phenomenon · claim-type · cross-domain-transfer · mechanism · claim-relation · replication-status · limitation — grounded in the full text| phenomenon | delay activity in working memory— “Working memory is characterized by neural activity that persists during the retention interval of delay tasks.” | |
| claim-type | critique— “First, although delay activity has classically been described as sustained activation of highly tuned neurons or neural populations, the abundance of evidence for time-varying forms of delay activity and population coding indicates that a broader view of delay activity is necessary.” | |
| method — evidence | — “This Review integrates findings across subfields of neuroscience to critically evaluate the what, where and how of delay activity.” | |
| object of study — evidence | — “Working memory is characterized by neural activity that persists during the retention interval of delay tasks. Despite the ubiquity of this ‘delay activity’ across tasks, species and experimental techniques, our understanding of this phenomenon remains incomplete. Although initially there was a narrow focus on sustained activation in a small… | |
| research question — evidence | — “Although initially there was a narrow focus on sustained activation in a small number of brain regions, methodological and analytical advances have allowed researchers to uncover previously unobserved forms of delay activity across the entire brain.” | |
| contribution — evidence | — “discussions of delay activity that typically focus on increases in spike rate or functional MRI (fMRI) signal that persist throughout a WM delay, we consider delay activity to be any task-related change in neural activity that spans the interval between a stimulus and the behavioural response in a WM delay task . This expanded definition… | |
| mechanism | Structured recurrent excitation with tuned excitation–inhibition balance lets network spiking settle into a self-sustaining attractor state that keeps the memory alive without input— “When the connectivity between neurons in the network is properly structured, and when the balance between excitation and inhibition is well-tuned, spiking dynamics settle into a stable attractor state in the absence of any input” | mechanisms[0] |
| mechanism | Slow NMDA-receptor excitation stabilises attractor networks so that persistent spiking can be maintained over seconds— “The relatively slow excitatory dynamics of NMDAR activation can provide a stabilizing influence on attractor networks, allowing these networks to sustain a representation through persistent spiking over several seconds” | mechanisms[1] |
| mechanism | Encoding-driven changes in synaptic weights turn the network into a matched filter, so the memory is stored silently and revealed when noisy input is fed through it— “According to activity silent models, shifts in synaptic weights during stimulus encoding cause the network to act as a matched filter” | mechanisms[2] |
| mechanism | Feedforward connections between similarly tuned cells relay brief bursts of spiking along a chain, storing information without any single cell firing continuously— “This connectivity enables the network to store information through brief periods of above-baseline spiking that are passed between cells” | mechanisms[3] |
| mechanism | Long-range input (from thalamus) is required for local cortical circuits to sustain delay activity at all— “local circuit mechanisms, which have long been implicated in delay activity, may be insufficient to sustain delay activity in the absence of long-range input” | mechanisms[4] |
| mechanism | the definition is widened deliberately and its price is named in the same sentence: THIS EXPANDED DEFINITION ALLOWS FOR A MORE INCLUSIVE AND COMPREHENSIVE EVALUATION OF DELAY ACTIVITY, BUT AT THE SAME TIME CALLS ATTENTION TO THE CHALLENGE OF COMPARING DATA ACROSS DIFFERENT EXPERIMENTAL METHODS, BRAIN REGIONS AND SPECIES— “discussions of delay activity that typically focus on increases in spike rate or functional MRI (fMRI) signal that persist throughout a WM delay, we consider delay activity to be any task-related change in neural activity that spans the interval between a stimulus and the behavioural response in a WM delay task . This expanded definition… | mechanisms[5] |
