.5 indicates that the ITD curves are aligned near their troughs

A Bernoulli Naive Bayes classifier ( McCallum and Nigam, 1998 ) is used to read out the spike trains from individual neurons to categorize the sound shape.

The distance metric was normalized by trial variances to compute a sensitivity index or discrimination index as commonly used to measure behavioral discriminability

Functional hierarchies in the visual cortices support the concept that classification of visual objects requires successive cortical stages of processing including a progressive increase in classical receptive field size. The present study is significant as it supports the idea that a similar progression exists in…

The exponential time constant, τ, determines the temporal resolution or integration time of the distance metric. For large values of τ, the signals being compared contain mostly slow fluctuations in the spike rate ( Fig. 3 E , F ). For small τ, the spike distance metric is sensitive to the precise timing of spikes. We…

Here, a D′ = 1 corresponds ∼70% accuracy, which is typically considered a critical limit for discriminating a signal behaviorally ( von Trapp et al., 2016 ).

By design, the naive Bayes classifier treats responses bins from different neurons as if they are independent. This property allows the classifier to take advantage of any independent and nonredundant responses within the population to build more robust classification.

Since the majority of FS interneurons are PV+ ( Kawaguchi and Kondo 2002 ) and G42 mice express the EGFP transgene in (PV+) cells, we compared the properties of GFP+ interneurons recorded from G42 mice with FS cells recorded in SW mice of the same age. We found that the intrinsic membrane properties and AP properties…

At rest, the short duration EPSPs are consistent with predominantly AMPA receptor–mediated current and correlated with FS cell membrane time constants throughout development.

Synaptic depression has also been implicated in the barrel cortex, where suppression has been observed during whisking (“engaged”) compared with quiet wakefulness (“passive”), consistent with the present findings

Synaptic depression of the thalamocortical inputs 15 , 35 could explain how the relative enhancement of the thalamic spontaneous rate in the engaged condition might lead to suppression of the cortical evoked response, without changing the cortical spontaneous activity.

To best conceptualize these inherent lifecourse dynamics, we have documented the distribution of 7 different markers of GABAergic inhibitory interneurons on healthy Long-Evans rats from 9 days (P9) at five time point during the rats' life until advanced maturity at 25 months (P750, equivalent to ~75 human years based…

With this evidence, we show how understanding these trajectories of cell counts may be factored into a simple model to quantify changes in inhibitory signaling across the course of life, which may be applied as a framework for creating more advanced simulations of interneuronal implication in normal cerebral…

To relate neural and perceptual representations of the auditory frequencies, we compared the cortical DM calculated for each ROI to the group perceptual DM. We computed the Spearman correlation between the perceptual DM and each participant’s cortical DMs. A high correlation in these analyses would indicate that the…

Admittedly, our approach can be substantially improved in future studies. For instance, we compared the cortical dissimilarity measures to the perceptual dissimilarity judgments tested offline and averaged over subjects. We took this approach because the task performed during the discrimination scans, which was…

The co-occurrence of auditory and somatosensory signals that are highly specific in the frequency domain may build audio-tactile associations in frequency-processing circuits through an extensive history of co-activation. In this framework, the auditory responses in parietal cortex could reflect predictive coding…

In non-human primates, neurons in primary somatosensory cortex can signal vibration frequencies above 100 Hz in their spike timing ( Harvey et al. 2013 ), but evidence for explicit frequency tuning in somatosensory cortex remains elusive. Whether auditory information is similarly carried in somatosensory cortex using…

Finally, we received further confirmation that our results stem from a developing relationship between successive time segments rather than from changes in the statistics of the firing rates by separately calculating the two components of the MI: the marginal entropy and the conditional entropy ( 31 ) Marginal entropy…

Moreover, most animal studies use paradigms in which learning takes many trials, and the animals typically are overtrained, but human memory can form following a single experience ( 1 – 4 ). Here, the neuronal changes already were seen during the second viewing, namely after only one viewing, as happens in real life…

the integration of scores across the various indicators of consciousness can be used as a graded criterion for consciousness, in a similar vein as when unresponsive, brain-damaged patients are subjected to various neurological tests and their scores are summed up to determine the overall grade on the Glasgow Coma…

Again, this approach follows the logic of abductive reasoning, which compares hypotheses and infers the better model based on simplicity, effectiveness and the available evidence (Josephson and Josephson, 1996 ).

The integration of scores on the various indicators yields an overall, graded criterion for consciousness, somewhat comparable to the Glasgow Coma Scale for unresponsive patients.

As with all phenomena throughout nature, a particular phenomenon X (e.g., magnetism or frozenness) can only be claimed to occur in a system if the system exhibits manifest properties indicating that X is occurring in that system. For instance, iron but not plastic can be said to have magnetic properties because it…

While it has not been uncommon in the past to associate consciousness with volition and voluntary decision-making (Crick and Koch, 2003 ), these latter two concepts have been difficult to test or quantify in practice, whereas goal-directed behavior (see below) is a well-defined concept that has been operationalized in…

The rationale is that the evidence for consciousness will optimally accumulate across the study of multiple behaviors (taxing goal-directed behavior, episodic memory, etc.), which should be maintained under varying environmental circumstances (e.g., with novelty, detours) under which stereotypical, pre-programmed…

Using the bifurcation diagram derived for fixed connectivity, we study analytically the temporal evolution and the steady state of the learned recurrent architecture as a function of parameters characterizing the external inputs. Slow changing stimuli lead to PA, while fast changing stimuli lead to SA. Our network…

As explained in Zenke and Gerstner ( 2017 ) and Zenke et al. ( 2017 ), in order to prevent the runaway of the synaptic weights produced by Hebbian plasticity, the timescale of any compensatory mechanism should be of the same order or faster than the Hebbian timescale. For generalized homeostatic plasticity, the…

The models investigated can be roughly divided in two categories: models with supervised and unsupervised plasticity rules. In models with supervised plasticity rules, the synapses are updated according the activity of the network and an error signal that carries information about the difference between the current…

We use a rate model to describe the activity of populations of neurons (Wilson and Cowan, 1972 ). The connectivity in this model represents the average of the synaptic connections between populations of neurons, allowing to investigate at a mesoscopic level the learning mechanisms of PA and SA. This model has the…

Interestingly, some PPC cells encoded the stimulus in a contrast-dependent manner, but also encoded the choice in a contrast-independent manner (Supplementary Fig. 5c ). We quantified the contrast-dependence of the selectivity index for each neuron by measuring its slope as a function of contrast (Supplementary Fig…

Linear models that consider the stimulus, task context, and licking together can explain some of the variance in calcium responses. But could even simpler models be sufficient? For each cell, we trained three additional partial models: a stimulus-only model, a motor-only model, and a stimulus + engagement model that…

V1 neurons were strongly stimulus-selective, with the majority (74.3% ± 5.2% of cells, Fig. 8a , top) of neurons lying within the first and third quadrants (Fig. 7g ). By contrast, the majority (66.8% ± 13.0% of cells, Fig. 8a , bottom) of PPC neurons were found in the fourth quadrant, indicating a preference for the…

A unique mode of inhibitory control may be provided by inhibitory neurons that specifically suppress the firing of other inhibitory neurons. Such disinhibition could lead to the selective amplification of local processing and serve the important computational functions of gating and gain modulation

This model resulted in only marginal improvement relative to the divisive model for the inhibited group (Bayesian information criterion 34 for the combined, divisive gain and baseline shift models: −399.6, −398.3 and −354.7) and the baseline shift model for the delayed activated group (Bayesian information criterion…

However, we presented theoretical arguments in favor of limited information. First, if cortical populations have extensive information then the brain would need to throw away almost all of it to explain behavioral performance. Second, since cortical populations are much larger than the sensory population but not much…

In contrast, the prediction of suboptimal decoding ( Eq. 2 ) was poorly matched to data across all areas ( Figure 7C , middle panel). The best linear combination of predictors using the regression weights above could provide a better explanation than either predictor alone, but the improvement over the parameter-free…

However, one drawback with the inattention paradigm is that it only includes 3 of the possible 4 combinations of visual awareness and task-relevance; i.e., the unaware, task-relevant condition, which is common in other awareness paradigms, is absent in the inattentional blindness paradigm. This missing condition, in…

To illustrate the problem of conflating neural correlates of post-perceptual processing with correlates of conscious perception, it is useful to consider “the refrigerator door problem” (a neural counterpart to the “refrigerator light illusion” described by Block, 2001 ). Imagine you have no access to the internal…

Because the behavioral experiment revealed detection rates greater than zero for the 16.67 ms color stimuli in some subjects, an additional behavioral post-test was conducted after each EEG session. In this post-test, color stimuli (4-red-lines), shape stimuli (squares), and control stimuli (random arrays) were…

Cluster mass permutation tests for each condition revealed a different pattern of effects from that of the shape-elicited P3b. In this case, color-elicited P3b amplitudes were significant for all conditions except the unaware, task-irrelevant condition. The P3b in the unaware, task-relevant condition (1.31 μV, SD =…

It typically takes longer to train NHPs to learn an auditory discrimination or memory task than to learn a similar task using visual stimuli ( D'Amato and Salmon 1984 ; Fritz et al., 2005 ; Hashiya and Kojima 2001 ).

For example, if a Campbell's monkey makes an alarm call for an eagle, Diana monkeys will also produce alarm calls signaling eagles, however, if a boom vocalization occurs before the alarm call of the Campbell monkey the Diana monkeys ignores the warning ( Zuberbuhler 2002 ). The boom vocalization changes the meaning…

For example, Lomber & Malhotra (2008) dissociated the function of auditory cortical regions when they showed that inactivation of the anterior auditory field, AAF, in cats impaired auditory pattern discrimination, while lesions of area DP, a hypothesized dorsal stream region, impaired sound localization ( Lomber and…

Due to the capacitance and resistance of the neural cell membrane, the membrane potential and hence the firing rate is approximately a low-pass filtered version of the synaptic current. A common simple dynamic model of neurons that captures this phenomenon is the differential equation ( Eq 7 ) known as the firing-rate…

To overcome overfitting, the weights were regularized using an L1-norm (LASSO regularization).

The models receive the input as a cochleagram, a spectrogram-like transformation of the sound waveform. The cochleagram approximates the spectral filtering performed by the auditory periphery

We then used a standard machine learning technique, the linear Support Vector Machine (SVM) 30 , to train one classifier for choice and a second for modality.

Neurons in monkey inferotemporal cortex (IT) are likewise tolerant: many neurons have a preferred stimulus identity that is stable, though modulated, across many retinal positions 29 . Indeed, our task configuration is reminiscent of that used to study object recognition – just as a given object can be viewed from two…

We used a novel test, PAIRS, to demonstrate that task parameters and time-varying response features are distributed randomly across neurons. This configuration does not pose a problem for decoding: a linear SVM could accurately estimate the modality of the stimulus and the rat’s choice based on single-trial responses…

An alternative hypothesis is that neurons reflect random combinations of parameters, leading to neural populations in which neurons’ responses defy categorization. Theoretical work suggests a major advantage for category free populations: when parameters are distributed randomly across neurons, an arbitrary group of…

We used these nearest-neighbor angles to compute a statistic indicating whether the population had an excess of small nearest-neighbor angles. We term this statistic “PAIRS”: Projection Angle Index of Response Similarity (Online Methods).

