phenomenon · claim-type · cross-domain-transfer · mechanism · claim-relation · replication-status · limitation — grounded in the full text| phenomenon | mixed selectivity in prefrontal cortex— “Single-neuron activity in prefrontal cortex (PFC) is tuned to mixtures of multiple task-related aspects.” | |
| claim-type | mechanism— “This advantage originates from the highly diverse non-linear selectivity to mixtures of task-relevant variables, a signature of high-dimensional neural representations.” | |
| method — evidence | — “We analysed the activity of 237 lateral PFC neurons (area 46) recorded in two monkeys during the trial epochs that precede and include the two-object delay period.” | |
| object of study — evidence | — “Single-neuron activity in prefrontal cortex (PFC) is tuned to mixtures of multiple task-related aspects. Such mixed selectivity is highly heterogeneous, seemingly disordered and therefore difficult to interpret.” | |
| research question — evidence | — “The predominance of these mixed selectivity neurons appears to be a hallmark of PFC and other brain structures involved in cognition. Understanding such neural representations has been a major conceptual challenge in the field.” | |
| contribution — evidence | — “Specifically we found that: 1) the populations of recorded neurons encode distributed information that is not contained in classical selectivity to individual task aspects, 2) the recorded neural representations are high-dimensional, and 3) the dimensionality of the recorded neural representations predicts behavioural performance.” | |
| transfer | from machine learning: the analysis of the recorded population was designed from machine-learning theory about how learning principles operate in neuronal circuits— “Motivated by recent theoretical advances in understanding how machine learning principles play out in the functioning of neuronal circuits” | transfers[0] |
| transfer | from machine learning: the coding strategy of support vector machines is used as the interpretive frame for what mixed selectivity is doing— “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” | transfers[1] |
| transfer | from machine learning: the perceptron learning rule is imported as the supervised procedure by which a readout neuron's weights would be adjusted— “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 ]).” | transfers[2] |
| transfer | from machine learning: the kernel-machine insight that projecting into a high-dimensional space lets a linear classifier implement more functions, imported as the interpretation of PFC tuning— “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 high-dimensional neural… | transfers[3] |
| transfer | from statistical learning theory: counting implementable dichotomies as a measure of representational capacity, used here as the dimensionality estimator— “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 estimated by counting the number… | transfers[4] |
| transfer | from premotor cortex physiology: the observation that firing rates are less variable on faster-reaction-time trials, used as the analogy for variability driving the error-trial collapse— “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.” | transfers[5] |
| mechanism | on error trials the non-linear mixed selectivity component is disrupted, dimensionality collapses, and downstream readout neurons can no longer be driven to the correct output— “In the error trials this component of the selectivity is disrupted, leading to a collapse in dimensionality, which impairs the ability of downstream readout neurons to produce the correct response.” | mechanisms[0] |
| mechanism | excessive variability from sources that are not task-relevant enters the non-linear mixing and changes the dimensionality— “The change in dimensionality may be caused by the excessive variability of sources that are not task-relevant.” | mechanisms[1] |
| mechanism | diverse non-linear selectivity to mixtures of task variables raises the dimension of the representation, which is what gives linear readouts their expanded repertoire of input-output functions— “This advantage originates from the highly diverse non-linear selectivity to mixtures of task-relevant variables, a signature of high-dimensional neural representations.” | mechanisms[2] |
| mechanism | strongly non-linear mixed selectivity neurons are more sensitive to task-irrelevant variability, which is why the most useful component of the code is also the most fragile— “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.” | mechanisms[3] |
| mechanism | dimensionality is estimated by counting how many binary classifications a linear classifier can implement, since that number grows exponentially with dimension— “Our method relies on the observation that the number of binary classifications that can be implemented by a linear classifier grows… | mechanisms[4] |
| mechanism | the estimate is converted by d = log2(Nc), valid when the number of inputs is large enough | mechanisms[5] |
| mechanism | only non-linear mixed selectivity can raise dimensionality: pure selectivity and linear mixing generate low-dimensional representations Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | mechanisms[6] |
| mechanism | classical selectivity is removed by adding noise that equalises average responses while preserving differences between individual conditions Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | mechanisms[7] |
| mechanism | averaging over conditions to test classical selectivity is itself what discards the distributed information Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | mechanisms[8] |
| mechanism | the proposed cause of the error-trial collapse: non-linear mixing is more sensitive than pure selectivity to task-irrelevant variability, so it is the most useful and the most fragile component Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | mechanisms[9] |
