Cortical Membrane Potential Signature of Optimal States for Sensory Signal Detection

Cortical Membrane Potential Signature of Optimal States for Sensory Signal Detection McGinley David McCormick

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Cortical Membrane Potential Signature of Optimal States for Sensory Signal Detection 2015 Neuron 10.1016/j.neuron.2015.05.038 McGinley2015-cortical-membrane-potential-signature-of-opt McGinley2015-cortical-membrane-potential-signature-of-opt.txt, the project's staged copy 8aeb7f81b54b76b6e90cf938e3530fbdc0e4530c not-redistributable neuroscience

the paper's own words

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0 spans located by searching the stored text for the quote's exact words, allowing any whitespace between them what the cortex is doing at the moment an animal is best at detecting a faint sound, and how that state can be measured continuously from outside Quotation withheld because this record is not cleared for redistribution. what the synaptic and circuit basis is of the classical inverted-U between arousal and detection performance Quotation withheld because this record is not cleared for redistribution. arousal read continuously from the pupil predicts membrane potential, sensory response and behaviour, and all three are optimal at an intermediate level where the cortex is stably hyperpolarised Quotation withheld because this record is not cleared for redistribution. mechanism Quotation withheld because this record is not cleared for redistribution. arousal-dependent auditory signal detection Quotation withheld because this record is not cleared for redistribution. electrophysiology electrophysiology Quotation withheld because this record is not cleared for redistribution. mechanisms rising arousal suppresses low-frequency cortical rhythms, letting cortico-cortical and cortico-subcortical circuits interact more reliably and so producing larger, more precise sensory responses status: the paper's own words: We hypothesize that Quotation withheld because this record is not cleared for redistribution. mechanisms at hyper-arousal the depolarization is carried by task-unrelated synaptic activity that raises membrane variance and thereby disrupts sensory-evoked neuronal interactions Quotation withheld because this record is not cleared for redistribution. mechanisms the opposing arousal-driven changes in thalamic gain and cortical depolarization combine to generate the U and inverted-U curves relating arousal to neural and behavioural performance status: the paper's own words: We propose that Quotation withheld because this record is not cleared for redistribution. mechanisms the lag between cortical depolarization and pupil dilation arises because pupillary and eyelid muscles respond slowly to sympathetic and parasympathetic drive Quotation withheld because this record is not cleared for redistribution. membrane potential and its variance trace a U-shaped relationship against arousal level as indexed by normalized pupil diameter Quotation withheld because this record is not cleared for redistribution. so the signal-to-noise ratio of an evoked response is high at that state, from both suppressed background and larger responses Quotation withheld because this record is not cleared for redistribution. at high arousal the cortex depolarises, which may raise single-neuron responsiveness while degrading the interactions that carry a sensory response Quotation withheld because this record is not cleared for redistribution. and thalamic responses fall with arousal and fall further with walking, so part of the cortical decline is inherited Quotation withheld because this record is not cleared for redistribution. The proposed thalamo-cortical account of the U-shaped relationship has not been tested across behavioural contexts. what this limits: the thalamo-cortical account of the U-shaped relationship: FURTHER EXAMINATION OF THIS HYPOTHESIS, PARTICULARLY THE INFLUENCE OF BEHAVIORAL CONTEXT, REMAINS TO BE DONE Quotation withheld because this record is not cleared for redistribution. The paper cannot resolve why locomotion enhances visual but suppresses auditory cortical responses. what this limits: the visual-versus-auditory locomotion discrepancy: IT IS CURRENTLY UNCLEAR WHETHER THESE APPARENTLY OPPOSING RESULTS REFLECT VARIATIONS BETWEEN SENSORY SYSTEMS IN CORTICAL OR SUBCORTICAL INFLUENCES OF LOCOMOTION AND/OR AROUSAL Quotation withheld because this record is not cleared for redistribution. The neuromodulatory pathway linking pupil-indexed arousal to the cortical inhibitory circuitry was not established. what this limits: the neuromodulatory account: THE INFLUENCE OF NOREPINEPHRINE, WHICH IS THOUGHT TO CONTROL PUPIL DIAMETER, ON CORTICAL INHIBITORY CIRCUITS REMAINS TO BE DETERMINED Quotation withheld because this record is not cleared for redistribution. whether the opposing visual and auditory results reflect sensory systems, subcortical influences or the arousal level during stillness is stated to be unclear what this limits: the generalisation across cortical areas: in visual cortex LOCOMOTION IS ASSOCIATED WITH ENHANCED SENSORY-EVOKED VISUAL RESPONSES, while in auditory cortex the effect