| mechanism | and the one design that escapes the problem: WE ADDRESS THIS ISSUE BY HIGHLIGHTING STUDIES THAT RECORD DELAY ACTIVITY ACROSS MULTIPLE BRAIN REGIONS IN THE SAME EXPERIMENT— “We address this issue by highlighting studies that record delay activity across multiple brain regions in the same experiment. Second, we emphasize points of connection between empirical studies and neural models of delay activity.” | mechanisms[6] |
| mechanism | a code that cannot be read from its parts: THE PROPERTY OF NONLINEAR MIXED SELECTIVITY ENABLES INDIVIDUAL NEURONS TO RESPOND TO COMBINATIONS OF TASK AND STIMULUS FEATURES SUCH THAT FEATURE COMBINATIONS CANNOT BE READ OUT FROM THE RESPONSES OF THE INDIVIDUAL NEURON ALONE AND INSTEAD ARE ENCODED IN THE COMBINED ACTIVITY OF SEVERAL NEURONS— “The property of nonlinear mixed selectivity enables individual neurons to respond to combinations of task and stimulus features such that feature combinations cannot be read out from the responses of the individual neuron alone 124 and instead are encoded in the combined activity of several neurons” | mechanisms[7] |
| critiques | the narrow definition of delay activity as sustained spike-rate or fMRI increase— “discussions of delay activity that typically focus on increases in spike rate or functional MRI (fMRI) signal that persist throughout a WM delay, we consider delay activity to be any task-related change in neural activity that spans the interval between a stimulus and the behavioural response in a WM delay task . This expanded definition… | claim_relations[0] |
| reconciles | the positions that lPFC delay activity codes content and that it codes goals— “reconcile these perspectives have given rise to a more nuanced view: that lPFC delay activity simultaneously represents multiple dimensions of WM content and goals” | claim_relations[1] |
| qualifies | the classic sustained-enhancement description of delay activity— “Moreover, the frequency of gamma bursts also increased when the monkey accessed WM information to compare a memory item with a visually presented probe 42 . Only after averaging activity over trials did the classic patterns of sustained gamma and beta enhancement emerge.” | claim_relations[2] |
| reconciles | the positions that lPFC delay activity codes content and that it codes goals— “reconcile these perspectives have given rise to a more nuanced view: that lPFC delay activity simultaneously represents multiple dimensions of WM content and goals” | claim_relations[3] |
| sense | THE DEFINITION IS WIDENED IN THE SECOND PARAGRAPH, AND THE COST IS IN THE SAME SENTENCE: WE CONSIDER DELAY ACTIVITY TO BE ANY TASK-RELATED CHANGE IN NEURAL ACTIVITY THAT SPANS THE INTERVAL BETWEEN A STIMULUS AND THE BEHAVIOURAL RESPONSE IN A WM DELAY TASK - THIS EXPANDED DEFINITION ALLOWS FOR A MORE INCLUSIVE AND COMPREHENSIVE EVALUATION OF DELAY ACTIVITY, BUT AT THE SAME TIME CALLS ATTENTION TO THE CHALLENGE OF COMPARING DATA ACROSS DIFFERENT EXPERIMENTAL METHODS, BRAIN REGIONS AND SPECIES— “discussions of delay activity that typically focus on increases in spike rate or functional MRI (fMRI) signal that persist throughout a WM delay, we consider delay activity to be any task-related change in neural activity that spans the interval between a stimulus and the behavioural response in a WM delay task . This expanded definition… | senses[0] |
| sense | and what it replaces is named: DISCUSSIONS OF DELAY ACTIVITY THAT TYPICALLY FOCUS ON INCREASES IN SPIKE RATE OR FUNCTIONAL MRI (fMRI) SIGNAL THAT PERSIST THROUGHOUT A WM DELAY. The older definition is a MEASUREMENT; the new one is a RELATION to the task— “discussions of delay activity that typically focus on increases in spike rate or functional MRI (fMRI) signal that persist throughout a WM delay, we consider delay activity to be any task-related change in neural activity that spans the interval between a stimulus and the behavioural response in a WM delay task . This expanded definition… | senses[1] |