| mechanism | non-simultaneously recorded neurons are combined into pseudo-simultaneous population vectors, discarding temporal correlations Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | mechanisms[10] |
| builds-on | the monkey object sequence memory dataset of ref [3] Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | claim_relations[0] |
| builds-on | machine-learning-inspired circuit theory, refs [4]-[10] Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | claim_relations[1] |
| extends | prior linear-readout decoding studies, refs [17], [18] Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | claim_relations[2] |
| reinterprets | the heterogeneous, seemingly disordered tuning that reverse-engineering approaches treat as noise Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | claim_relations[3] |
| extends | previous demonstrations that a linear readout suffices to decode particular task aspects Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | claim_relations[4] |
| supports | model circuits that expand dimensionality by random non-linear mixing Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | claim_relations[5] |
| qualifies | its own claim, by allowing that dendritic non-linearities could hide the expansion Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | claim_relations[6] |
| contradicts | the grandmother-cell account of how high dimensionality could arise Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | claim_relations[7] |
| sense | dimensionality here is a property of CONDITION space: the minimal number of coordinate axes needed to place one firing-rate vector per experimental condition. It is not a statement about time courses across cells Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | senses[0] |
| sense | high-dimensional is therefore a bounded claim in this paper - the ceiling is the number of conditions, here 24, and the data reach it Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | senses[1] |
| sense | mixed selectivity means tuning to a mixture of task aspects; only the NON-LINEAR kind raises dimensionality, and the paper keeps linear and non-linear mixing strictly apart Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | senses[2] |
| sense | classically selective is defined by a significant difference in averages across a task aspect - and the paper's point is that this test discards the information it is looking for Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | senses[3] |
| sense | pure selectivity means responding to one aspect at a time; it is the foil, simulated rather than recorded Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | senses[4] |
| control | the decoder's performance was checked against the possibility that it had saturated — held — rules out that the correspondence between dimensionality and performance is a ceiling effect of the population decoder rather than a property of the representation Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | controls[0] |
| note | non-linear mixed selectivity —causes→ dimensionality — and the same quote carries the negative half: pure and linear mixed selectivity can only generate low-dimensional representations Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concept_edges[0] |
| weight | non-linear mixed selectivity —causes→ dimensionality — 0.95 Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concept_edges[0] |
| edge | linear mixed selectivity —contrasted-with→ non-linear mixed selectivity Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concept_edges[1] |
| note | dimensionality —operationalised-as→ binary classifications — an abstract property measured through a downstream tool's capacity - d = log2(Nc) Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concept_edges[2] |
| outcome (stated by the tagger, no quotation) | control — held | controls[0] |
| for which use | limitation — the error analysis, which exists only for the recall task: WE TESTED THIS PREDICTION BY ANALYSING THE ERRORS MADE BY THE MONKEYS IN THE RECALL TASK (THERE WERE TOO FEW ERRORS IN THE RECOGNITION TASK) Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[0] |
| for which use | limitation — every population-level correlation and dimensionality claim: NEURONS THAT WERE NOT RECORDED SIMULTANEOUSLY WERE COMBINED AS PSEUDO-SIMULTANEOUS POPULATION ACTIVITY PATTERNS Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[1] |
| for which use | limitation — the argument as stated, which assumes linear readouts: IT IS LEGITIMATE TO ASK WHETHER THESE CONSIDERATIONS WOULD STILL BE VALID IF WE CONSIDER MORE COMPLEX NON-LINEAR READOUTS Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[2] |
| for which use | limitation — any claim that dimensionality expansion happens at the population level rather than within cells: OUR RESULTS DO NOT EXCLUDE THE FUNCTIONAL IMPORTANCE OF SUCH DENDRITIC PROCESSES Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[3] |
| for which use | limitation — the dimensionality number itself: ACCORDINGLY, THE DIMENSIONALITY IS BOUNDED BY THE TOTAL NUMBER OF DISTINCT CONDITIONS c - it cannot exceed the experiment's design Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[4] |
| for which use | limitation — the dimensionality estimate and the indirect method used to get it: AS THIS IS NOTORIOUSLY DIFFICULT IN THE PRESENCE OF NOISE, WE ADOPTED A NOVEL STRATEGY THAT EXPLOITS THE RELATION BETWEEN DIMENSIONALITY AND THE PERFORMANCE of a linear classifier Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[5] |
| for which use | limitation — the same scope as limitations[2], with the mechanism: SOME OF THE TRANSFORMATIONS WHICH INCREASE THE DIMENSIONALITY of the representation could be implemented in dendrites and would not appear in firing rates Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[6] |