runs the other way Quotation withheld because this record is not cleared for redistribution. laminar position and cell type are named as a second possible source of between-study variation, with their layer 5 cells behaving unlike layer 2/3 visual cells what this limits: the same scope as limitations[3], with a second candidate source: ANOTHER POSSIBLE SOURCE OF VARIATION BETWEEN STUDIES ... IS THE LAMINAR POSITION AND CELL TYPE OF THE RECORDED NEURONS Quotation withheld because this record is not cleared for redistribution. the influence of behavioural context on the proposed account remains to be done what this limits: the proposed U-shaped account: FURTHER EXAMINATION OF THIS HYPOTHESIS, PART[icularly under behavioural context], remains to be done Quotation withheld because this record is not cleared for redistribution. the peak of one measure out of thirteen, behavioural discriminability, sits at a significantly smaller pupil diameter than the rest what this limits: the claim that the measures share an optimal arousal level: WE DID NOT FIND STATISTICALLY SIGNIFICANT DIFFERENCE BETWEEN 12 OF THE 13 BEHAVIORAL OR PHYSIOLOGICAL measures - so one of thirteen peaks elsewhere, and it is the behavioural one Quotation withheld because this record is not cleared for redistribution. pupillometry as a continuous index of autonomic state, imported to index cortical membrane potential rather than emotion Quotation withheld because this record is not cleared for redistribution. sharp-wave ripple rate as an independent state variable, used to validate the pupil rather than as the object of study Quotation withheld because this record is not cleared for redistribution. response latency on hit trials plotted against pupil diameter, showing short latency licks and a large decrease in variability of lick latency at intermediate diameters Quotation withheld because this record is not cleared for redistribution. responses sorted by state against responses averaged over all states, where no effect would be a diagonal of slope one Quotation withheld because this record is not cleared for redistribution. eyelid opening measured IN DARKNESS, alongside the pupil recording eliminates: illumination change as the cause of the pupil dilations - an eye movement changes how much light reaches the pupil, so a dilation time-locked to behaviour could be an optical consequence of looking elsewhere · outcome (stated by the tagger, no quotation): held Quotation withheld because this record is not cleared for redistribution. pupil pupil Quotation withheld because this record is not cleared for redistribution. hyperpolarized hyperpolarized Quotation withheld because this record is not cleared for redistribution. evoked evoked Quotation withheld because this record is not cleared for redistribution. hit hit Quotation withheld because this record is not cleared for redistribution. pupil derivative → pupil diameter THE INDEXING / PROXY RELATION - 'from' STANDS IN FOR 'to'. We have no type for it: 'causes' asserts production, and 'operationalised-as' says the authors CHOSE a measure, whereas a proxy claim says THIS STANDS IN FOR WHAT WE ACTUALLY CARE ABOUT AND WE KNOW IT IS NOT THE SAME THING. Measured at 8% of papers. A PROXY FOR ITSELF, DISPLACED IN TIME: 'the explanatory power of the pupil derivative occurs because it serves as a proxy for the pupil diameter approximately 1 second later'. The two endpoints are the same measurement at different lags, which is a substitution no vocabulary of concepts would catch. Quotation withheld because this record is not cleared for redistribution. A LITERATURE'S CONTRADICTIONS ATTRIBUTED TO A VARIABLE NOBODY MEASURED: state fluctuates continuously and in seconds, which produces variability between studies and between moments inside one study, and has not been accounted for Quotation withheld because this record is not cleared for redistribution. and one earlier report is named as having recorded across un-anaesthetised states without quantifying the arousal of the animals at all Quotation withheld because this record is not cleared for redistribution. A BINARY CATEGORY IS DISSOLVED INTO A CONTINUUM: the same pupil measure had been used to sort trials into aroused and unaroused, and is used here as a graded quantity Quotation withheld because this record is not cleared for redistribution. AND A WHOLE LITERATURE'S INDEPENDENT VARIABLE IS RE-IDENTIFIED: the often reported effects of movement may not result from movement per se but from arousal, with one exception named and kept Quotation withheld because this record is not cleared for redistribution. THE SHAPE OF THE EFFECT BREAKS THE SUMMARY STATISTIC: because the relation is U-shaped the correlation is positive over one half of the range and negative over the other, which forced a sliding window rather than one coefficient Quotation withheld because this record is not cleared for redistribution. A RIVAL MEASURE IS TESTED AND THEN EXPLAINED AWAY: the derivative of the pupil predicts less than the diameter, and correlates with the diameter a second later, so its explanatory power may be entirely borrowed Quotation withheld because this record is not cleared for redistribution. THE MEASURE IS VALIDATED