| sense | THE PHENOMENON GREW WHEN THE INSTRUMENTS CHANGED: ALTHOUGH INITIALLY THERE WAS A NARROW FOCUS ON SUSTAINED ACTIVATION IN A SMALL NUMBER OF BRAIN REGIONS, METHODOLOGICAL AND ANALYTICAL ADVANCES HAVE ALLOWED RESEARCHERS TO UNCOVER PREVIOUSLY UNOBSERVED FORMS OF DELAY ACTIVITY ACROSS THE ENTIRE BRAIN— “Although initially there was a narrow focus on sustained activation in a small number of brain regions, methodological and analytical advances have allowed researchers to uncover previously unobserved forms of delay activity across the entire brain.” | senses[2] |
| sense | and each instrument sees a different thing: RECORDING DELAY ACTIVITY AT THESE DIFFERENT SCALES REQUIRES MULTIPLE TECHNIQUES, EACH OF WHICH IS SENSITIVE TO DIFFERENT ASPECTS OF THE UNDERLYING NEURONAL SIGNALS— “Delay activity can be observed in many forms at various scales — from individual neurons, to cell assemblies comprised of tens of neurons, meso-scale interregional circuits or macro-level networks that recruit regions throughout the brain. Recording delay activity at these different scales requires multiple techniques, each of which is… | senses[3] |
| sense | THE CLASSIC RESULT IS A PRODUCT OF THE AVERAGE: ONLY AFTER AVERAGING ACTIVITY OVER TRIALS DID THE CLASSIC PATTERNS OF SUSTAINED GAMMA AND BETA ENHANCEMENT EMERGE. The sustained pattern that named the phenomenon is not present in any single trial— “Moreover, the frequency of gamma bursts also increased when the monkey accessed WM information to compare a memory item with a visually presented probe 42 . Only after averaging activity over trials did the classic patterns of sustained gamma and beta enhancement emerge.” | senses[4] |
| sense | and the underlying signal is disputed: SOME HAVE ARGUED AGAINST THIS INTERPRETATION OF LFP BURST DATA, SUGGESTING THAT GAMMA BURSTS MAY ACTUALLY REFLECT SPIKING— “Some have argued against this interpretation of LFP burst data, suggesting that gamma bursts may actually reflect spiking” | senses[5] |
| sense | THE OBSTACLE IS THE SAME THREE THINGS EVERY TIME: DIFFERENCES IN TASKS, METHODOLOGY AND SPECIES IN THE ABOVE STUDIES POSE A SIGNIFICANT OBSTACLE TO UNCOVERING THE LOCATION AND FUNCTION OF DELAY ACTIVITY— “Differences in tasks, methodology and species in the above studies pose a significant obstacle to uncovering the location and function of delay activity. Here we consider studies that directly compare delay activity across regions.” | senses[6] |
| sense | and the only clean design is named: WE ADDRESS THIS ISSUE BY HIGHLIGHTING STUDIES THAT RECORD DELAY ACTIVITY ACROSS MULTIPLE BRAIN REGIONS IN THE SAME EXPERIMENT - compare within one experiment, because between experiments the comparison is not available— “We address this issue by highlighting studies that record delay activity across multiple brain regions in the same experiment. Second, we emphasize points of connection between empirical studies and neural models of delay activity.” | senses[7] |
| sense | A CODE THAT CANNOT BE READ FROM ITS PARTS: NONLINEAR MIXED SELECTIVITY ENABLES INDIVIDUAL NEURONS TO RESPOND TO COMBINATIONS OF TASK AND STIMULUS FEATURES SUCH THAT FEATURE COMBINATIONS CANNOT BE READ OUT FROM THE RESPONSES OF THE INDIVIDUAL NEURON ALONE AND INSTEAD ARE ENCODED IN THE COMBINED ACTIVITY OF SEVERAL NEURONS. A per-neuron tag cannot carry what the population encodes— “The property of nonlinear mixed selectivity enables individual neurons to respond to combinations of task and stimulus features such that feature combinations cannot be read out from the responses of the individual neuron alone 124 and instead are encoded in the combined activity of several neurons” | senses[8] |
| sense | and it is offered as a reconciliation of two positions: ATTEMPTS TO RECONCILE THESE PERSPECTIVES HAVE GIVEN RISE TO A MORE NUANCED VIEW, THAT lPFC DELAY ACTIVITY SIMULTANEOUSLY REPRESENTS MULTIPLE DIMENSIONS OF WM CONTENT AND GOALS | senses[9] |
| sense | AND FOR ONE INSTRUMENT THE SOURCE OF THE SIGNAL IS UNKNOWN: CHALLENGES IN LOCALIZING EEG ACTIVITY MAKE IT UNCLEAR WHERE IN THE BRAIN THESE SIGNALS ORIGINATE - so a `where` claim from that instrument is not a claim about a place | senses[10] |