| for which use | limitation — the strength of the paper's own claim: ALTHOUGH HIGH DIMENSIONALITY IS NOT STRICTLY NECESSARY FOR GENERATING RICH DYNAMICS AND PERFORMING COMPLEX TASKS, IT IS KNOWN TO GREATLY SIMPLIFY THE DESIGN OF LOCAL NEURAL CIRCUITS Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[7] |
| for which use | limitation — the causal account of the collapse, labelled as speculation by the authors: IT IS TEMPTING TO SPECULATE ABOUT THE CAUSES OF THIS DIMENSIONALITY COLLAPSE Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[8] |
| for which use | limitation — every population-level result: NEURONS THAT WERE NOT RECORDED SIMULTANEOUSLY WERE COMBINED AS PSEUDO-SIMULTANEOUS POPULATION ACTIVITY PATTERNS, and THE TEMPORAL CORRELATIONS THAT WERE NEGLECTED are lost by that construction Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[9] |
| for which use | limitation — the error analyses only: THESE ANALYSES WERE CARRIED OUT ON A SUBSET DATASET OF 121 NEURONS THAT WERE RECORDED IN AS MANY CORRECT AS ERROR TRIALS DURING THE RECALL TASK Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[10] |
| evidential status | mechanism — the paper's own words: may be caused by Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | mechanisms[1] |
| replication | untested | |
| limitation | Errors could only be analysed in the recall task because the recognition task yielded too few of them. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[0] |
| limitation | Non-simultaneously recorded neurons were combined into pseudo-simultaneous population patterns, neglecting temporal correlations. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[1] |
| limitation | The argument is framed for linear readouts; whether it holds for more complex non-linear readouts is left open. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[2] |
| limitation | Dimensionality expansion by single-neuron dendritic non-linearities is not ruled out. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[3] |
| limitation | the measured dimensionality is bounded above by the number of experimental conditions, and the recorded data reach that maximum Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[4] |
| limitation | dimensionality is notoriously difficult to estimate in the presence of noise, which is why an indirect method was needed Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[5] |
| limitation | non-linear transformations implemented in dendrites could expand dimensionality invisibly, leaving firing-rate representations low-dimensional Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[6] |
| limitation | high dimensionality is not strictly necessary for rich dynamics or complex tasks; the claim is that it simplifies circuit design Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[7] |
| limitation | the causal account of the collapse is offered explicitly as speculation Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[8] |
| limitation | temporal correlations are discarded by the pseudo-simultaneous construction Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[9] |
| limitation | the error analysis rests on 121 neurons with enough error trials, and only in the recall task Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[10] |
finding · quantity · variable · definition · key-term — grounded in the full text| finding | Every task-relevant aspect can still be decoded from the PFC population after classical selectivity has been removed. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[0] |
| finding | During the two-object delay the recorded PFC population supports the maximum possible number of binary classifications, i.e. it attains the maximal dimensionality of 24 set by the 24 experimental conditions. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[1] |
| finding | Representations based on pure selectivity generate fewer than 8 dimensions. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[2] |
| finding | The dimensionality of the PFC representation drops on trials where the monkey makes an error, so dimensionality tracks behavioural success. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[3] |
| finding | On error trials the identities of the two cues could still be decoded with high accuracy. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[4] |
| finding | The dimensionality collapse that predicts the animal's errors is specifically due to a weakening of the non-linear component of mixed selectivity. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[5] |
| finding | The authors rule out grandmother-cell-like coding by verifying that PFC representations are rather dense. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[6] |
| finding | Removing classical selectivity costs the most decoding accuracy in the early epochs of the trial. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[7] |
| finding | every task-relevant aspect can still be decoded after classical selectivity to it has been removed from every neuron Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[8] |
| finding | the recovered accuracy grows as the task becomes more complex and more cues are held in memory Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[9] |
| finding | the recorded representations reach the maximal dimensionality allowed by the design, d = 24 Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[10] |
| finding | simulated pure-selectivity populations fall orders of magnitude short of the recorded ones Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[11] |
| finding | dimensionality collapses on error trials, as predicted before the test Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[12] |
| finding | cue identity is decoded just as well on error trials, so the collapse is not a failure to encode or remember the stimuli Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[13] |
| finding | the collapse is due specifically to the non-linear component of mixed selectivity Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[14] |