THROUGH A CHANNEL WHERE THE CONFOUND CANNOT OPERATE: pupil dilation could be a response to light, so eyelid opening was measured in darkness, where dilation is saturated, and moved the same way Quotation withheld because this record is not cleared for redistribution. and the recording artefact is ruled out by timing rather than by argument - the depolarisation begins before the behavioural event and returns after it Quotation withheld because this record is not cleared for redistribution. THIRTEEN MEASURES ARE ASKED WHETHER THEY PEAK IN THE SAME PLACE: twelve are statistically indistinguishable and the thirteenth is not, with an interpretation offered for the one Quotation withheld because this record is not cleared for redistribution. and the state measure is normalised within session because its maximum drifts between days and animals, so every number here is a fraction of that animal's own range Quotation withheld because this record is not cleared for redistribution. claim_type: mechanism a second reading reaching the same value. Recorded: mechanism — note: a second reading reaching the same value from a different sentence. Not applied - a person decides. Quotation withheld because this record is not cleared for redistribution. method: pupil diameter as a continuous state measure, validated against hippocampal ripple rate and against eyelid opening in darkness, related to membrane potential, evoked responses and trial outcome a second reading DIFFERING from the recorded value. Recorded: electrophysiology — note: a second reading, verbatim-verified, disagreeing with the value on the record. Not applied - a person decides. Quotation withheld because this record is not cleared for redistribution. phenomenon: the inverted-U between arousal and performance, and its cortical signature a second reading DIFFERING from the recorded value. Recorded: arousal-dependent auditory signal detection — note: a second reading, verbatim-verified, disagreeing with the value on the record. Not applied - a person decides. Quotation withheld because this record is not cleared for redistribution. extends → Reimer et al. (2014) Quotation withheld because this record is not cleared for redistribution. contradicts → Reimer et al. (2014) Quotation withheld because this record is not cleared for redistribution. replicates → Williamson et al. (2014) Quotation withheld because this record is not cleared for redistribution. explains-away → the rate of change of pupil diameter as the better index of cortical state, which is shown to be a lagged proxy for the diameter itself Quotation withheld because this record is not cleared for redistribution. reconciles → the divergent reports of cortical membrane potential in waking animals, by supplying the continuously varying state variable none of them measured Quotation withheld because this record is not cleared for redistribution. critiques → studies of the effects of walking and whisking on sensory responses, which most likely involved large uncontrolled changes in arousal differs in: THE AXIS IS AROUSAL AS AN UNCONTROLLED VARIABLE. 'Quotation withheld.' A whole literature's independent variable is shown to have carried a second one with it - established by THIS paper's own pupil measurement, which is why nobody could have controlled for it earlier. Quotation withheld because this record is not cleared for redistribution. supports → the classical Yerkes-Dodson inverted-U between arousal and performance, by giving it a cellular and network basis Quotation withheld because this record is not cleared for redistribution. qualifies → the opposing visual and auditory locomotion results, which are left explicitly unresolved differs in: THE AXIS IS THE CORTICAL AREA, AND THE SIGN REVERSES ACROSS IT. 'Quotation withheld (over non-locomotion), while in auditory cortex locomot[ion suppresses them].' The paper poses the question, gives the opposite findings, and LEAVES IT UNRESOLVED - so 'locomotion modulates sensory responses' is true with two opposite signs and the area is not optional. Quotation withheld because this record is not cleared for redistribution. state —operationalised-as→ arousal state arousal strength of the relation: 1 · note: A LITERATURE'S CONTRADICTIONS ATTRIBUTED TO A VARIABLE NOBODY MEASURED: it fluctuates continuously and rapidly, producing variability between studies and between moments within one, and has not been accounted for Audit 2026-09-28: DOUBTFUL - read against its span and kept, but the span writes 'state (arousal)'; operationalised-as is loose. Quotation withheld because this record is not cleared for redistribution. pupil —operationalised-as→ state pupil state strength of the relation: 1 · note: chosen for being non-invasive and continuous, and for tracking state changes whether or not they come with overt movement Quotation withheld because this record is not cleared for redistribution. EIS —operationalised-as→ eyelid EIS eyelid strength of the relation: 1 · note: and a cheaper proxy is then derived from the light reflected off the eye, so the measure can travel Audit 2026-09-28: DOUBTFUL - read against its span and kept, but reflected infrared light is a proxy for lid opening; operationalised-as is loose. Quotation withheld because this record is not cleared for redistribution. pupil —contrasted-with→ derivative pupil derivative differs in: THE AXIS IS WHICH PREDICTOR ADDS ANYTHING, AND THE ANSWER IS THAT ONE DOES NOT. 