| sense | the review's own framing of what it is doing: IN LIGHT OF THESE NEW FINDINGS, THIS REVIEW RECONSIDERS WHAT DELAY ACTIVITY IS, WHERE IN THE BRAIN IT IS FOUND, WHAT ROLES IT SERVES AND HOW IT MAY BE GENERATED | senses[11] |
| sense | and it is offered as a reconciliation of two positions: ATTEMPTS TO RECONCILE THESE PERSPECTIVES HAVE GIVEN RISE TO A MORE NUANCED VIEW, THAT lPFC DELAY ACTIVITY SIMULTANEOUSLY REPRESENTS MULTIPLE DIMENSIONS OF WM CONTENT AND GOALS 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[12] |
| sense | AND FOR ONE INSTRUMENT THE SOURCE OF THE SIGNAL IS UNKNOWN: CHALLENGES IN LOCALIZING EEG ACTIVITY MAKE IT UNCLEAR WHERE IN THE BRAIN THESE SIGNALS ORIGINATE - so a `where` claim from that instrument is not a claim about a place 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[13] |
| control | the review restricted, where possible, to experiments that record several regions at once — partial — rules out differences between studies masquerading as differences between regions - WE ADDRESS THIS ISSUE BY HIGHLIGHTING STUDIES THAT RECORD DELAY ACTIVITY ACROSS MULTIPLE BRAIN REGIONS IN THE SAME EXPERIMENT 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] |
| differs in | the narrow definition of delay activity as sustained spike-rate or fMRI increase — what counts as delay activity - ANY TASK-RELATED CHANGE IN NEURAL ACTIVITY THAT SPANS THE INTERVAL BETWEEN A STIMULUS AND THE BEHAVIOURAL RESPONSE 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] |
| differs in | the positions that lPFC delay activity codes content and that it codes goals — the assumption that a neuron codes one thing - NONLINEAR MIXED SELECTIVITY ENABLES INDIVIDUAL NEURONS TO RESPOND TO COMBINATIONS OF TASK AND STIMULUS FEATURES 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. 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] |
| differs in | the classic sustained-enhancement description of delay activity — whether trials are averaged - ONLY AFTER AVERAGING ACTIVITY OVER TRIALS DID THE CLASSIC PATTERNS OF SUSTAINED GAMMA AND BETA ENHANCEMENT EMERGE 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] |
| differs in | the positions that lPFC delay activity codes content and that it codes goals — the assumption that a neuron codes one thing - NONLINEAR MIXED SELECTIVITY ENABLES INDIVIDUAL NEURONS TO RESPOND TO COMBINATIONS OF TASK AND STIMULUS FEATURES 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. 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] |
| audit | delay activity —part-of→ WM — Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but delay activity is defined as activity spanning a WM delay; part-of is loose. 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] |
| depends on | delay activity —part-of→ WM — which definition is in force - the older one focuses on INCREASES IN SPIKE RATE OR FUNCTIONAL MRI (fMRI) SIGNAL THAT PERSIST THROUGHOUT A WM DELAY 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] |
| note | delay activity —part-of→ WM — ANY TASK-RELATED CHANGE IN NEURAL ACTIVITY THAT SPANS THE INTERVAL BETWEEN A STIMULUS AND THE BEHAVIOURAL RESPONSE IN A WM DELAY 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. | concept_edges[0] |
| audit | delay activity —operationalised-as→ fMRI — Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but the paper widens delay activity BEYOND spike-rate and fMRI increases; operationalised-as fMRI is loose. 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 | delay activity —operationalised-as→ fMRI — the definition being replaced: DISCUSSIONS OF DELAY ACTIVITY THAT TYPICALLY FOCUS ON INCREASES IN SPIKE RATE OR FUNCTIONAL MRI (fMRI) SIGNAL THAT PERSIST THROUGHOUT A WM DELAY 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] |
| weight | delay activity —operationalised-as→ fMRI — 0.5 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] |
| audit | gamma —contrasted-with→ beta — Audit 2026-09-28: DOUBTFUL - read against its span and kept, but the span reports gamma bursts; the beta contrast is not in the shown text. 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[7] |
