Local category-specific gamma band responses in the visual cortex do not reflect conscious perception

Local category-specific gamma band responses in the visual cortex do not reflect conscious perception Aru Axmacher Do Lam Fell Elger Singer Melloni

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Local category-specific gamma band responses in the visual cortex do not reflect conscious perception 2012 The Journal of Neuroscience: The Official Journal of the Society for Neuroscience 10.1523/jneurosci.2051-12.2012 Aru2012-local-category-specific-gamma-band-responses Aru2012-local-category-specific-gamma-band-responses.txt, the project's staged copy 5c4437329053910faf9421cfbd2a4f935a443afd not-redistributable neuroscience

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0 spans located by searching the stored text for the quote's exact words, allowing any whitespace between them whether category-specific gamma band responses in higher-order visual cortex are a direct neural correlate of conscious perception or a prerequisite for it Quotation withheld because this record is not cleared for redistribution. if local gamma band responses reflect conscious perception, do they follow it however it is brought about Quotation withheld because this record is not cleared for redistribution. shows that two manipulations which raise conscious perception equally are not equally reflected in gamma band responses — only sensory evidence is — and concludes local gamma is not the correlate of consciousness Quotation withheld because this record is not cleared for redistribution. null-result Quotation withheld because this record is not cleared for redistribution. neural correlates of conscious visual perception Quotation withheld because this record is not cleared for redistribution. electrophysiology electrophysiology Quotation withheld because this record is not cleared for redistribution. mechanisms Category-specific gamma indexes local sensory processing that is a necessary precondition for conscious perception rather than its direct correlate Quotation withheld because this record is not cleared for redistribution. mechanisms Stronger local preprocessing raises the probability that a stimulus reaches awareness, which manufactures a correlation between gamma and 'seen' reports without gamma causing awareness Quotation withheld because this record is not cleared for redistribution. mechanisms Differences in unconscious local processing propagate into different conscious outcomes, so local responses can correlate with awareness while being prerequisites of it Quotation withheld because this record is not cleared for redistribution. the criterion is invariance, not correlation: a correlate of consciousness must move whenever consciousness moves, whatever moved it Quotation withheld because this record is not cleared for redistribution. the disconfirmation rests on that invariance failing, which is why a single dissociation is enough to reject the proposal Quotation withheld because this record is not cleared for redistribution. two routes to the same behavioural endpoint are engineered — one that runs through local processing and one that does not — so the neural measure can be asked to choose Quotation withheld because this record is not cleared for redistribution. the equivalence of the two routes is established behaviourally first, across three separate samples, because the whole argument collapses if one manipulation is simply stronger Quotation withheld because this record is not cleared for redistribution. the null is defended by Monte Carlo power simulation rather than asserted, showing the test would have caught a 30% shift Quotation withheld because this record is not cleared for redistribution. the electrode selection contrast is chosen so that neither experimental factor can contaminate it — same degradation, neither group previously seen Quotation withheld because this record is not cleared for redistribution. the disputed study's own frequency band is analysed unchanged so the comparison is direct, and only then extended Quotation withheld because this record is not cleared for redistribution. catch trials containing only background give an independent check that the subjective report is trustworthy before it is used as the criterion Quotation withheld because this record is not cleared for redistribution. the rival explanation for the null — repetition suppression cancelling an enhancement — is closed with a boundary condition from the literature: repetition of degraded images enhances rather than suppresses Quotation withheld because this record is not cleared for redistribution. images are rotated through every condition across patients so no result can be an artefact of particular pictures Quotation withheld because this record is not cleared for redistribution. the within-subject reply to 'sensory evidence is just stronger' is that even patients for whom exposure mattered more behaviourally showed only the sensory effect neurally Quotation withheld because this record is not cleared for redistribution. Electrode coverage did not permit testing the alternative account, that long-range integration rather than local gamma tracks conscious perception. Quotation withheld because this record is not cleared for redistribution. Whether the two manipulations affect interareal integration in the same way is left open. Quotation withheld because this record is not