'Factoring in both the pupil diameter and its derivative explained 40+/-6% of the variance of power in the 2-10 Hz band, which was statistically larger than the amount explained by pupil derivative (p<0.0005), but not pupil diameter alone (p=0.36).' Adding the derivative to diameter does not improve on diameter alone - a null reported in the same sentence as the significant comparison, and the pair is only distinguishable because both tests are given. · strength of the relation: 1 · note: A RIVAL MEASURE TESTED HEAD TO HEAD: the diameter explains 34 percent of the variance in low-frequency power, the derivative about half that, and both together add nothing over the diameter alone Audit 2026-09-28: DOUBTFUL - read against its span and kept, but the span compares pupil diameter with its derivative as indicators; contrasted-with is loose. Quotation withheld because this record is not cleared for redistribution. microdilation —causes→ membrane potential microdilation membrane potential status: ASSOCIATIONAL AND TIME-LOCKED, WHICH IS NOT THE SAME AS CAUSAL: microdilations 'were reliably associated with 5-20 mV time-locked depolarization'. Tight temporal coupling in 16 neurons; nothing was manipulated to establish which leads. · strength of the relation: 1 · note: 5 to 20 mV depolarisations time-locked to them, and leading the pupil by about a second Audit 2026-09-28: DOUBTFUL - read against its span and kept, but the span says microdilations were ASSOCIATED with depolarization; causes overstates it. Quotation withheld because this record is not cleared for redistribution. MG —contrasted-with→ ACtx MG ACtx strength of the relation: 1 · note: thalamic responses fall steadily with arousal and fall further during walking, so part of the cortical decline is inherited and part is not Quotation withheld because this record is not cleared for redistribution. walking —is-a→ movement walking movement strength of the relation: 1 · note: since walking only ever happened at large pupil diameters, previous studies of movement effects most likely involved large changes in arousal Quotation withheld because this record is not cleared for redistribution. whisking —distinct-from→ arousal whisking arousal strength of the relation: 0.9 Audit 2026-09-28: DOUBTFUL - read against its span and kept, but the span argues effects may come from arousal rather than movement; distinct-from is loose. Quotation withheld because this record is not cleared for redistribution. hit —contrasted-with→ false alarm hit false alarm strength of the relation: 1 · note: with hit and miss trials resampled to equal target level distributions, so loudness cannot be what separates them Quotation withheld because this record is not cleared for redistribution. arousal —causes→ detection arousal detection strength of the relation: 1 · note: the optimum is 40 to 60 percent of full dilation, for the neurons and for the behaviour alike Audit 2026-09-28: DOUBTFUL - read against its span and kept, but the span says intermediate arousal is optimal for detection; causes is loose and unsigned. Quotation withheld because this record is not cleared for redistribution. evoked —distinct-from→ spontaneous evoked spontaneous strength of the relation: 1 · note: and the optimum is a ratio: background suppressed AND response enhanced, not either alone Audit 2026-09-28: DOUBTFUL - read against its span and kept, but the span attributes high SNR to suppression of spontaneous activity; distinct-from is loose. Quotation withheld because this record is not cleared for redistribution. depolarization —causes→ reliability depolarization reliability strength of the relation: 0.7 · note: the proposed cost of the depolarised state - single neurons more responsive, their interactions less so Audit 2026-09-28: DOUBTFUL - read against its span and kept, but the span discusses possible detrimental effects of depolarization; causes is loose. Quotation withheld because this record is not cleared for redistribution. coherence coherence Quotation withheld because this record is not cleared for redistribution. correlation correlation Quotation withheld because this record is not cleared for redistribution. ANOVA ANOVA Quotation withheld because this record is not cleared for redistribution. standard deviation standard deviation Quotation withheld because this record is not cleared for redistribution. standard error of the mean standard error of the mean Quotation withheld because this record is not cleared for redistribution. bootstrap confidence interval bootstrap confidence interval Quotation withheld because this record is not cleared for redistribution. resampling with replacement resampling with replacement Quotation withheld because this record is not cleared for redistribution. signal detection theory measures (d-prime and criterion) signal detection theory measures (d-prime and criterion) Quotation withheld because this record is not cleared for redistribution. F-test F-test Quotation withheld because this