| note | gamma —contrasted-with→ beta — beta bursts SEEMED TO INHIBIT GAMMA BURSTS AND REDUCED THE INFORMATION CONTENT OF SPIKING ACTIVITY 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[7] |
| outcome (stated by the tagger, no quotation) | control — partial | controls[0] |
| for which use | limitation — the attribution of delay activity to working memory: DELAY ACTIVITY IS SEEN MORE GENERALLY IN CONTEXTS THAT REQUIRE AN ORGANISM TO LINK A SENSORY STIMULUS TO A DELAYED BEHAVIOUR, SUCH AS DURING TASKS OF SUSTAINED ATTENTION OR DECISION MAKING 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 comparison the review makes under its own definition: it ALLOWS FOR A MORE INCLUSIVE AND COMPREHENSIVE EVALUATION ... BUT AT THE SAME TIME CALLS ATTENTION TO THE CHALLENGE OF COMPARING DATA ACROSS DIFFERENT EXPERIMENTAL METHODS, BRAIN REGIONS AND SPECIES 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 coverage of the biophysical modelling literature: AS THE RELATIONSHIP BETWEEN THE BIOPHYSICAL PROPERTIES OF NEURONS OR MICRO-SCALE NETWORKS AND THE EFP OR BOLD SIGNALS IS INCOMPLETELY UNDERSTOOD, BIOPHYSICAL MODELS ALMOST EXCLUSIVELY ATTEMPT TO DESCRIBE SPIKING 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 — pooling delay-activity findings across techniques without asking what each technique can see 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 localisation and function questions the review is asking: DIFFERENCES IN TASKS, METHODOLOGY AND SPECIES IN THE ABOVE STUDIES POSE A SIGNIFICANT OBSTACLE TO UNCOVERING THE LOCATION AND FUNCTION OF DELAY ACTIVITY 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 — treating a delay signal recorded one way as the same object as one recorded another way 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 EEG evidence specifically: CHALLENGES IN LOCALIZING EEG ACTIVITY MAKE IT UNCLEAR WHERE IN THE BRAIN THESE SIGNALS ORIGINATE 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 LFP burst evidence: SOME HAVE ARGUED AGAINST THIS INTERPRETATION OF LFP BURST DATA, SUGGESTING THAT GAMMA BURSTS MAY ACTUALLY REFLECT SPIKING 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] |
| replication | untested | |
| limitation | DELAY ACTIVITY IS SEEN MORE GENERALLY IN CONTEXTS THAT REQUIRE AN ORGANISM TO LINK A SENSORY STIMULUS TO A DELAYED BEHAVIOUR, SUCH AS DURING TASKS OF SUSTAINED ATTENTION OR DECISION MAKING; HERE, HOWEVER, WE EXAMINE DELAY ACTIVITY IN TASKS EXPLICITLY TESTING WM, WHERE IT HAS BEEN CHARACTERIZED MOST EXTENSIVELY 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 | The broad definition the review adopts makes comparison across methods, regions and species harder. 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 | AS THE RELATIONSHIP BETWEEN THE BIOPHYSICAL PROPERTIES OF NEURONS OR MICRO-SCALE NETWORKS AND THE EFP OR BOLD SIGNALS IS INCOMPLETELY UNDERSTOOD, BIOPHYSICAL MODELS ALMOST EXCLUSIVELY ATTEMPT TO DESCRIBE SPIKING ACTIVITY; ACCORDINGLY, WE FOCUS OUR DISCUSSION HERE ON DELAY SPIKING 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 | the expanded definition makes the literature harder to compare, not easier - THE CHALLENGE OF COMPARING DATA ACROSS DIFFERENT EXPERIMENTAL METHODS, BRAIN REGIONS AND SPECIES 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 | DIFFERENCES IN TASKS, METHODOLOGY AND SPECIES IN THE ABOVE STUDIES POSE A SIGNIFICANT OBSTACLE TO UNCOVERING THE LOCATION AND FUNCTION OF DELAY ACTIVITY 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 | each instrument sees a different thing - RECORDING DELAY ACTIVITY AT THESE DIFFERENT SCALES REQUIRES MULTIPLE TECHNIQUES, EACH OF WHICH IS SENSITIVE TO DIFFERENT ASPECTS OF THE UNDERLYING NEURONAL SIGNALS 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 | and for one of those instruments the source is unknown - CHALLENGES IN LOCALIZING EEG ACTIVITY MAKE IT UNCLEAR WHERE IN THE BRAIN THESE SIGNALS ORIGINATE 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 | the interpretation of the burst data is contested - SOME HAVE ARGUED AGAINST THIS INTERPRETATION OF LFP BURST DATA, SUGGESTING THAT GAMMA BURSTS MAY ACTUALLY REFLECT SPIKING 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 | and for one of those instruments the source is unknown - CHALLENGES IN LOCALIZING EEG ACTIVITY MAKE IT UNCLEAR WHERE IN THE BRAIN THESE SIGNALS ORIGINATE 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] |