cleared for redistribution. the alternative the paper favours — long-range integration — could not be tested with the electrodes available Quotation withheld because this record is not cleared for redistribution. whether the two manipulations affect interareal integration equally is unknown, so the positive account is untested duplicate of: limitations[1] Quotation withheld because this record is not cleared for redistribution. only one electrode showed a low-gamma effect surviving correction, so the low-band comparison with the disputed study rests on uncorrected effects Quotation withheld because this record is not cleared for redistribution. the frequency comparison with the disputed study is partly inference, since that study did not analyse above 70 Hz Quotation withheld because this record is not cleared for redistribution. full randomisation held for only four of the six patients Quotation withheld because this record is not cleared for redistribution. the integration account is left standing rather than supported, pending paradigms of this kind applied to it Quotation withheld because this record is not cleared for redistribution. Morlet wavelet convolution at roughly six cycles, used to resolve gamma power in time without committing to fixed epochs Quotation withheld because this record is not cleared for redistribution. Monte Carlo resampling used not to test the hypothesis but to establish that the reported null had the power to have found an effect Quotation withheld because this record is not cleared for redistribution. false discovery rate control applied across the full electrode-by-time grid, which is what lets the per-electrode table be read as a whole Quotation withheld because this record is not cleared for redistribution. the pictures containing a person were PSEUDORANDOMISED across four patients, so that each picture was assigned to every condition exactly once eliminates: picture-specific effects - any gamma-band response peculiar to one image is spread across all conditions instead of loading onto one, so it cannot be read as category selectivity · outcome (stated by the tagger, no quotation): held Quotation withheld because this record is not cleared for redistribution. neural correlate — as anything that covaries with report, versus as the process uniquely and directly associated with the experience; the paper's whole case turns on the second Quotation withheld because this record is not cleared for redistribution. gamma band response — low (30–70 Hz) versus high (70–150 Hz); the paper argues they are one broadband process seen more strongly at high frequencies Quotation withheld because this record is not cleared for redistribution. conscious perception — as the subjective report of seeing versus as the objective gender discrimination; both are collected and the analysis rests on the first Quotation withheld because this record is not cleared for redistribution. enhancing perception — by adding stimulus information versus by adding prior knowledge; behaviourally equivalent here, neurally not Quotation withheld because this record is not cleared for redistribution. consciousness arising locally in sensory cortices versus requiring integration across areas — the controversy the paper is intervening in Quotation withheld because this record is not cleared for redistribution. an effect that is corrected across electrodes and times versus one that is uncorrected; Table 1 reports both and the argument uses them differently Quotation withheld because this record is not cleared for redistribution. claim_type: null-result a second reading reaching the same value. Recorded: null-result — 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: intracranial EEG over occipital and temporal visual cortex while conscious perception is raised two independent ways — lower image degradation, and prior exposure to the clear image — with the two first shown behaviourally equivalent 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: conscious perception of a degraded image, and its dissociation from local category-specific cortical processing a second reading DIFFERING from the recorded value. Recorded: neural correlates of conscious visual perception — 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. contradicts → Fisch et al. (2009), the finding that local category-specific gamma band responses in visual cortex mark conscious perception Quotation withheld because this record is not cleared for redistribution. builds-on → Fisch et al. (2009) - electrode-selection procedure and analysed frequency range adopted for direct comparability Quotation withheld because this record is not cleared for redistribution. replicates → Fisch et al. (2009) - the contrastive seen-versus-unseen gamma band enhancement Quotation withheld because this record is not cleared for redistribution. builds-on → Aru et al. (2012) and de Graaf et al. (2012), the argument that standard NCC methods confound prerequisites and consequences of consciousness Quotation withheld because this record is not cleared for redistribution. contradicts → Fisch et al. (2009), that category-specific gamma in visual cortex correlates with and marks conscious perception Quotation withheld because this record is not cleared for redistribution. critiques → the contrastive method as used throughout consciousness research Quotation withheld because this record is not cleared for redistribution. supports → theories