record is not cleared for redistribution. explained variance explained variance Quotation withheld because this record is not cleared for redistribution. cross-correlation cross-correlation Quotation withheld because this record is not cleared for redistribution. coherence coherence Quotation withheld because this record is not cleared for redistribution. cross correlation cross correlation Quotation withheld because this record is not cleared for redistribution. explained variance explained variance Quotation withheld because this record is not cleared for redistribution. resampled resampled Quotation withheld because this record is not cleared for redistribution. Pupil diameter showed a strong inverse relationship to the rate of fast ripples, with a peak coherence of about 0.78 at low frequencies. Quotation withheld because this record is not cleared for redistribution. Auditory cortical membrane potential and its variance follow a U-shaped function of arousal, being most hyperpolarized and least variable at intermediate pupil diameter. Quotation withheld because this record is not cleared for redistribution. Brief spontaneous pupil microdilations in still animals are locked to 5-20 mV depolarizations of cortical neurons. Quotation withheld because this record is not cleared for redistribution. The cortical depolarization leads the pupil dilation by roughly one second, so the membrane potential change comes first. Quotation withheld because this record is not cleared for redistribution. Sound-evoked synaptic responses in auditory cortex are largest at intermediate pupil diameter and shrink with either constriction or further dilation. Quotation withheld because this record is not cleared for redistribution. Behavioural hit rate on the tone-in-noise detection task follows an inverted-U in pupil diameter at every tone intensity. Quotation withheld because this record is not cleared for redistribution. Just before correct detections the membrane potential was more hyperpolarized and less variable than before false alarms. Quotation withheld because this record is not cleared for redistribution. Pupil diameter predicts trial-to-trial cortical response variability at least as well as walking status and absorbs walking's predictive power. Quotation withheld because this record is not cleared for redistribution. The optimal arousal band, for both neural coding and behaviour, corresponds to pupils dilated to 40-60% of maximum. Quotation withheld because this record is not cleared for redistribution. Thalamic (medial geniculate) sound responses decline steadily as pupil diameter increases and are suppressed further during walking. Quotation withheld because this record is not cleared for redistribution. Raw pupil diameter explains about twice as much of the low-frequency membrane-potential power as the rate of change of pupil diameter does. Quotation withheld because this record is not cleared for redistribution. Mice only walked when their pupils were large, so locomotion in this preparation is always accompanied by high arousal. Quotation withheld because this record is not cleared for redistribution. APPARENTLY DIVERGENT RESULTS ARE ATTRIBUTED TO A VARIABLE NOBODY ACCOUNTED FOR: state fluctuates continuously and rapidly, giving variability between studies and between moments within individual studies Quotation withheld because this record is not cleared for redistribution. with the divergent reports themselves laid out first, across species and sensory systems WHOSE RESULT THIS IS: Steriade et al., 2001 ), but recent work in rodent sensory cortical areas has revealed - THE EVIDENCE FOR THIS ROW ATTRIBUTES THE WORK TO SOMEBODY ELSE. The cited name is the subject of a result verb and the sentence carries no first-person marker, so the finding, quantity or definition is the CITED author's rather than this record's. The claim is true and the quote is verbatim - what is wrong is whose result the corpus says it is. Nothing edited, nothing withdrawn: the row is marked so a page can name the source. Where the record is a commentary or review, its claim relations layer usually already names the paper being discussed - the record knows at one layer and forgets at another. Quotation withheld because this record is not cleared for redistribution. and one earlier study named as having recorded across un-anaesthetised states without quantifying arousal Quotation withheld because this record is not cleared for redistribution. walking increases visual cortical responses and decreases auditory ones, which is the contradiction in view Quotation withheld because this record is not cleared for redistribution. A BINARY CATEGORY IS DISSOLVED INTO A CONTINUUM: the same pupil measure had been used to sort trials into aroused and unaroused Quotation withheld because this record is not cleared for redistribution. pupil diameter tracks hippocampal ripple rate inversely, supporting the view that it may be a useful indicator of brain state Quotation withheld because this record is not cleared for redistribution. THE LIGHT CONFOUND IS REMOVED BY CHANGING CHANNEL: eyelid opening measured in darkness, where dilation is saturated, moves the same way Quotation withheld because this