finding · quantity · variable · definition · key-term — grounded in the full text| finding | One lateral prefrontal study estimated that only 3% of delay-active neurons spike at a stable rate throughout the delay. 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 | GAMMA BURSTS WERE ASSOCIATED WITH INCREASED INFORMATION OR MORE ITEMS STORED IN WM, WHEREAS BETA BURSTS SEEMED TO INHIBIT GAMMA BURSTS AND REDUCED THE INFORMATION CONTENT OF SPIKING ACTIVITY 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 | Optogenetically inhibiting thalamic delay activity disrupted delay activity in frontal regions. 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 | Thalamic delay activity is not a copy of the cortical signal — it is less content-selective than frontal delay activity yet causally sets frontal 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[3] |
| finding | POPULATION ANALYSES OF fMRI DATA HAVE REVEALED SUSTAINED REPRESENTATIONS OF WM CONTENT IN THE PATTERN OF ACTIVITY OF VOXELS DISTRIBUTED WITHIN PARIETAL AND SENSORY CORTICES, EVEN WHEN THE MEAN BOLD SIGNAL DOES NOT DIFFER FROM BASELINE ACROSS THE DELAY 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 | Which region shows delay activity depends on the animal's strategy: a prospective motor strategy raised prefrontal delay activity while a retrospective sensory strategy raised it in posterior 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. | content_tags.findings[5] |
| finding | In monkey lPFC, drift in population delay spiking predicted the size of the behavioural error. 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 | Blocking prefrontal NMDA receptors eliminates delay spiking in non-human primates. 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 | No single biophysical model reproduces every property of delay activity, and most empirical results are equally compatible with several model classes. 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 | WE CONSIDER DELAY ACTIVITY TO BE ANY TASK-RELATED CHANGE IN NEURAL ACTIVITY THAT SPANS THE INTERVAL BETWEEN A STIMULUS AND THE BEHAVIOURAL RESPONSE IN A WM DELAY 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. | content_tags.findings[9] |
| finding | THIS EXPANDED DEFINITION ALLOWS FOR A MORE INCLUSIVE AND COMPREHENSIVE EVALUATION OF DELAY ACTIVITY, BUT AT THE SAME TIME CALLS ATTENTION TO THE CHALLENGE OF COMPARING DATA ACROSS DIFFERENT EXPERIMENTAL METHODS, BRAIN REGIONS AND SPECIES 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 | METHODOLOGICAL AND ANALYTICAL ADVANCES HAVE ALLOWED RESEARCHERS TO UNCOVER PREVIOUSLY UNOBSERVED FORMS OF DELAY ACTIVITY ACROSS THE ENTIRE BRAIN 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 | ONLY AFTER AVERAGING ACTIVITY OVER TRIALS DID THE CLASSIC PATTERNS OF SUSTAINED GAMMA AND BETA ENHANCEMENT EMERGE 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 | DIFFERENCES IN TASKS, METHODOLOGY AND SPECIES IN THE ABOVE STUDIES POSE A SIGNIFICANT OBSTACLE TO UNCOVERING THE LOCATION AND FUNCTION OF DELAY ACTIVITY 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 | FEATURE COMBINATIONS CANNOT BE READ OUT FROM THE RESPONSES OF THE INDIVIDUAL NEURON ALONE AND INSTEAD ARE ENCODED IN THE COMBINED ACTIVITY OF SEVERAL NEURONS 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 | CHALLENGES IN LOCALIZING EEG ACTIVITY MAKE IT UNCLEAR WHERE IN THE BRAIN THESE SIGNALS ORIGINATE 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] |
| finding | SOME HAVE ARGUED AGAINST THIS INTERPRETATION OF LFP BURST DATA, SUGGESTING THAT GAMMA BURSTS MAY ACTUALLY REFLECT SPIKING 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[16] |