Recent models propose four subsystems of working memory, a “central executive,” responsible for controlling and coordinating information through “slave” systems called the visual-spatial sketchpad for manipulation of visual objects, the phonological loop for verbal rehearsal, and the latest addition, an episodic…

Reverberatory networks, when left unperturbed, will settle into an attractor state defined by a stereotyped pattern of activity within the network ( Hopfield, 1982 ). Attractor models may undergo spontaneous oscillations, although network instantiations have also been shown to be capable of mediating sustained…

Perhaps the signature effect of PPC damage is the neglect syndrome, typically occurring after a lesion in the right hemisphere. Disturbances include the inability to detect an object in the contralateral (left) visual hemifield (egocentric neglect) or to perceive the left side of objects, regardless of where they…

We use these cylinders to probe the variation of response difference (Figure 3 E) or centroid frequency (Figure 4 E) with depth in the tissue, a hemodynamic analog to making electrode penetrations into the tissue.

The success of these surface-based analysis methods will enable more detailed non-invasive explorations of the functional architecture of other subcortical human auditory structures that have complex, laminar organization.

Thus, the notion of using tissue depth as a reference frame was proven to work fairly well, despite the patchy character of the data.

In addition, concept cells share many features with place cells in the rodent hippocampus (Quian Quiroga, 2012a ). Place cells increase their firing rate when the animal crosses a specific location in an environment (O’keefe & Nadel, 1978 ). They are selective, firing strongly to a particular place field, and they…

The screening data used in the study of Pedreira and colleagues had only six presentations of the stimuli. Although a response modulation with stimulus repetition was evident, the stability of these representations over several trials could not be addressed, as it was hard to see a steady state in the response…

Motivated by recent theoretical advances in understanding how machine learning principles play out in the functioning of neuronal circuits

This analysis revealed that the observed mixed selectivity can be naturally understood as a signature of the information encoding strategy of state-of-the-art classifiers like support vector machines

just as it allows them to implement arbitrary binary classifications by modifying the weights of a readout neuron (using, for instance, a supervised procedure like the perceptron learning rule [ 23 ]).

Moreover, mixed selectivity offers a significant computational advantage over specialized responses in terms of the repertoire of input-output functions implementable by readout neurons. This advantage originates from the highly diverse non-linear selectivity to mixtures of task-relevant variables, a signature of…

Our method relies on the observation that the number of binary classifications that can be implemented by a linear classifier grows exponentially with the number of dimensions of the neural representations of the patterns of activities to be classified ( Supplementary Methods M.1 ). Hence dimensionality can be…

A theoretical argument ( Supplementary Section S.18 ) shows that neurons with a strong non-linear mixed selectivity are more sensitive than pure selectivity neurons to the task irrelevant sources of variability. Non-linear mixed selectivity is most useful but also most fragile.

This was computed by creating activation likelihood estimation (ALE) maps for each of the clusters, which compared the ALE scores to a null‐distribution reflecting random spatial associations between experiments with a fixed within‐experiment distribution of foci, yielding a P ‐value based on the proportion of equal…

BrainMap archives functional neuroimaging studies by coding statistically significant results, in the form of stereotactic coordinates, with associated meta‐data such as behavioral domain, paradigm class, and subject population

K ‐means clustering is a non‐hierarchical clustering method that uses an iterative algorithm to separate the voxels in the ROI into k non‐overlapping clusters [Forgy, 1965 ; Hartigan and Wong, 1979 ], by minimizing the variance within clusters and maximizing the variance between clusters. To do this, the algorithm…

Furthermore, they speculated that the ventral (anterior in humans) portion was more engaged in limbic processes (i.e., “hot” processing), and the dorsal (posterior in humans) was preferentially activated during tasks such as spatial navigation, or learned associations (i.e., “cold” processes).

To solve this problem, we designed a novel method, the “masked EM algorithm” 30 . This algorithm fits the data as a mixture of Gaussians, but with each feature vector replaced by a virtual ensemble in which features with masks near zero are replaced by a noise distribution (see Methods). Channels with low mask values…

Specifically, spikes are detected as spatiotemporally connected components, in which the filtered signal exceeds a “weak threshold” θ w for every point, and in which at least one point exceeds a “strong threshold”

We separately assessed consistency on spikes that all operators had identified be in “good” clusters, on spikes that at least one operator had identified to be in a good cluster, and on all remaining spikes. Similarity was assessed with the Fowlkes-Mallows index 31 , which gives a score between 1 for complete…

A similar situation arises in many fields of data-intensive science: in electron microscopic connectomics, for example, automatic methods can only be used under the supervision of human operators

There are no antibodies to the 5HT3a receptor available, precluding the use of IHC to determine the size of the 5HT3aR-expressing interneuron population and estimate its contribution to the total interneuron family. The availability of a GFP mouse line that reliably reports the presence of 5HT3a receptors allowed us…

Another feature arguing for a true delineation between SOM+/CR− and SOM+/CR+ Martinotti cells is evidence suggesting that they are derived from different areas during development, with the SOM+/CR+ population mainly arising from the dorsal Nkx6-2-positive region of the MGE

MMN is quantified by arithmetically subtracting ERPs to the standard tone from ERPs to the deviant tone.

This would be analogous to a MMN-P3a sequence in humans that is only observable in full (i.e., also including P3a) when deviant tones of high magnitude attract involuntary switches of attention [1] , [4] .

These non-independent processes for the coding of time in the working brain support Henri Bergson’s theory about the perception of time (Bergson, 1889).

Observed acalculia was thus classified in three main categories ( Berger, 1926 ; Hécaen et al., 1961 ; Hécaen and Angelergues, 1961 ): (1) “primary acalculia” (“anarithmethia”), the disturbance of core math functions, resulting from lesions of the left parietal areas; (2) secondary acalculia, determined by language…

Unlike for the IPS, the right PSPL is not considered to be specific to quantity-based processing, but to mechanisms of visuo-spatial attention, which might be progressively engaged or “recycled” in these tasks during arithmetic education

Intracellular studies have revealed the importance of cotuned excitatory and inhibitory inputs to neurons in auditory cortex, but typical spectrotemporal receptive field models of neuronal processing cannot account for this overlapping tuning. Here, we apply a new nonlinear modeling framework to extracellular data…

We recorded the responses of isolated A1 neurons to segments of continuous speech. Speech samples were taken from the Texas Instruments/Massachusetts Institute of Technology (TIMIT) database ( Garofolo 1988 ). Stimuli were sentences (3–4 s) sampled each from a different speaker and balanced across sex. The digital…

as the standard first-order description of the stimulus selectivity of an auditory neuron, the linear spectrotemporal receptive field (STRF) offers an intuition for how the neuron responds to complex stimuli. Sounds that most closely match the STRF (in both frequency and relative timing) will drive the strongest…

Two main approaches have been taken to model nonlinear aspects of A1 neuron responses. One approach has been to identify additional stimulus features (in addition to the linear STRF) that contribute to the computation underlying the neuronal response, for example using spike-triggered covariance (STC; Sen et al. 2000…

Notably, whereas the gain of stimulus-evoked responses in visual cortical pyramidal cells increases with locomotion 5 , 25 , perhaps to compensate for increased visual flow, auditory cortical responses to tones decreased during movement. This suppressive effect, which resembles corollary discharge signals described in…

Whereas acoustic stimulation activates the auditory system from the periphery to the cortex, this optogenetic approach allowed us to effectively bypass the ascending auditory pathway prior to the thalamocortical projection and to thus isolate the component of motor-related suppression that occurs within the auditory…

One common, conceptually straightforward framework models the effects of synaptic inhibition as a linear transformation with a divisive (scaling) and a subtractive (shifting) component ( Chance and Abbott, 2000 ; Doiron et al., 2001 ; Mitchell and Silver, 2003 ; Prescott and De Koninck, 2003 ; Hao et al., 2009 ). In…

A simple network model shows that threshold nonlinearities can interact with network activity to transform subtractive inhibition of neurons into divisive inhibition of networks, or vice versa. Varying threshold and the strength of suppression of a model neuron could determine whether the effect of inhibition appeared…

Because of genetic tools, mice are increasingly used for neuroscience experiments that were traditionally performed using rats. However, mice are smaller and “less intelligent” than rats, limiting the size of neural implants and the complexity of performed behaviors. Here, we show that these problems are exacerbated…

Because of genetic tools, mice are increasingly used for neuroscience experiments that were traditionally performed using rats. However, mice are smaller and “less intelligent” than rats, limiting the size of neural implants and the complexity of performed behaviors. Here, we show that these problems are exacerbated…

The hybrid vigor and the enhanced behavioral capabilities may yield more trials in every experimental session, shorter learning periods, and higher accuracy in complex tasks. By increasing yield and accuracy, the usage of HYB may allow uncovering unexplored neuronal mechanisms. Enhanced behavior also has ethical…

During an action potential, the recorded waveforms depend on neuronal morphology, spike initiation site, and the relative position of the electrodes and the subcellular compartments 3 – 7 . Extracellular potentials recorded next to different compartments are expected to exhibit distinct polarities 8 – 10 . However…

Taken together, the experimental findings and computational models support three hypotheses for the source of non-negative extracellular potentials during action potentials: axonal forward propagation, dendritic backpropagation, and return currents. Thus, the compartmental origin of non-negative extracellular…

Positive phases of non-negative spikes occur in synchrony or just before wider same-unit negative spikes. Narrow positive spikes occur in isolation in the white matter. Isolated biphasic spikes are narrower than negative spikes, occurring right after spikes of verified inhibitory units. In CA1, units with dominant…

The analysis of P- and B-spikes may have direct implications for studying neural diseases. Presently, measurements of axonal propagation velocity are carried out ex vivo 49 , 64 , 87 – 89 or under anesthesia 90 . Future studies may measure axonal propagation velocity in the intact brain directly by computing time lags…

Although the identity of the basket cell has not been questioned, the many other cell types described by Ramon y Cajal (1893) and Lorente de No (1934) have either been ignored and all non-pyramidal cells called basket cells, or non-pyramidal cells were named by the laminar location of their soma, or some other simple…

With the cited evidence we hope to convince our readers that some frequently used criteria about the identity of interneurones are unsustainable. (i) Somatic location in a layer does not identify an interneurone class, as the same class may have somata in several layers and all layers contain several distinct classes…

Most of the GABAergic cell types defined in the CA1 area have homologues in the isocortex, which is particularly apparent in the supragranular layers. For example, the somata of supragranular pyramidal cells are innervated by basket cells immunopositive for PV, or CCK, or CCK and VGLUT3 ( Kawaguchi & Kubota, 1997…

Probably all neurones of the cortex can be defined, recognized and compared on the comprehensive application of the following measures: (i) brain area- and cell domain-specific distribution of input and output synapses, (ii) expression of proteins involved in cell signalling, (iii) intrinsic membrane properties…