record is not cleared for redistribution. and a proxy is derived from infrared light reflected from the eye, termed eye-indexed state Quotation withheld because this record is not cleared for redistribution. the pupil is normalised within session because its maximum drifts between days and animals Quotation withheld because this record is not cleared for redistribution. brief dilations are time-locked to 5 to 20 mV depolarisations that lead them by about a second Quotation withheld because this record is not cleared for redistribution. membrane potential and its variance both trace a U against arousal, most hyperpolarised and least variable in the middle Quotation withheld because this record is not cleared for redistribution. THE SHAPE OF THE EFFECT BREAKS THE SUMMARY STATISTIC: the correlation is positive over one half of the range and negative over the other, forcing a sliding window Quotation withheld because this record is not cleared for redistribution. and layer 5 multi-unit firing shows the same U, lowest at intermediate pupil Quotation withheld because this record is not cleared for redistribution. THE RECORDING ARTEFACT IS RULED OUT BY TIMING: the depolarisation starts before the behavioural event and returns after it Quotation withheld because this record is not cleared for redistribution. and spike threshold barely tracks the pupil, varying instead with the rate of rise into threshold Quotation withheld because this record is not cleared for redistribution. A RIVAL MEASURE IS TESTED HEAD TO HEAD: raw pupil diameter and the rate of change of pupil diameter are both compared to membrane power at 2-10 Hz, and factoring in both is not statistically better than the diameter alone Quotation withheld because this record is not cleared for redistribution. AND THEN EXPLAINED AWAY: the derivative correlates with the diameter 1.3 s later and not with it at the same moment Quotation withheld because this record is not cleared for redistribution. evoked spikes and synaptic responses are largest at moderate pupil diameters and smaller in both directions Quotation withheld because this record is not cleared for redistribution. with evoked rate, reliability and gain all following the same inverse U Quotation withheld because this record is not cleared for redistribution. and the gain model is built so that no effect is a diagonal of slope one Quotation withheld because this record is not cleared for redistribution. thalamic responses fall steadily as the pupil dilates and are suppressed further during walking Quotation withheld because this record is not cleared for redistribution. THE PUPIL SUBSUMES THE OLDER VARIABLE: walking status adds 20 percent explained variance, pupil adds 28, and both together (29) are not significantly more than pupil alone Quotation withheld because this record is not cleared for redistribution. lick latency is shortest and least variable at intermediate diameters, for hits and false alarms alike Quotation withheld because this record is not cleared for redistribution. membrane potentials are most hyperpolarised and least variable before hits, with the largest evoked responses Quotation withheld because this record is not cleared for redistribution. and hit and miss trials are resampled to equivalent target tone level distributions Quotation withheld because this record is not cleared for redistribution. THIRTEEN MEASURES ARE ASKED WHETHER THEY PEAK IN THE SAME PLACE: twelve are indistinguishable and only behavioural discriminability sits lower Quotation withheld because this record is not cleared for redistribution. the optimum is 40 to 60 percent of full dilation, for the neurons and the behaviour alike Quotation withheld because this record is not cleared for redistribution. which suggests a cellular and network basis for the classical inverted-U Quotation withheld because this record is not cleared for redistribution. and at the best state the signal-to-noise ratio of evoked cortical responses is high, owing both to the suppression of spontaneous activities and the enhanced amplitude of sensory evoked responses Quotation withheld because this record is not cleared for redistribution. A LITERATURE'S INDEPENDENT VARIABLE IS RE-IDENTIFIED: reported effects of movement may not result from movement per se but from arousal Quotation withheld because this record is not cleared for redistribution. with previous walking studies described as having most likely involved large uncontrolled changes in arousal Quotation withheld because this record is not cleared for redistribution. and one arousal-independent walking effect, on thalamic responses and decision bias, named and kept Quotation withheld because this record is not cleared for redistribution. laminar position and cell type are named as a second source of between-study variation Quotation withheld because this record is not cleared for redistribution. and whether the opposing visual and auditory results reflect systems, subcortical influence or arousal during stillness is left open Quotation withheld because this record is not cleared for redistribution. the proposed cost is that depolarisation may raise single-neuron responsiveness while harming sensory-evoked neuronal