| quantity | 3% — Proportion of delay-active lateral prefrontal neurons that fire at a stable rate through the whole delay 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 | 40–100 Hz — Frequency range the review assigns to the gamma band whose power is sustained during working-memory delays 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 | 42 — Number of cortical areas recorded simultaneously in the broadest-coverage monkey study of content-selective delay spiking 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 | ~100,000 — Number of voxels in a 3D fMRI brain image, each pooling tens of thousands of neurons 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 | 10–15 s — Typical fixed delay length used in the most common fMRI boxcar design for estimating delay activity 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] |
| variable | delay activity 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[0] |
| definition | delay spiking 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 | population coding 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 | bistability 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 | activity silent models 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 | nonlinear 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[5] |
| definition | sensory recruitment model 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 | delay activity 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] |
| 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[8] |
| key-terms | delay activity, WM, lPFC, technique, scale, species, task, region, averaging, burst, gamma, beta, mixed selectivity, EEG, fMRI |
| claim type | critique — a second reading reaching the same value; recorded: critique 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 | review across scales and techniques, giving weight to studies that record in multiple regions within one experiment because that is the only way to compare — a second reading DIFFERING from the recorded value; recorded: review 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 | a fifty-year-old phenomenon whose extent grew when the instruments changed, not when the brain did — a second reading DIFFERING from the recorded value; recorded: delay activity in working 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. | alternatives.phenomenon |
When we have changed our mind. Some entries in the table begin with a word in capitals and the reason for it. EVIDENCE CORRECTED — the finding still stands, but we had quoted the wrong sentence from the paper, and the quotation has been replaced with the right one. RETRACTED — the entry itself was wrong; it stays on the page, marked, with the reason, rather than being deleted. WITHDRAWN AND REPLACED — the entry was wrong, and a corrected version of it appears in the entries below. Each mark carries its own reason, in brackets, because the reasons differ from one entry to the next. An entry we have WITHDRAWN is removed from this page and kept in the record, with its reason. A line reading Audit and a date is a later re-reading of the entry against its whole sentence: DOUBTFUL means it was kept, and the reason says what is loose about it. Quotation marks inside the tagger's sentence. Where a tag is the tagger's own sentence, a phrase in quotation marks inside it is borrowed from the paper — the tagger's wording around it is not. The paper's own sentence is the evidence quote for that row; on this page it is withheld with the article, and the article is at its publisher. Nothing inside quotation marks anywhere on this page is ours: if it is quoted, it is the paper's. Whose words a concept carries. A concept entry records a term the paper itself uses, so the term, the sense given for it, and its evidence are the paper's own words, quoted where the paper fixes them. This is the opposite of a sense entry in the tag table, which is the tagger's sentence about how the paper uses a term. Where a concept entry could not be grounded in the paper's words, the entry says so on its own row.
Tag layer © the Meta-Tagging Project, CC BY 4.0. The paper text is © its authors/publisher
and is linked, not reproduced. Excerpts shown are short quotations for identification and verification.
· back to index
· concepts · authors
· עברית
© 2026 Shir Sivroni · ORCID 0009-0000-2597-2824