The primate dorsolateral prefrontal cortex is functionally analogous to, but anatomically distinct from, the rodent prelimbic region of the mPFC

Given the inhomogeneous and distributed nature of the representation of spatial information among recorded mPFC units, a maximum margin linear classifier 22 was used to decode sample goal location from binned population firing rate vectors and to quantify the strength and reliability of the neural representation

The last expression has the conceptual benefit of opening the loop, effectively describing a feedback system (Fig. 2a ) as a feedforward system using an arithmetic decomposition (Fig. 2e ). Moreover, understanding that the CCH is a sum of three elements allows reconstructing hidden elements, namely the STCs, from the…

Thus, a CCH can be described as a sum of three elements: (1) the convolution between the ACH of neuron 1 and the impulse response from neuron 1 to neuron 2; (2) the convolution between the ACH of neuron 2 and the impulse response from neuron 2 to neuron 1; and (3) the cross-correlation between the background spike…

For a uniform planar (Lambertian) light source of area A s and a straight (cleaved) optical fiber of cross-sectional area A f having a numerical aperture NA in , the maximum coupling efficiency is ( Hudson 1974 )

Two factors, which have opposing practical implications, were ignored in the foregoing: 1 ) reflective losses; and 2 ) skew rays. Since there are inevitable differences between the RIs of the source, coupling medium, and fiber core, there is attenuation due to reflection at each interface. This is quantified by the…

The mean (± SE) scattering coefficients depended on wavelength and were ( Fig. 3 A , bottom left ): blue light, 7.18 ± 0.17; orange, 4.37 ± 0.15; and red, 3.44 ± 0.05. For blue light, the current value is smaller than previously reported values (10.3 for the rat brain; Aravanis et al. 2007 ). The mismatch could be…

The volume of the illuminated brain tissue [at an intensity of >1 mW/mm 2 , the documented threshold for stimulating channelrhodopsin2 (ChR2); Aravanis et al. 2007 ; Boyden et al. 2005 ] was ∼0.001 mm 3 , formed by a truncated cone with 180-μm height and 150-μm base diameter ( Figs. 1 B and 3 ). Red laser diodes…

Because the diode-probe arrays require only electrical connections, they can be used wirelessly ( Wentz et al. 2011 ), enabling recording and stimulation experiments with, for instance, freely moving birds and/or long-term naturalistic experiments with larger animals while permitting precise, large-scale…

To demonstrate physiological closed-loop control in a freely moving animal, we used the activity of a well-isolated neuron recorded on one shank of a diode probe implanted in the CA1 pyramidal layer to trigger optical stimulation on multiple other shanks ( Fig. 7 A ). Comparison of the cross-correlation histograms…

Testing of these models has been hampered by the correlative nature of most in vivo studies. On the other hand, interpretation of in vitro studies is constrained because many applied drugs are not selective for specific neuron types and can affect both SPW and ripple generation mechanisms, thus limiting separation…

In support of a critical role of pyramidal neurons, local PYR silencing terminated the ripple events. Ripple-contingent illumination in CaMKII::Arch mice for 20–50 ms resulted in localized suppression of PYR spiking and ripple power

To increase the power of detecting second order relations between spike trains, we agglomerated the spikes of all PYR recorded on the same shank (median, 6 PYR; range, 1–33) into “summed PYR” activity and all INT spikes into “summed INT” (median, 2 INT; range, 1–9) and quantified the coherence between the resulting…

To this end, we rank ordered the spikes of all pyramidal cells and interneurons that occurred in a given event ( Fig. 4 A ), and determined the consistency of multineuronal spiking across events ( Fig. 4 B ); because induced ripples were focal (one site was illuminated at a time; Fig. 2 Ac ), this analysis was done on…

We tested the “local-circuit” hypothesis by comparing the probability of participation and sequential firing of CA1 neurons during theta oscillations, natural spontaneous ripple events, and “synthetic” ripples induced by local optogenetic activation of pyramidal neurons.

Choice signals emerged with similar timing across choice-encoding regions ( Figure 4c-d ). To examine timing, we performed two analyses. First, we trained a decoder to predict the subject’s choice from recorded population activity, after first subtracting the prediction of population activity from the Vision and…

To further confirm these conclusions, we developed a version of choice probability analysis for tasks with many stimulus conditions, called “combined-conditions choice probability” ( Methods ). This statistic quantifies the probability that a neuron’s spike count will be greater on trials with one choice than trials…

We divided the recorded neurons into two spatially segregated sets, and divided the recorded timepoints into two equal halves (training and test; Fig. 1I ). The training timepoints were used to find the dimensions in each cell set’s activity that maximally covary with each other. These dimensions are termed Shared…

We extracted a 1,000-dimensional summary of the motor actions visible on the mouse’s face by applying principal component analysis to the spatial distribution of facial motion at each moment in time ( 36 ).

This multidimensional behavior measure predicted approximately twice as much variance as the three arousal variables ( Fig. 2D-J , Movie S3 ).

The invariant responses to individual persons and landmarks observed in the human MTL may be compared to the striking place fields in rodents, which appear to encode particular locations in the animal’s environment

Since the pioneering observations of Wilder Penfield, focal electrical stimulation of MTL circuits has been shown to evoke old memories or the feeling of déjà

Moreover, quantitative maps provide predictive tools to determine the optimal stimulus for a particular neuron based on its location in the tissue. Using this information investigators can 1) relate anatomical, biophysical, and pharmacological characteristics of a neuron to sensory processing based on stimulus…

We refer to the stimulus type with a modulation rate in theta band range (4–7 Hz) as a theta (θ) sound, the stimulus type with modulation rate in the alpha band range (8–12 Hz) as an alpha ( α ) sound, and the stimulus type with modulation rate in the gamma band range (30–45 Hz) as a gamma (γ) sound.

The results of the mutual information analyses demonstrate that phase patterns in the theta and gamma bands track the temporal structure of the stimuli, as quantified by the cochlear-scaled correlation. The robust phase coherence observed in the theta band for θ sounds and that in the gamma band for γ sounds is indeed…

To quantify the acoustic edges and extract the temporal structure of the stimuli, inspired by the concept of cochlear-scaled entropy [ 112 ], we created an index, cochlear-scaled correlation. We first used a Gammatone filterbank of 64 banks, ranging from 50 Hz to 22,050 Hz, to decompose the sounds and extracted the…

This design, however, builds in a hole in processing, a segregation of function between low and high processing rates—perhaps optimized for sensory sampling—by an intermediate rate, perhaps optimized for allocating attentional and memory resources and functionally inhibiting task- or stimulus-irrelevant actions…

To reveal potential interactions of caffeine and UMTS MP exposure in RT and oscillatory measures we focused on the exposure block and we used the additive analysis model with the following formula, as applied elsewhere 42 , 43 , 44 : Hereafter, “[Caffeine − Control] + [UMTS − Control]” and “Combined − Control” are…

Saliva samples were taken at the beginning and the end of each recording session and caffeine concentrations were determined by high-performance liquid chromatography (HPLC).

Consistent with this idea, the hippocampal network contains long range projecting SST cells that are present by P5 and particularly effective in supporting immature network synchronization ( Bonifazi et al., 2009 ; Picardo et al., 2011 ). These ‘hub’ SST interneurons in the hippocampus precociously exhibit mature…

Because after P10 rabies glycoprotein levels from the Rosa-locus are insufficient to mediate synaptic transfer, we modified our approach to examine later developmental time points. Post-P10, the conditional Rosa-TVA reporter line ( Seidler et al., 2008 ) was used to target RV-mCh infection into SST interneurons…

Previous work by Sanes and colleagues has shown that LTS-SST interneurons in the L4 of gerbil auditory cortex display a developmental decrease in thalamic evoked synaptic potentials, in contrast to the developmental increase in thalamic synaptic potentials evoked in FS-PV interneurons ( Takesian et al., 2013 ). Here…

Given that developmental insults to interneurons (PV interneurons in particular) are implicated as the underlying etiology of psychiatric disease ( Karayannis et al., 2014 ; Marin, 2012 ; Owen et al., 2013 ), our results likely have particular importance. Specifically, they reveal the unanticipated development…

We chose artificial vowels as a more “naturalistic” class of stimuli than pure tones.

One virtually infallible method of enhancing memory is simply to relate the to-be-remembered information to one's self.

In animals, selective sparse coding has also been observed in recordings from the MTL ( 15 , 16 ).

Furthermore, famous faces and names have long been used to query the integrity of recent and remote semantic memory in patients with temporal lobe epilepsy (TLE) ( 3 , 6 – 11 ).

Theoretically, predictive coding suggests that the brain is constantly making efforts to ‘fit’ internal models in perceiving through inferring the incoming sensory input. The discrepancies between the actual sensory data and the predicted sensory data (‘error’) are used to refine the model in an iterative process…

We propose that, there is scale-free topology in the cortical network, which contains hub neurons in L2/3 and many low-degree loops with different lengths in L5 (Fig. 5 ; modified from the previous study 5 ). These low-degree loops enable the neural system to follow the external input rhythm, while hub neurons can…

Such a multiplicative mechanism is exactly what is needed to translate the allocentric entorhinal representation into goal-directed movements.

The dorsal stream, which provides the PPC with its visual input, has been described as being critical for spatial perception, enabling the representation of the locations of objects in space

Active Inference, a corollary of the free energy principle (FEP), is a first principles approach to modelling (approximately) Bayes optimal behaviour (Friston; 2010; Friston et al, 2016, 2017a).

Interestingly, our data are also compatible with two earlier two-photon calcium imaging studies ( Ito et al., 2014 ; Barnstedt et al., 2015 ). Ito et al. (2014) reported gradients in the medial regions of the dorsal IC, which ran from lateral (low-frequency) to medial (high-frequency), whereas Barnstedt et al. (2015)…

The visual signal appears to serve as a teaching signal for auditory modality, resulting in self-supervised learning of sensory representations.

However, an important difference between motor adaptation and the current example of sensory adaptation is that in the former, direct feedback can be used as teaching signal. Moreover, the motor system is expected to be highly malleable and dynamic (for instance, due to muscle fatigue), and thus, subject to adjustment.

The monolithically integrated μLED probes described in this work are expected to bridge the gap between the technological advances in semiconductors and advanced applications in systems neuroscience.