| finding | the dense, non-sparse character of the representations rules out a grandmother-cell explanation Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[15] |
| quantity | 237 — number of lateral PFC (area 46) neurons analysed, recorded in two monkeys Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[0] |
| quantity | 24 — number of distinct experimental conditions (combinations of cue 1, cue 2 and task type) Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[1] |
| quantity | less than 4% — difference between the number of correct and error trials for the 121 neurons used in the error analysis Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[2] |
| quantity | 100–150 trials — block length over which recognition and recall trials were interleaved Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[3] |
| quantity | p < 0.05 — significance of the difference between the two task types in an example neuron's response to object C as first cue Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[4] |
| quantity | close to 100% — maximal cross-validated decoding accuracy for all task-relevant aspects before selectivity removal Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[5] |
| quantity | 1000 — number of train/test partitions over which decoding accuracy was averaged, with 95% confidence intervals shown Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[6] |
| quantity | d = 12 — near-maximal dimensionality reached on correct recall-task trials Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[7] |
| quantity | 237 lateral PFC neurons (area 46) from two monkeys — the reanalysed sample Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[8] |
| quantity | 24 conditions, from 4 objects as cue 1, 3 remaining as cue 2, and 2 task types — the design that sets the ceiling on measurable dimensionality Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[9] |
| quantity | d = log2(Nc) — the conversion from implementable classifications to dimensionality Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[10] |
| quantity | 121 neurons with enough error trials, correct-error trial counts differing by less than 4% — the error-analysis subset Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[11] |
| quantity | blocks of 100 to 150 trials — the interleaving of recognition and recall Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[12] |
| variable | dimensionality of the neural representation (dependent) Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.variables[3] |
| variable | population decoding accuracy (dependent) Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.variables[4] |
| variable | noise level (control) Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.variables[5] |
| variable | task type Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.variables[6] |
| definition | mixed selectivity Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.definitions[0] |
| definition | dimensionality Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.definitions[1] |
| definition | non-linear mixed selectivity Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.definitions[2] |
| definition | classical selectivity Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.definitions[3] |
| definition | grandmother cell Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.definitions[4] |
| definition | dimensionality of a neural representation Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.definitions[5] |
| definition | mixed selectivity Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.definitions[6] |
| definition | classical selectivity Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.definitions[7] |
| key-terms | mixed selectivity, non-linear mixed selectivity, pure selectivity, dimensionality, prefrontal cortex, linear classifier, binary classifications, readout, support vector machines, grandmother cell, error trials, decoding, task-relevant aspects, classical selectivity, recall task, recognition, perceptron, random, delay period, population |
| t-test p | as written: two-sample t-test Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[0] |
| cross-validation | as written: estimated through cross-validation Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[1] |
| confidence interval | as written: 95% confidence bounds Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[2] |
| resampling | as written: resampling the recorded neurons and randomly relabelling the identities of the visual objects Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[3] |
| principal component analysis | as written: a principal component analysis Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[4] |
| standard error of the mean s.e.m | as written: shaded area indicates s.e.m Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[5] |
| cross-validated decoding accuracy | Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[6] |
| number of implementable binary classifications | Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[7] |
| claim type | mechanism — a second reading reaching the same value; recorded: mechanism Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | alternatives.claim_type |
| method | reanalysis of 237 lateral PFC neurons from two monkeys in a sequence memory task, with selectivity-removal manipulations and a dimensionality estimate from the number of implementable binary classifications — a second reading DIFFERING from the recorded value; recorded: electrophysiology Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | alternatives.method |
| phenomenon | high-dimensional population coding in prefrontal cortex — a second reading DIFFERING from the recorded value; recorded: mixed selectivity in prefrontal cortex Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | alternatives.phenomenon |
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