interactions Quotation withheld because this record is not cleared for redistribution. and the influence of behavioural context on the account remains to be done Quotation withheld because this record is not cleared for redistribution. the classical Yerkes-Dodson curve predicts optimal performance at intermediate arousal Quotation withheld because this record is not cleared for redistribution. microdilations microdilations Quotation withheld because this record is not cleared for redistribution. eye-indexed state eye-indexed state Quotation withheld because this record is not cleared for redistribution. Yerkes-Dodson curve Yerkes-Dodson curve Quotation withheld because this record is not cleared for redistribution. canonical wakeful state canonical wakeful state Quotation withheld because this record is not cleared for redistribution. EIS EIS Quotation withheld because this record is not cleared for redistribution. microdilation microdilation Quotation withheld because this record is not cleared for redistribution. gain gain Quotation withheld because this record is not cleared for redistribution. arousal arousal Quotation withheld because this record is not cleared for redistribution. target tone level target tone level Quotation withheld because this record is not cleared for redistribution. intracellular injection of current intracellular injection of current Quotation withheld because this record is not cleared for redistribution. spontaneous activity spontaneous activity Quotation withheld because this record is not cleared for redistribution. behavioral performance behavioral performance Quotation withheld because this record is not cleared for redistribution. pupil diameter pupil diameter Quotation withheld because this record is not cleared for redistribution. pupil pupil Quotation withheld because this record is not cleared for redistribution. membrane potential membrane potential Quotation withheld because this record is not cleared for redistribution. gain gain Quotation withheld because this record is not cleared for redistribution. latency latency Quotation withheld because this record is not cleared for redistribution. reliability reliability Quotation withheld because this record is not cleared for redistribution. 0.78 ± 0.07 — peak coherence between pupil diameter and hippocampal fast-ripple rate at low frequencies Quotation withheld because this record is not cleared for redistribution. R=−0.94 +/− 0.03 — correlation between pupil diameter and hippocampal ripple rate Quotation withheld because this record is not cleared for redistribution. 5–20 mV — amplitude of the membrane-potential depolarizations time-locked to pupil microdilations Quotation withheld because this record is not cleared for redistribution. 1.1 ± 0.1 s — lead time by which cortical depolarization precedes pupil dilation or eyelid opening Quotation withheld because this record is not cleared for redistribution. 34±7% versus 18±4% — variance in 2-10 Hz membrane-potential power explained by pupil diameter versus by its temporal derivative Quotation withheld because this record is not cleared for redistribution. −74 ± 1.2 mV — average membrane potential corresponding to zero change on the arousal heatmap Quotation withheld because this record is not cleared for redistribution. 37 ± 17%, 160 ± 120%, and 94 ± 55% — gain in explained variance for d-prime, bias and lick latency when pupil diameter is known in addition to tone intensity Quotation withheld because this record is not cleared for redistribution. ~0.15 mm to ~1.8 mm — range over which pupil diameter varied in waking mice under constant low light Quotation withheld because this record is not cleared for redistribution. 40–60% — fraction of full dilation that marks the optimal arousal band for neural coding and behaviour Quotation withheld because this record is not cleared for redistribution. 40–60% — of full dilation - the optimum, and the same range for the neurons and for the behaviour Quotation withheld because this record is not cleared for redistribution. 34±7% — variance in low-frequency membrane power explained by pupil diameter, against about half that for its derivative Quotation withheld because this record is not cleared for redistribution. 1.3 ± 0.7 seconds — the lag by which the pupil derivative leads the diameter - which is why it looked like a better predictor Quotation withheld because this record is not cleared for redistribution. 1.1 ± 0.1 s — by how much the cortical depolarisation precedes the pupil dilation it is locked to Quotation withheld because this record is not cleared for redistribution. 20 ± 8% — explained variance added by knowing walking status, against 28 percent for pupil diameter and nothing for both together Quotation withheld because this record is not cleared for redistribution. 12 of the 13 — measures whose optimum could not be distinguished from one another Quotation withheld because this record is not cleared for redistribution.

The full text of this article is not redistributable, so it is not included here. The evidence sentences are withheld with it; the tag layer and its grounding status remain. The article itself is at https://doi.org/10.1016/j.neuron.2015.05.038.