Heat transfer physics in the brain with consideration of the μLED heat source and dissipation due to blood perfusion is governed by Penne’s equation

We report a scalable method to monolithically integrate microscopic light emitting diodes (μLEDs) and recording sites onto silicon neural probes for optogenetic applications in neuroscience. Each μLED and recording site has dimensions similar to a pyramidal neuron soma, providing confined emission and…

While LEDs are available at much lower cost and in various wavelengths as compared to laser diodes, the coupling efficiency between an integrated waveguide to the Lambertian emission profile of LEDs is severely limited by the principle of etendue

To build a conservative model, we assumed that all electrical input power is converted into heat. In addition, we only analyzed the temperature increase caused by the most distal μLED (LED1 in Figure S2A ). As illustrated in Figure S2B , the thermal energy generated at the μLED is most effectively dissipated through…

Lemniscal neurons are tonotopically organized ( Aitkin and Webster, 1972 ; Webster et al., 1992 ; Winer and Schreiner, 2011 ), narrowly tuned to a specific single frequency, and respond to repetitive tonal stimuli with fidelity. However, non-lemniscal neurons are not tonotopically organized, but are broadly frequency…

The MS was inactivated by an injection of muscimol (an agonist of GABA A receptors). Its effect lasts more than 1 h ( Martin and Ghez, 1999 ), and the half-life time of its effect is longer than that of lidocaine ( Martin and Ghez, 1999 ). Therefore, the inactivation of the MS with muscimol lasts long enough for the…

Auditory fear conditioning includes trace fear conditioning and delay fear conditioning. Fear conditioning is an associative learning task in which subjects are presented with a neutral CS (such as a tone) paired with an aversive US (footshock). The subject quickly learns that the CS predicts the US. As the predictive…

Since the A1 latency was longer and the MS latency was shorter than the CA3 and CA1 latencies, it is most likely that auditory information sent to the hippocampus comes from the non-lemniscal pathway, not the lemniscal one.

Regular spiking and bursting firing types were originally described for cortical pyramidal neurons (Connors et al., 1982 ), and it is important to note that the firing properties of RS or bursting SOM cells are analogous but not identical to those classically observed in pyramidal neurons.

These rebound spikes/bursts are mediated by T-type calcium channels, similar to those found in thalamic relay neurons (Goldberg et al., 2004 ; Ma et al., 2006 ). Like relay neurons, L5 LTS cells can fire in either tonic or bursting mode, depending on their membrane potential.

The results of that study highlight the importance of examining the separate processes underlying perception, using methods such as ROC analysis, rather than simply treating perception as a unitary phenomenon.

Further support for the notion that the hippocampus is involved in supporting high-resolution binding comes from a recent study conducted by WeiWei Zhang (in preparation; Society for Neuroscience Abstracts), in which we made use of a color wheel task developed by Zhang and Luck (2008) . On each trial, individuals were…

Whether the spike latency tuning is simply relayed along sensory ascending pathways or generated by local circuits remains unclear. Here, in vivo whole-cell recordings from rat auditory cortical neurons in layer 4 revealed that the onset latency of their aggregate thalamic input exhibited nearly flat tuning for sound…

Due to the use of QX-314 in the intrapipette solution to improve the recording quality, we were unable to examine the bona fide spike responses of the same neuron. Nonetheless, we derived the expected spike latency by using an integrate-and-fire neuron model, feeding the model with experimentally observed excitatory…

We next examined whether the latency tuning of thalamic inputs was necessary for the generation of cortical spike latency tuning. As shown in Figure 7 D , although outputs of individual thalamic neurons exhibited a clear latency tuning, the aggregate input to each pyramidal neuron had a flat latency tuning. This…

Several sources of internal time reference have been proposed, including large-scale oscillations ( Hopfield, 1995 ), local field potentials ( Eggermont, 1998 ), and population onsets ( Stecker and Middlebrooks, 2003 ; Chase and Young, 2007 ). In our modeling study, we found that for any given tone stimulus, a large…

Specifically, the mismatch negativity (MMN) is a neurophysiological difference waveform peaking in the 150–250 ms window after stimulus onset. The MMN refers to the difference in evoked response to the standard and deviant stimulus. Importantly, the MMN is distinct from the N100 (occurring between 50 and 150 ms post…

A third block’s (many-standards control block) stimuli consisted of 10 equiprobable drifting gratings of different motion directions (same structure and stimuli as the initial tuning curve session); stimuli presented in this third condition served as controls that do not elicit adaptation effects of the standard…

ROIs that exhibited stimulus-evoked activity (300–1,500 ms) 1.5 standard deviations above baseline (− 200 to 0 ms) mean activity for at least 400 consecutive milliseconds for at least 25% of trials, and 1.5 standard deviations above baseline mean activity for at least 400 consecutive milliseconds in the trial average…

Our results may provide insight to the mechanisms underlying the dysfunction of oddball-related sensory processing deficits in psychiatric disorders. One prominent mechanistic theory in schizophrenia research revolves around the role of N-methyl D-aspartate receptor (NMDAr)-dependent parvalbumin positive (PV+)…

The insular and temporal areas along the lateral aspect of the cortex formed two distinct clusters and the broad and unique intracortical connections of the claustrum and lateral entorhinal area suggest they may serve as hubs, or regions of high network interaction ( Sporns, 2010 ).

The clustering orders nodes into modules that maximize the connectivity and arrange highly interconnected nodes such that they are clustered along the matrix diagonal, facilitating visualization of grouped regions that can be considered subnetworks.

We trained rats to discriminate low and high frequency “cloud-of-tones” stimuli in a two alternative choice task

These observations indicate that neurones in the striatum preserve the information available to perform the ”cloud-of-tones” task.

In the first strategy, we targeted ChR2 specifically to corticostriatal neurones using a Herpes Simplex Virus-1 (HSV1) engineered to express Cre recombinase 19 , 20 , 21 ( Fig. 2a ). This virus, when injected into the auditory striatum, was transported retrogradely along the axons and drove Cre expression in…

Our results suggest that the aversive thirst motivational state sets a landscape of “initial conditions,” spread across many brain regions, that determine subsequent sensory stimuli–evoked brainwide neural dynamics.

Our results comport with the low dimensionality and pervasiveness of brainwide cellular activity during behavior in both Caenorhabditis elegans ( 39 ) and larval zebrafish

This choice is motivated by dynamical systems and control theoretical arguments indicating that negative feedback loops from fast to slow subsystems constitute dynamical building blocks for fast and stable responses to inputs

Regularized Least-Square Classification is a machine learning technique that estimates the linear separability between patterns according to their class.

The present study explores the possibility that appropriate descending input can also be used to improve the function of the injured spinal cord.

Furthermore, human data suggest that the thousands of trials per day obtained from rats are not essential and that conditioning can be achieved with three to five sessions per week of several hundred trials each

For example, women tend to outperform men on tasks that involve verbal or semantic rules and memories related to personal experience, whereas men perform better on tasks that require the manipulation of complex spatial information, such as the manipulation of shapes in space

For example, alcoholism, autism and attention deficit hyperactivity disorder (ADHD) are much more common in men, whereas Alzheimer's disease, social phobias, eating disorders, post-traumatic stress disorder (PTSD) and major depression are more common in women

Here we scaled calcium imaging, combining standard operating procedures with integrated engineering tools to address some of the challenges of this difficult technique, to create an unprecedented survey of 59,610 neurons in mouse visual cortex, across 243 mice, using a standard and well-studied but diverse set of…

We therefore extracted the fMRI signal profile from the left and right motor cortices, and used it to derive an index of lateralized motor activation analogous to the LRP, the lateralized bold response (LBR; Fig. 5).

The transition to the ignited state can be described, in theoretical physics terms, as a stochastic phase transition – a sudden change in neuronal dynamics whose occurrence depends in part on stimulus characteristics and in part on spontaneous fluctuations in activity (Dehaene and Changeux, 2005; Dehaene et al…

However, capitalizing on the earlier concept of a blackboard 22 system in artificial intelligence (a common data structure shared and updated by many specialized modules), Baars (1989) proposed an homunculus-free psychological model where the current conscious content is represented within a distinct mental space…

PCI estimates both the information content and the integration of brain activations through the computation of the normalized Lempel-Ziv complexity (Lempel & Ziv 1976) of the significant EEG spatiotemporal responses to TMS.

syntax is not inherent in the words employed or in the idea to be expressed

In a manner analogous to the use of behavioral measures in priming experiments, the MR adaptation technique seeks to draw inferences about the response properties of single neurons from the degree of stimulus invariance of BOLD signal adaptation (Grill-Spector et al. 1999; Kourtzi and Kanwisher 2001; Vuilleumier et…

analysis at the computational level has drawn on ideas from reinforcement

Furthermore, several features of DA cell activity match properties of the prediction error signal of the temporal difference (TD) algorithm for machine learning, leading to the hypothesis that DA cell activity may be providing a teaching signal within a neural analog of a TD learning system in the brain

In the temporal difference algorithm, an estimate of the expected reward at a particular time step t is derived from the difference between the prediction of all future rewards at that time step, P ( t ), and the prediction of all future rewards that was generated at the previous time step, P ( t - 1) ( Sutton, 1988…

The concept that for delayed associative conditioning to occur there must be some memory or trace of the antecedent signal at the time of a subsequent reward is as old as the study of classical conditioning itself

A low learning rate may be considered a disadvantage. However, previous studies in machine learning have found that when λ is set high to enable learning to begin early in training, low values of α improve the stability of learning

the amount of compensation is predicted by a Bayesian model for location inference that uses eye-centered storage. information and for changes in CTU when the target INTRODUCTION When humans reach out and grasp an object, information about the object’s location arrives at different times through multiple sensory…

Both genome and connectome constitute complex networks

The compilation of the genome was aided by the fact that base pairs and genes are relatively straightforward choices as basic structural elements.

In principle, part of the frequency preference of individual cells could result from slow adaptation (due to e.g., ChR2 dynamics, cellular adaptation, and/or calcium buildup). To examine this possibility we tested a subset of units with both ascending (0–40 Hz) and descending (40-0 Hz) chirps

Theta band-limited discharge of PYR upon PV neuron activation can occur for at least two reasons. First, at high frequencies the high density of spikes emitted by PV cells can tonically suppress their targets, whereas at lower frequencies PYR can still fire in longer windows devoid of strong PV activity, creating in…

Because the top-down mechanism was originally proposed for the impact of higher-order visual cortical areas to lower-order cortical areas, the focus has been primarily on the intracortical feedback pathway.

The auditory system faces a similar task in that it must differentiate spectral changes in a sound introduced by the animal’s own movements from spectral changes introduced by the movement of an external sound source relative to the animal.

In this way, anti-Hebbian STDP adjusts parallel fiber synaptic weights in order to sculpt a “negative image” of the neural response caused by the fish’s own movements.

The RHT postulates that the performance of a perceptual task is first based on the highest available level of sensory representation. If the task cannot be accomplished at that level (because of poor sensory resolution), it proceeds down the representational hierarchy to obtain more detailed, lower-level cues that…

Cerebellum-like structures act as adaptive sensory processors in which the signals conveyed by parallel fibers in the molecular layer predict the patterns of sensory input to the deep layers through a process of associative anti-Hebbian synaptic plasticity

For the TAM study, vaginal cytology was obtained through daily vaginal smears (12:00 to 14:00).

Based on its antiestrogenic properties, TAM has been used as a tool to evaluate the role of estrogen in sexually dimorphic behaviors such as anxiety ( 47 ), agonistic behavior (e.g., ref. 48 ), and sexual receptivity (e.g., ref. 49 ).

The simulations also revealed another limitation of the raw scores: closely related cell types tend to have correlating scores (Additional file 2: Figure S5). That is, scores may show enrichment for a cell type due to a “spillover effect” between closely related cell types. This problem mimics the spillover problem in…

In five of the cell types the scores from the random mixtures consistently produced 0; thus, we define those distributions as constant 0.001 (Additional file 2: Figure S7).

as a distributed representation for words, has been recently established in natural language processing (NLP)

The basic idea behind training such vectors is that the meaning of a word is characterized by its context, i.e. neighboring words.

Interesting patterns have been observed by training word vectors using Skip-gram in natural language.

Distributed representation was originally inspired by the structure of human memory, where the items are stored in a “content-addressable” fashion.

Hub species in networks are often hypothesized to serve as keystone species, a concept which has been transferred from macro-ecology into microbiome research [ 82 ].

Definitions based on ecology describe the microbiome following the concepts derived from the ecology of multicellular organisms.

The frequency-based score statistic is best thought of as a transformation that takes as input two values—the ratio of the sum-of-squared residuals, and the number of observations—and outputs a score that is a better classification statistic than the ratio of the sum-of-squared residuals alone.

Let total sample DNA (T) be a mixture of two components (T = C + S): contaminating DNA (C) present in uniform concentration across samples and true sample DNA (S) present in varying concentration across samples.

To prepare, panellists developed a discussion outline and target questions. Several delivered brief presentations that addressed background and core issues. Discussion ensued for each issue until consensus was achieved. After the meeting, individual panellists wrote sections of the summary, which were compiled by…

We therefore considered the possibility of constraining the model parameters through regularization, by combining information across similar genes to increase robustness and reduce sampling variation. This approach is commonly applied in learning error models for bulk RNA-seq in the context of differential expression…

We utilize the Pearson residuals (response residuals divided by the expected standard deviation), effectively representing a variance-stabilizing transformation (VST), where both lowly and highly expressed genes are transformed onto a common scale.

has benefited from recent advances in understanding the generic properties of complex networks

Animal studies which use dietary fiber supplementation to manipulate colonic SCFA tend to use relatively high fiber supplementation; 5 – 20% w/w NDC in animal dry matter intake (DMI).

Nowadays, species taxonomy is confronted with the challenge to fully incorporate new theory, methods and data from disciplines that study the origin, limits and evolution of species.

Considering the characteristics of gut microbiota such as the large diversity, the stability and resilience, and the symbiotic interaction with the host, we can define the host and the microorganisms inhabiting it as a “superorganism” \ [8, 9\] which performs immune and metabolic functions

Doing so, we repeat and reflect on the assumptions in previous back-of-the-envelope calculations, also known as Fermi problems. We find such estimates as effective sanity checks and a way to improve our quantitative understanding in biology.

It is prudent in making such estimates to approach the analysis from different angles. In that spirit, we now ask does the cumulative mass of the cells counted fall within the expected range for a reference adult?

large-scale machine learning systems, and a computing infrastructure that can support flexible and dynamic queries

For RNA-seq and other ‘omics applications, genomics will benefit greatly from the lessons learned in particle physics, in which in most cases raw data are discarded almost as fast as they are generated in favor of higher level and greatly compressed summaries.

In 1948 Shannon asked whether we could attach a number to the amount of information we gain

Similar observations were made in pigs, where SLC16A1 mRNA levels increased in cecal and colonic mucosa after dietary supplementation with RS compared to digestible starch (DS) ( 41). In contrast, SLC5A8 mRNA levels (encoding SMCT1) were not affected by RS or DS diet ( 41), showing a specific regulation of MCT1…

Here, we aim to provide an overview of microbial SCFAs production in the intestine and their effect on intestinal cells and the immune response. Moreover, gut microbiome changes in IBD are reviewed and how they are related to impaired intestinal SCFAs production and associate to cell metabolism and signaling pathways…

Finally, the microbiome configuration and immune responses are both increasingly appreciated to be highly variable among human individuals, with more variances typically explained by inter-individual variation than by disease state.

In addition, many studies focusing on microbiome-immunity interaction have utilized 16S rRNA sequencing to characterize the microbiome, but this modality is limited by its genus-level and purely compositional resolution. Given that strain level resolution and functional insights are better served by shotgun…

We propose a framework for augmenting the standard mathematician’s toolkit with powerful pattern recognition and interpretation methods from machine learning and demonstrate its value and generality by showing how it led us to two fundamental new discoveries, one in topology and another in representation theory.

In this work we use gradient-based techniques 40 , broadly similar to sensitivity analysis in classical statistics and sometimes referred to as saliency maps.

Our contribution shows how mature machine learning methodologies can be adapted and integrated into existing mathematical workflows to achieve novel results.

We propose a framework for augmenting the standard mathematician’s toolkit with powerful pattern recognition and interpretation methods from machine learning and demonstrate its value and generality by showing how it led us to two fundamental new discoveries, one in topology and another in representation theory.

DL, a subset of ML (Fig. 2), is inspired by the information processing patterns found in the human brain. DL does not require any human-designed rules to operate; rather, it uses a large amount of data to map the given input to specific labels.

Nevertheless, although TL enhances the accuracy of several tasks in the fields of pattern recognition and computer vision, there is an essential issue related to the source data type used by the TL as compared to the target dataset. For instance, enhancing the medical image classification performance of CNN models is…

In contrast, the method outlined in this work uses relative position vectors rather than simply distances (scalars) together with features comprised of not only scalars, but also higher-order geometric tensors. This makes internal features instead equivariant to rotation and allows for angular information to be used…

The exponent of this power-law (or equivalently the slope in log-log space) determines how fast a learning algorithm learns as new data become available. Empirical results have shown that this exponent typically remains fixed across different learning algorithms for a given data set, and different methods only shift…

To test GPT-3 on another task that is somewhat unusual relative to the typical distribution of text, we collected a set of 374 “SAT analogy” problems [TLBS03].

BERT alleviates the previously mentioned unidirectionality constraint by using a “masked language model” (MLM) pre-training objective, inspired by the Cloze task (Taylor, 1953).

Their approach is inspired by _matching_, a concept from graph theory where one tries to find a subset of edges in a graph such that the edges do not share any vertices.

This framework corresponds to a minimax two-player game

fitting an approximate inference model

The model is a convolutional neural network, trained with a variant of Q-learning, whose input is raw pixels and whose output is a value function estimating future rewards.

Apart from deep GMDH networks (Sec. 5.3), the Neocognitron (Fukushima, 1979, 1980, 2013a) was perhaps the first artificial NN that deserved the attribute deep, and the first to incorporate the neurophysiological insights of Sec. 5.2.

A motivation for dropout comes from a theory of the role of sex in evolution

I shall replace the question by another, which is closely related to it and is expressed in relatively unambiguous words

For 173 countries with available data, we calculated annual plastic emissions entering aquatic ecosystems using a distance-based probability function. This function estimates the proportion of inadequately managed waste to reach the nearest aquatic ecosystem based on spatially explicit waste generation and downhill…

This requires plastic waste generation to be reduced by 40% in HI, 35% in UMI and LMI, and 25% in LI countries compared with the BAU trajectory. Levels of managed waste must reach 99% in HI and UMI countries, 80% in LMI countries, and 60% in LI countries. Recovery of 40% of annual global emissions by 2030 is needed

For PFOS, PFOA, and PFNA, however—unlike lipophilic POPs whose serum concentrations increase with age —concentrations were quite similar among the four age groups (Tables 2–5), a finding that agrees with previous data.

This process becomes more important as plastic particles become smaller since at decreasing particle size the surface area∶volume relationship is increased dramatically and oxidation levels are higher, enhancing their biodegradation potential.

However, there are specific uses that make an immediate ban of all PFAS impractical. Some specific uses of PFAS may currently be essential to health, safety or the functioning of today’s society for which alternatives so far do not exist. On the other hand, if some uses of PFAS are found to be non-essential, they…

Per- and polyfluoroalkyl substances (PFAS) are of concern because of their very high persistence and impacts on human and environmental health. Currently, many different PFAS (on the order of several thousands) are used in a wide range of applications and there is no comprehensive source of information on the many…

Recently, Hermsen et al. proposed a weight-of-evidence scoring method for studies of microplastic ingestion by marine biota ( Hermsen et al., 2018). This method defined minimum quality criteria for various aspects of the analytical procedure, such as sampling, sample treatment, use of controls and polymer…

Nonetheless, it is important to notice that comparisons between river discharge predictions from GLDAS and observations in 66 basins worldwide demonstrated that predictions are somewhat dryer than observations. The authors of this validation study attributed the differences to uncertainties in precipitation rates.

Not all studies considered here reported micro- and macro-plastic concentrations at surface waters of rivers. As such, for our midpoint estimate, we homogenized our data set using the mean ratio micro- to macro-plastic numerical concentration from studies reporting both types (mean ratio equals to 0.04). For…

As buoyant plastics can be missed by surface trawls due to wind-driven mixing, we then estimated the ‘depth-integrated’ mass and numerical plastic concentrations (Ci) for all type/size categories at each of the trawl sampling locations using the equations described in ref.. Supplementary Methods 1 provides details on…

The dependence of the particle trajectory on the windage coefficient predicted by our model is in good agreement with sightings and modelling of debris originated from the 2011 Tohoku tsunami in Japan. The first identified Japanese debris items that arrived after 10 to 12 months on the North American shores were…

One approach to quantifying plastic particles in the nascent field of plastic particle HRA is based on mass concentrations of polymers from plastic present as particles, analogous to PM10 for instance. ### 1.3.

We used WinNonlin software, version 4.1 (Pharsight Corporation, Mountain View, CA) to calculate the half-life of elimination based on the mean value of the split analyses. The data were linear when plotted as the logarithm of serum concentration versus time. Therefore, we assumed a first order model.

The diversity of proximal tubular organic anion transporters and potential for genetic variation have indicated that the long elimination half-life in humans compared with that in other species may be due to differential expression of organic anion transporters and could be linked to either low-level transport into…

In addition, a number of oceanographic processes could aid in the transfer of microplastics to depth. These processes include dense shelf water cascading, severe coastal storms, offshore convection and saline subduction. All these induce vertical and horizontal transfers of large volumes of particle loaded waters…

Some negatively buoyant particles will sink; however, because of surface tension and oceanographic currents, most plastics are initially held at the sea surface. Colonization by organisms, adherence to phytoplankton and the aggregation with organic debris and small particles in the form of marine snow will eventually…

We rely on Bower and Forgas’s (2001) theory of emotional priming to argue that specific emotions from IRAs play an important role in activating racial attitudes.

As in priming studies in which humans were asked to name partially occluded images that they either had or had not seen previously ( Mitchell, 2006 ; Snodgrass & Feenan, 1990 ), we required monkeys to classify partially occluded photographs that they either had or had not seen previously.

Critically, by importing one of the strictest indicators of genuine nonconscious processing in human studies

Much work in human cognitive science has shown that under certain circumstances, people display opposite behavioral signatures when they are consciously aware of stimuli (i.e., when they are exposed to clearly visible stimuli—supraliminal stimuli) versus when they are not aware (i.e., when they are exposed to stimuli…

First, an extensive literature review was conducted to assess all general scales on fear. Thirty measures on fear were identified that assess fear on different populations and diseases (available on request from the corresponding authors). Relevant and possible items were pooled by two researchers (i.e., the third and…

Four criteria must be met to justify a reverse inference that a particular facial configuration expresses and therefore reveals a specific emotional state: reliability, specificity, generalizability and validity (explained in Table 2 and Figure 3). These criteria are commonly encountered in the field of psychological…

When you see someone smile and infer that the person is happy, you are making what is known as a reverse inference: you are assuming that the smile reveals something about the person’s emotional state that you cannot access directly (see Figure 3).

This paper presents a critique of expected utility theory as a descriptive model of decision making under risk, and develops an alternative model, called prospect theory.

Consistent with the public health approach and the adaption of a disease model to understand gambling, a clear theme of the contagion of harm from the individual to family and friends, and then community emerged, noting that the person who gambles is the index case and not the source.

This is an important broadening of focus that assists in addressing gambling related harm from a public health perspective.

the results are analyzed in terms of the concepts of information theory

Since these experiments would not have been done without the appearance of information theory on the psychological scene, and since the results are analyzed in terms of the concepts of information theory, I shall have to preface my discussion with a few remarks about this theory.

The "amount of information" is exactly the same concept that we have talked about for years under the name of "variance."

Accordingly, recent work in our lab has begun to apply cascade models of language production (e.g., Dell, 1986 ; Morsella & Miozzo, 2002 ; Navarette & Costa, 2004 ) to these next-generation questions concerning social behavior production ( Morsella, Levine, & Bargh, 2005 ).

It is suggested that models of complex conceptual structures ( Lakoff & Johnson, 1980 ), language use in real-life conversational settings ( Clark, 1996 ), and speech production ( Dell, 1986 ) might hold the key for solving these two important ‘second-generation’ research problems.

The notion of priming originated in Karl Lashley’s (1951) analysis of language comprehension; how we need to hold some sentential information temporarily in mind in order to comprehend it.

Although the idea of priming per se originated within classic cognitive psychology and psycholinguistics, its nature and the set of related ideas changed when they were applied to phenomena that interested social psychologists.

Models of nested levels of influence in the study of race relations 17 , human development 18 and culture 19 , 20 can be used to consider the relation between racial bias and broader systemic factors (Fig. 1 ).

Furthermore, we model the spread of information with epidemic models, characterizing for each platform its basic reproduction number ( R0 ), i.e. the average number of secondary cases (users that start posting about COVID-19) an “infectious” individual (an individual already posting on COVID-19) will create. In…

We tag links as reliable or questionable according to the data reported by the independent fact-checking organization Media Bias/Fact Check34. In order to clarify the limits of an approach that is based on labelling news outlets rather than single articles, as for instance performed in33,48, we report the definitions…

The general knowledge task consisted of a questionnaire with 42 difficult multiple-choice questions borrowed from the game Trivial Pursuit (1984/1987).

This research suggests that people may be drawn to conspiracy theories when—compared with nonconspiracy explanations—they promise to satisfy important social psychological motives that can be characterized as epistemic (e.g., the desire for understanding, accuracy, and subjective certainty), existential (e.g., the…

In general, empirically warranted (vs. speculative), parsimonious (vs. complex), and falsifiable explanations are stronger according to normative standards of causal explanation (e.g., in science; see). However, conspiracy theories appear to provide broad, internally consistent explanations that allow people to…

For decades, economists have had the last (and often the only) word on money, and yet some of the biggest worldwide events of recent history stem from a failure to understand the psychology of money.

Prior to deciding which headlines they would share on social media, participants were subtly primed to think about accuracy by being asked to rate the accuracy of a single non-COVID-related news headline. This minimal, content-neutral intervention nearly tripled participants’ level of discernment between sharing true…

Such interventions are easily scalable and do not require platforms to make decision about what content to censor.

This problem is usually called target-level sentiment analysis, in which a polarity label is assigned to a pair (text, target), where the target is present on the text.

The nonsense syllables that Ebbinghaus had invented as a tool can be seen to have acquired more ecological validity in an industrial age with expanding information demands, perhaps highlighting the practical importance of primary memory in daily life.

One might relate short-term memory to a pattern of neural firing that represents a particular idea and one might consider the idea to be in short-term memory only when the firing pattern, or cell assembly, is active ( Hebb, 1949 ).

This model assumes that, for any particular serial position within a list, the likelihood of successful short-term storage (S) and long-term storage (L) are independent, so that the likelihood of recalling the item is S+L−SL.

Each number was composed of either little X ’s or of little O ’s, and participants were asked to indicate as quickly as possible, using the keyboard, whether the number they saw was composed of X ’s or O ’s (cf. Navon, 1977 ).

One proposed explanation for these findings maintains that the conscious mind cannot apprehend complex structures of this sort, and so conscious search is bound to fail (cf. Reber, 1993 ).

Gain is a parameter in neural network modeling, which influences the probability that a neuron fires at a given activation level ( Hamker, 2005 ).

Actually, the practice is analogous to eliminating all the patients from a clinical trial that have died from the drug under investigation.

This is directly analogous to how simulation engines can be used for intuitive physics, to predict what will happen next in a scene or to infer objects’ dynamical properties from how they move.

The representations and algorithms used by this approach were more directly inspired by neuroscience than by cognitive psychology, although ultimately it would flower into an influential school of thought about the nature of cognition—parallel distributed processing (PDP) (McClelland et al., 1986; Rumelhart…

This can be seen as a trivial confirmation of the basic principle of statistical machine learning that your training and test data should come from the same distribution.

Carpenter's concept of unconscious cerebration and consequent interest in implicit memory derived from a more general attempt to relate physiology and psychology.

I present a number of core concepts from data science that are relevant to digital art history and the use of quantitative methods to study any cultural artifacts or processes in general.

I suggest that in digital art history we adapt the term “features” to refer to both information that can be extracted from objects through computer analysis and the already available metadata.

A user and the movies chosen are analogous to a document and the words in the document (respectively).

These results indicate that information diffusion is biased toward individuals who share a similar leaning in some social media, namely Twitter and Facebook. In contrast, in others—Reddit and Gab in our analysis—this effect is absent.

Then, we use these elements to assess echo chambers’ presence by looking at two different aspects: 1) homophily in interactions concerning a specific topic and 2) bias in information diffusion from like-minded sources.

This article suggests a computational method for the analysis of figurative language as a network, using methods from natural language processing (NLP), particularly topic classification and network analysis.

quantifying semantic change by evaluating word embeddings (PPMI, SVD, word2vec) against known historical changes

embeddings are high-dimensional vector-space models of text in which each unique word in the corpus is represented as a vector in a shared vector space

If we want to move beyond the use of ad hoc definitions, it can be useful to distinguish between what political scientists Adcock and Collier ( 2001 ) call the “background concept” and the “systematized concept.”

Model outputs tell us something about the texts, while a close reading of the texts alongside those outputs tells us something about the models that can be used for more effective model building.

More recently, the spatial analysis of texts via Geographic Information Systems (GIS) is trending as a research method.

Corresponding to the dose of toxicity that was ingested by organisms, the exposure dose of noise for organisms was the value of exposure sound level times exposure duration.

To determine MSI status, 114 intronic homopolymer repeat loci with adequate coverage on the CGP panel were analyzed for length variability and compiled into an overall MSI score via principal components analysis. The 114 loci were selected from a total set of 1897 that have adequate coverage on the FMI FoundationOne…

We finally sought to determine the effects of sequencing different amounts of the genome and how that might affect our ability to accurately determine TMB. We sampled the number of mutations that we would expect to see at different TMB levels (100 mutations/Mb, 20 mutations/Mb, 10 mutations/Mb) and at different…

Deep learning algorithms, in particular convolutional networks, have rapidly become a methodology of choice for analyzing medical images

Statistical methods (meta-analysis) may or may not be used to analyze and summarize the results of the included studies

(The remaining 30% arise from ‘spillovers’ benefiting the wider economy.) This level of benefit was calculated using an estimated lag of 17 years.

a 121-layer convolutional neural network trained on ChestX-ray14

outperforms the prior best method (a sliding-window convolutional network) on the ISBI challenge for segmentation of neuronal structures in electron microscopic stacks.

Randomised controlled trials, when appropriately designed, conducted, and reported, represent the gold standard in evaluating healthcare interventions

We defined the scope of the recommendations to cover three main study designs: cohort, case-control, and cross-sectional studies

By analogy with QED, one can also introduce a quantity called chirality6 that is formally a projection of σr on r and is positive (negative) for electrons (holes).

Since the COD identifier of a structure, once assigned, remains unchanged, a problem might arise when a deposited COD file needs to be changed for some reason, say, a syntax or data error must be corrected after the deposition. Currently, we have adopted a version control system called Subversion (Collins-Sussman et…

For anybody who wishes to use the COD and the PCOD databases, the collected files are presented using standard open protocols and formats. The database can be searched online on the COD server using a simple web-based search form, and the structural results can be downloaded either one by one or in a compressed .zip…

The apparent mean absolute error between experimental measurements and our calculations is 0.096 eV/atom. In order to estimate how much error to attribute to the DFT calculations, we also examine deviation between different experimental measurements themselves where multiple sources are available, and find a…

Consistent with observations in other domains of machine learning, we observe that our neural networks predictions improve as a power law with the amount of data.

the subtle and rich physics of quantum electrodynamics

Alternatively, empirical interatomic potentials that are based on classical principles require significantly fewer computational resources, which enables simulations to better describe dynamic processes over longer timeframes and on larger scales. Such methods, however, typically require a predefined connectivity…

This cost function was chosen because of its robustness in handling outliers in data sets, a property that achieves 2 to 4 times lower error upon training an ANI potential.

The choice of temperature is dependent on the intended use of the ANI potential being trained. However, it should be noted that this method of sampling the potential surface of a molecule is simply an approximation for generating structures.

Much can be borrowed from this legacy silicon TCAD, but there are significant challenges.

we review variational inference (VI), a method from machine learning that approximates probability densities through optimization

the impact of regularization bias and overfitting on estimation of the parameter of interest θ0 can be removed by using two simple, yet critical, ingredients: (1) using Neyman-orthogonal moments/scores that have reduced sensitivity with respect to nuisance parameters to estimate θ0, and (2) making use of cross-fitting…

The twenty-four data sets we study are drawn from a broad variety of different branches of human endeavor, including physics, earth sciences, biology, ecology, paleontology, computer and information sciences, engineering, and the social sciences.

One potential solution to this problem is a statistical concept called intention-to-treat (ITT) analysis.

ITT analysis includes every subject who is randomized according to randomized treatment assignment.

In this paper we derive a more efficient algorithm by using stochastic optimization (Robbins and Monro, 1951), a technique that follows noisy estimates of the gradient of the objective.

With one more detail—the idea of a natural gradient (Amari, 1998)—stochastic variational inference has an attractive form: 1.

the post-study probability that it is true is the positive predictive value, PPV

we explore the use of ideas from the machine learning literature to improve the performance of these classical methods with many covariates

the problems of endogeneity and measurement error. Our method extends the LISREL model

The noncognitive measures available in the data set are the Rotter Locus of Control Scale which was administered in 1979 and the Rosenberg 5 Self-Esteem Scale which was administered in 1980.

Our analysis of test scores uses five measures of cognitive skills (arithmetic reasoning, word knowledge, paragraph comprehension, mathematical knowledge, and coding speed) derived from the Armed Services Vocational Aptitude Battery (ASVAB), which was administered to all sample participants in 1980 and 1981.

Our approach builds on regression tree methods, modified to optimize for goodness of fit in treatment effects

What is needed is an electronic payment system based on cryptographic proof instead of trust

The author is indebted to Dr. David Gale for suggesting the use of Kakutani's theorem to simplify the proof and to the A. E. C. for financial support.

Reminders of money, relative to nonmoney reminders, led to reduced requests for help and reduced helpfulness toward others

The model of categorization in Cognitive Linguistics and sociocognitive terminology is based on Rosch’s (1978) Prototype Theory, which uses degrees of typicality as the configurational pattern for conceptual categories or domains.

Frames also fall within cognitive linguistic approaches, and are a type of cognitive structuring device based on experience that provide the background knowledge and motivation for the existence of words in a language as well as the way those words are used in discourse.

Probably the most successful concept is to use distributed representations of words [10].

combines the advantages of the two major model families in the literature: global matrix factorization and local context window methods

Indeed, priming between production and comprehension, just like priming between writing and speaking, supports the claim that both processes draw on common representations of linguistic information, particularly ones associated with syntax.

Another familiar case, involving even more painful risks, is establishing intimacy, as in beginning to use a familiar pronoun to someone in a language like French or German.

As Beaver and Zeevat note, the topic of local/intermediate accommodation has considerable parallels to the ongoing debate about whether there are “em- bedded implicatures”.

It then applies dualprocess models to the study of priming to illustrate the cognitive processing that occurs within media priming (and political priming).

Given that the System 1 and System 2 description encapsulates many of the propositions put forth in the ELM, the HSM, and other dual-process models, it will be utilized here.

One of the most influential and frequently cited of these is a paper by Johan Galtung and Mari Ruge (1965), “The Structure of Foreign News”, published more than 50 years ago.

Just as that study put Galtung and Ruge’s criteria to the test with an empirical content analysis of published news, this new study explores the extent to which Harcup and O’Neill’s revised list of news values remains relevant given the challenges (and opportunities) faced by journalism today, including the emergence…

Similar ideas about the compen- satory potential of media use was suggested in an early study by Kubey and Csikszentmihalyi (1990), who claimed that people were more likely to engage in bouts of heavy TV watching when they were in dysphoric states.

Williams, Yee, & Caplan (2008) have argued that game re- search needs to undergo the same transition as early communi- cation research did, where the direct effects model was made more nuanced by the addition of mediating variables.

What matters, Ingleby argues, are the fundamental principles which gov- ern the acquisition and interpretation of ‘‘findings’’; and these principles, although they are governed by matters of fact, are not themselves discovered empirically – they are as much philosophi- cal as scientific ones (p. 24).

The underlying Formula (2) can be interpreted as a conservation law for the relevance R in between layers of the feature processing.

The H-divergence resolves both problems associated with the L1 divergence. First, for hypothesis classes H of finite VC dimension, the H-divergence can be estimated from finite samples (see Lemma 1 below). Second, the H-divergence for any class H is never larger than the L1 divergence, and is in general smaller when H…

Our basic plan of attack will be as follows: Label each unlabeled source instance with 0 and unlabeled target instance as 1. Then train a classifier to discriminate between source and target instances. The H-divergence is immediately computable from the error.

We utilize such transferability of GNNs to accomplish the transferable property in our JSSP scheduler.

We use proximal policy optimization (PPO) [37] algorithm, a variant of policy-based RL, to train the GNN based state representation module and the parameterized decision-making policy jointly.

SMOTE and the extension of Borderline-SMOTE [30] create new instances by interpolating new points from existing instances via k-Nearest Neighbors.

For example, a human intelligence anecdote of transfer learning is illustrated in learning music.

A model based on n-ary relations, a normal form for data base relations, and the concept of a universal data sublanguage are introduced

The most commonly used metric is Average Precision (AP), derived from precision and recall. AP is usually evaluated in a category specific manner, i.e., computed for each object category separately. To compare performance over all object categories, the mean AP (mAP) averaged over all object categories is adopted as…

We take the attention approach proposed by a step further by proposing grid-based gating that allows attention gates to be more specific to local regions. This improves performance compared to gating based on a global feature vector.

Deep learning allows computational models of multiple processing layers to learn and represent data with multiple levels of abstraction mimicking how the brain perceives and understands multimodal information, thus implicitly capturing intricate structures of large‐scale data.

To further improve supervised learning methods for contact prediction, we borrow ideas from very recent breakthrough in computer vision.

Our network usually generates ∼70k anchors within a KITTI point cloud. Unfortunately, there are usually only a few ground truths, each of which generates only 4–6 positives. This leads to an extreme imbalance between the foreground and background classes.

Inspired by the original Linnaean biological taxonomy [ 4 ], we assigned the terms Kingdom, SuperClass, Class, and SubClass to denote the first, second, third and fourth levels of the chemical taxonomy, respectively.

using machine learning (and especially deep learning)

We apply such generative models to chemical design, using a pair of deep networks trained as an autoencoder to convert molecules represented as SMILES strings into a continuous vector representation

Variational autoencoders with recurrent neural network encoding/decoding were proposed by Bowman et al. in the context of written English sentences, and we followed their approach closely. 20

Such models usually also produce low-dimensional continuous representations of the data being modeled, allowing interpolation or analogical reasoning for natural images, 19 text, 20 speech, and music. 21 , 22

Deep learning has the potential to revolutionize quantum chemistry

presenting new results in random matrix theory, which are obtained using a quaternionic parameterization of the cavity method

Here we study the effect of modularity on the local stability of ecological dynamical systems, by presenting new results in random matrix theory, which are obtained using a quaternionic parameterization of the cavity method.

We have borrowed this analogy from the climate system that is now also believed to have distinct tipping elements 11 .

To detect alternative states in the intestinal bacteria, we used potential analysis that was recently applied to study analogous state shifts in climatology and forest ecosystems 13 , 14 .

which have been shown to display a very high homeostasis against random removals of nodes

The trophic organization of species-rich communities is similar to other complex network topologies (Albert et al 2000, Jeong et al 2000).

We build over Generative Adversarial Networks (GAN), which have shown the ability to learn to generate novel images simulating a given distribution

Berlyne emphasized that the most significant arousal-raising properties for aesthetics are novelty

biologically inspired vision models called Deep Neural Networks

Motivated by style transfer literature [27], we re-design the generator architecture in a way that exposes novel ways to control the image synthesis process.

In Digital Humanities (DH) research this process and its specific structure has to be represented on a data level.

we decided to use digital methods on DAH scholarship, namely text mining, to elucidate the historiographic and theoretical concerns in the uptake of computational methods in art history.

Irihapeti Ramsden and Māori nurses in the 1990s [74], and in 1992 the Nursing Council of New Zealand made cultural safety a requirement for nursing and midwifery education [32].

Leininger (1994) defined transcultural nursing as being a subfield of nursing, focusing on comparative study and analysis of different cultures and is the basis on which the theory of culture care diversity and universality was formed.

What is a concept? When defining of the term concept, I follow and adapt the approach of Deleuze and Guattari in their What Is Philosophy? (1991), in which they hold that “every concept has components and is defined by them” (p. 15).

Conceptual framework analysis offers a procedure of theorization for building conceptual frameworks based on grounded theory method.

In broad terms, saturation is used in qualitative research as a criterion for discontinuing data collection and/or analysis.1 Its origins lie in grounded theory (Glaser and Strauss 1967), but in one form or another it now commands acceptance across a range of approaches to qualitative research.

In contrast to data saturation and inductive thematic saturation, the first model of saturation considered, theoretical saturation—as based on the grounded theory notion of determining when the properties of theoretical categories are adequately developed— indicates that the process of analysis is at a more advanced…

Optimization is essential because creating coherent and contiguous relational knowledge is a complex combinatorial problem involving the identification, ranking, and sequential ordering of many interdependent elements and associated relationships.

Cognitive load theory was first proposed by a cognitive psychologist based on empirical research on short-term memory ability

in the literature on cognitive load theory

As part of the DeLone and McLean model (D&M) of information systems success, information quality was often used to measure system quality (DeLone and McLean, 2003).

Nutbeam [ 52 ] refers to the opposing medical and public health views on health literacy as respectively a "clinical risk", and a "personal asset" approach, and points out that they are rooted in the different traditions of clinical care, and adult learning and health promotion, respectively.

we collect data from Twitter related to both social network structure and tweet content for a large set of users (679,000) engaging with US politics

We link a representative online survey (N = 3500) to behavioral data on respondents’ Facebook sharing history during the campaign, avoiding known biases in self-reports of online activity.

Our BuzzFeed-based list began with 30 domains identified by that site’s reporting as purveyors of intentionally false election-related stories generating the most Facebook engagement. To do this, the journalists, led by Craig Silverman, used keywords and existing lists combined with the analytics service BuzzSumo. To…

For encoders, we use the multilingual mBERT (Devlin et al., 2019), and Hebrew-targeted encoders AlephBERT (Seker et al., 2022), HeRO (Shalumov and Haskey, 2023) and the base and large variants of DictaBERT (Shmidman et al., 2023).

Using the weighted log odds method proposed by Monroe et al. (2008), we identify the PDD target tokens most strongly associated with each political bloc.

using shrinkage estimation for dispersions and fold changes to improve stability

definitely to ascertain their statistical relations

Our method is based on the popular word embedding model word2vec, which is trained on a shallow two-layer neural network

However, the existing data cannot present the expression distribution of a certain immune-cell cluster across cancer types. In this case, researchers can use GEPIA2 to easily obtain the immune-cell cluster signature profile in a pan-cancer manner. For example, one can readily find that Th1-like signature in stomach…

in terms of classic methods in machine learning, such as supervised classification and reinforcement learning

This issue arises in almost any engineering discipline

The easy problems of consciousness are those that seem directly susceptible to the standard methods of cognitive science

total science is like a field of force whose boundary conditions are experience

Traditionally, networks of complex topology have been described using the random graph theory of Erd˝os and R´enyi (ER) (7), but in the absence of data on large networks the predictions of the ER theory were rarely tested in the real world.

Developing this metaphor, each intellectual construct whatever the origin would thus appear as a net whose mesh shape is different from another net or in other words, another discipline, another school of thought, another approach, etc.

social networks are robust to the removal of the strong ties, but fall apart following a phase transition if the weak ties are removed

Feld’s observation that ‘your friends have more friends than you’ is an important psychological paradox, applying to friendship as well as sexual partners.

the p-values corresponding to significances of 1 to 6

In a more abstract language, the algebra (with coefficients from Z2), 1-homologies and 1-cohomologies.

In general with this approach one can calculate quite accurately the low-lying (relatively small imaginary part) QNM modes, but it fails to give accurate results for higher-order modes.

From tests performed using polytropic stars to provide data for the above relations it was seen that these equations predict the masses and the radii of the polytropes usually with an error less than 10%. There is work underway towards extracting the parameters of the star from a noisy signal.

We proceed by extending the Skip-gram architecture to networks

The study of networks, in the form of mathematical graph theory, is one of the fundamental pillars of discrete mathematics.

Previously, a graph filtering technique called Planar Maximally Filtered Graph (PMFG) has been applied to many real-world data sets such as financial stock prices and gene expression to extract meaningful and relevant interactions.

These observations suggest that the biological networks may follow the similar evolutionary dynamics, and thus network analysis approaches from other domains are very helpful for understanding biological networks[ 4 ].

The first level deals with ultra-high frequency scales: that of elementary transactions (a level that in physics is called “microscopic”).

The use of the Hurst exponent is motivated by the relationship to diffusion properties of the integrated process.

Our main result is that log-volatility behaves essentially as a fractional Brownian motion with Hurst exponent H of order 0.1, at any reasonable time scale.

Analogous to axons in a biological brain, layers of the networks represent groups of "neurons" with each layer connected by "synapses" that transmit signals among neurons of different layers.

Mendelian randomisation is an analytical method that uses genetic variants as instrumental variables for modifiable risk factors that affect population health.

Mendelian randomisation uses genetic variation as a natural experiment to investigate the causal relations between potentially modifiable risk factors and health outcomes in observational data.

We define a dynamical model for the spreading of infections on scale-free networks

The epidemiological analysis of computer viruses has been the subject of a continuous interest in the computer science community [10,13–15], following mainly approaches borrowed from biological epidemiology [11].

the core problem of assignment of credit, a term from artificial intelligence that refers to the question

immediately forged a link with the dominant idea in biology: Charles Darwin’s natural selection, according to which adaptation arises via selection from a population that contains many heritable variants

The computational field of reinforcement learning has provided a normative framework within which both Pavlovian and operant conditioned behavior can be understood.

The view of operant behavior as a repertoire of emitted acts from which one is selected by reinforcement, immediately forged a link with the dominant idea in biology: Charles Darwin’s natural selection, according to which adaptation arises via selection from a population that contains many heritable variants, some…

The original Hume-Rothery solid-solution rule suggests that (rsolute−rsolvent)/rsolvent ≤ 15% is one of the necessary conditions for forming a binary solid solution.

In addition to the high- and medium-entropy alloys, there are now several other materials known to benefit from twinning, including copper thin films and 11–15 wt.% (Hadfield) Mn-steels (used in the mining industry for rock crushers because of their hardness and fracture resistance) and their modern variant known as…

Notably, the XRD pattern of the rinsed cathode differs from that of previously reported species (e.g., MnOOH, spinel ZnMn2O4 , birnessite, tunneled γ-ZnMnO2 , and layered L-ZnxMnO2 ) in discharged MnO2 electrodes (Supplementary Fig. 4d). Rietveld refinement of the XRD data of the discharged electrode suggests the…

A comparison of the crystallographic structure between β-MnO2 and Zn-buserite suggests that the co-insertion of Zn2+ and H2O and the dissolution of Mn distort the pyrolusite framework, leaving Mn vacancies in the upper/underlying layers and generating layered Zn-buserite. This tunnel-to-layer phase transition is…

For this purpose, we designed an in vitro RNA mixture experiment (Fig. 3a). Immune populations were purified from healthy donors’ peripheral blood; their RNAs were extracted and mixed in highly variable concentrations (from 0.7 to 46 % of the sample’s RNA). The RNA proportions of the populations were arranged in two…

Three criteria were then calculated for each feature (probe set) within the discovery set: a) the mean log2-expression difference between positive and negative samples (a threshold of 2 was applied); b) the area under the ROC curve (AUC) of the feature for the identification of the positive samples (threshold of…

The scRNA-seq microfluidics platform builds on the GemCode technology, which has been used for genome haplotyping, structural variant analysis and de novo assembly of a human genome.

While previous studies have used existing SNVs from DNA sequencing or large-scale copy number changes in the transcriptome data to distinguish cells by genotype, these methods cannot be applied to transplant samples where donor and host genotype is not known a priori, and when donor and host are closely matched in…

exact recovery may be obtained by solving a convex optimization problem

The form of H will be recognized as that of entropy as defined in certain formulations of statistical mechanics8 where pi is the probability of a system being in cell i of its phase space. H is then, for example, the H in Boltzmann’s famous H theorem.

These curves, analogous to the rate distortion curves, exists for every choice of the cardinality of ˜X.

using optimal matched filtering with waveforms predicted by general relativity

sampled, along with cosmological parameters, during Markov chain Monte Carlo (MCMC) exploration of the likelihood

we used a Monte Carlo simulation to understand how SNe Ia in our nearby and distant samples were c hosen

Our work is inspired by results in the emerging field of compressive sampling or compressed sensing, a new paradigm for acquiring information about objects of interest from what appears to be a highly incomplete set of measurements [10, 12, 16].

our paper has at least as much in common with the ergodic-theoretic approach as it does with the harmonic analysis approach

The interplay of statistical physics and (pseudo)-riemannian geometry occurs in the subject of Black Hole Thermodynamics

is relatively new, perhaps, is the realization that introducing them brings the psychophysical experiment under the rubric of detection, thereby rendering psychophysical

Fortunately, Peterson and Birdsall (15) have calculated these functions for a wide variety of signals presented in uniform gaussian noise.

The Sampling Theorem. We shall need one form of the so-called sampling theorem

Each abstract was categorized by two independent, anonymized raters

Data-driven approaches, most prominently deep learning, have become powerful tools for prediction in many

how tools developed in the context of differential privacy may be applied to fairness

concern over discrimination in machine learning has led to a large body of new work seeking to better understand and prevent it

We trained a convolutional neural network (CNN) to map raw pixels from a single front-facing camera directly to steering commands.

as well as a novel CNN architecture designed for robotic control

this study intends to further investigate which educational strategies can scientifically and effectively promote students’ mathematical creativity based on exploring the cognitive neural basis of creativity and mathematical competence through a cognitive neural meta-analytic approach

Cognitive neuroscience can not only examine behavioral changes but also study the correlation of these behavioral changes with brain structure and function.

Long short-term memory (LSTM) and the convolutional neural network (CNN) algorithm architecture were applied to identify behavioral sequences based on the data.

Germane cognitive load is defined as the amount of working memory capacity required for managing intrinsic load.

This phenomenon, referred to as effort discounting, relies on computations in which rewards are devalued by exerting effort.

According to Markus and Kitayama (2010) , an independent schema of self organizes behavior primarily in reference to an individual’s own thoughts and feelings and results in a weakened sense of in-group/out-group relationship so that people can move between in-group and out-group relatively easily.

In developing the priming framework, each type of prime is categorized by priming outcome: affective, behavioral, and cognitive, which follows suit with the tri-component ABC model of attitudes (Breckler, 1984).

Although procedural priming has been used in psychology, it has not been applied in a marketing context, despite its potential as a managerial tool for inducing favorable product inferences.

Using priming techniques from social psychology, we activate the concept of cooperation and explore the extent to which this intervention brings about changes in people’s voluntary contributions to the public good and self-reported emotional responses.

To situate our approach within existing methodological traditions, we note that our use of LLM-based generative agents as substitutes for human participants builds on the lineage of agent-based modeling in experimental economics, while integrating recent advances in natural language reasoning through prompt…

Our theoretical position draws on the priming literature in social science, which posits that individuals have multiple identities, the salience of which can influence their political preferences on a given political issue.

The orientation of today’s consumers with respect to companies enjoying platform power can perhaps best be made by analogy to what Hooghe and Marks (2009) called the permissive consensus in public opinion.

A single coder (CS), trained in qualitative analysis methods, analyzed the transcripts and identified themes using an open coding process, which does not use a priori codes or codes created prior to the analysis and places an emphasis on information that can be extracted directly from the data.

The interviews were conducted by 20 undergraduate researchers trained in qualitative methods and the use of the interview survey guide described above. None of the authors conducted the interviews. All interviews were conducted via Zoom [22] and were audio recorded. The recordings were later transcribed using Otter.ai…

Foremost among these experiments, the Ultimatum Game provides a pair of anonymous subjects with a sum of real money for a one-shot interaction.

we use a simple, robust sentiment analysis tool to extract the reader-perceived emotional content of written stories as they unfold on the page

factorization can be reduced to finding the order of an element

the Linear Quadratic Regulator (LQR) with unknown dynamics, perhaps the simplest and best-studied problem in optimal control

at leveraging machine learning to solve combinatorial optimization problems

Building on the health risk literature, we suggest that processing health messages that convey high (vs. low) levels of risk consumes more self-control resources and thus will undermine subsequent self-control in performing health behaviors unrelated to the depleting message.

To understand audience members’ perceptions of influencer-produced sponsored content from a variety of perspectives, this research combined theoretical insights from several fields, including corporate communication, psychology, media studies, marketing research, and advertising.

However, in some cases the SD-2- AFC produced lower d-prime values indicating lower absolute levels of sensory differentiation.

As such, behavioural economics has been mostly concerned, broadly, with how people respond to incentives – and the landmark model in this field, prospect theory (Kahneman & Tversky, 1979), describes how people actually make risky financial decisions.

Nudging is attracting considerable interest due to its understanding and application of heuristic biases among consumers

Our study will further contribute to research by adapting communication accommodation theory (Giles et al., 2010) to the context of human-AI interaction, thereby showing that adapting the CA’s communication style to users has the potential to positively influence their user experience.

Psychologists first applied the theory in studies of perception, where subjects discrimi nated between signals (stimuli) and noise (no stimuli).

The winning coalition associated with an object or event would correspond to the winning party, which would remain in power for some time and would attempt to influence and control future events.

Drawing on work from psychology (Norman H. Anderson and Stephen Hubert 1963, and W. A. Watts and W. J. McGuire 1964), political scientists have constructed models of online processing of political information

Most of us would describe this kind of application of the law as a function of an ideal Weberian bureaucracy.

According to most systems of modal logic, if there exists even a single retrospective law, it follows that retrospective laws certainly could exist—in virtue of axiom M.

The aim of the article is to show how neuroscience techniques can contribute to economic experiments, especially those concerning decision making. The overview and presentation of the possibilities of such tools is shown regarding different stages of the decision making process and related experimental studies.

While the principles of evidence-based medicine have substantially shaped clinical decision-making, their direct transfer to educational contexts has proven conceptually methodologically challenging.

Designed as a semi-systematic evaluation, this paper analyzes and compares 22 guidelines, highlighting overlaps but also omissions. As a result, I give a detailed overview of the field of AI ethics. Finally, I also examine to what extent the respective ethical principles and values are implemented in the practice of…

We unify concepts from many-body Hamiltonians with purpose-designed deep tensor neural networks, which leads to size-extensive and uniformly accurate (1 kcal mol −1 ) predictions in compositional and configurational chemical space for molecules of intermediate size.