grounding consciousness in long-range integration rather than local processing depth Quotation withheld because this record is not cleared for redistribution. builds-on → Gray and Singer (1989), that stimulus-specific gamma persists under anesthesia Quotation withheld because this record is not cleared for redistribution. critiques → neuroimaging evidence for local accounts, as too slow to see the dynamics at issue Quotation withheld because this record is not cleared for redistribution. extends → the authors' own theoretical critique of NCC methodology (Aru et al., 2012), by turning it into an experiment Quotation withheld because this record is not cleared for redistribution. gamma band responses —distinct-from→ neural correlates of consciousness gamma band responses neural correlates of consciousness strength of the relation: 0.95 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but the span writes that gamma responses do not 'reflect conscious perception', not 'neural correlates of consciousness'; distinct-from is loose. Quotation withheld because this record is not cleared for redistribution. gamma band responses —is-a→ prerequisites gamma band responses prerequisites strength of the relation: 0.8 Audit 2026-09-28: DOUBTFUL - read against its span and kept, but the span calls local processing a necessary prerequisite for conscious perception; is-a 'prerequisites' is loose. Quotation withheld because this record is not cleared for redistribution. sensory evidence —contrasted-with→ previous exposure sensory evidence previous exposure strength of the relation: 1 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but sensory evidence and previous exposure are the TWO FACTORS that controlled visibility; contrasted-with is loose. Quotation withheld because this record is not cleared for redistribution. EVIDENCE CORRECTED (RE-GROUNDED) · sensory evidence —causes→ gamma band responses sensory evidence gamma band responses EVIDENCE CORRECTED: RE-GROUNDED. The old span said hGBR rather than the endpoint's own name. This sentence names both and states the dependence in its careful form - gamma band responses 'SOLELY reflected sensory evidence', while subjective reports were modulated by two things. — strength of the relation: 0.95 Quotation withheld because this record is not cleared for redistribution. EVIDENCE CORRECTED (RE-GROUNDED FROM A NEITHER-ENDPOINT SPAN) · previous exposure —causes→ conscious perception previous exposure conscious perception EVIDENCE CORRECTED: RE-GROUNDED FROM A NEITHER-ENDPOINT SPAN. The old span named neither term - it described what subjects reported. This sentence names both and states the DESIGN: 'a new experimental paradigm in which CONSCIOUS PERCEPTION…'. The causal claim is the manipulation, not an observed association. — strength of the relation: 0.95 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but the span writes 'reported to perceive', not 'conscious perception'. Quotation withheld because this record is not cleared for redistribution. sensory evidence —operationalised-as→ degradation sensory evidence degradation strength of the relation: 1 Quotation withheld because this record is not cleared for redistribution. EVIDENCE CORRECTED (RE-GROUNDED) · conscious perception —operationalised-as→ subjective task conscious perception subjective task EVIDENCE CORRECTED: RE-GROUNDED. The old span described the subjective task without naming conscious perception. This sentence names both and says WHY the task stands for the concept: it addresses the neural profile correlating with subjective reports about conscious perception. — strength of the relation: 1 Quotation withheld because this record is not cleared for redistribution. long-range integration —same-as→ neural correlates of consciousness long-range integration neural correlates of consciousness strength of the relation: 0.6 — the record marks this weak Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but theories PROPOSE that conscious experience is grounded in long-range integration; same-as is loose and attributed. Quotation withheld because this record is not cleared for redistribution. RETRACTED ('part of the same X' IS 'part-of', AND THE SCHEMA HAS THAT TYPE) · hGBR —same-as→ lGBR hGBR lGBR RETRACTED: 'part of the same X' IS 'part-of', AND THE SCHEMA HAS THAT TYPE. The edge is 'hGBR --same-as--> lGBR'. The span: '…that lGBR and hGBR are part of the same broadband process…' Two things being parts of one process does not make them each other - and the relation the sentence states is available in the vocabulary, as two 'part-of' edges to the broadband process, which would also preserve the third term the identity edge deletes. THE AUTHOR DECLINES THE IDENTITY IN THE SAME BREATH, and the tag is stronger than the sentence it quotes. 'Suggesting' is the authors reporting what a figure is consistent with, not what they have shown. — strength of the relation: 0.8 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but the span says the result is 'SUGGESTING' lGBR and hGBR are part of the same broadband process; same-as is hedged. Quotation withheld because this record is not cleared for redistribution. person-selective —operationalised-as→ catch images person-selective catch images strength of the relation: 0.95 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but person-selectivity was judged by COMPARISON WITH catch images; operationalised-as is loose. Quotation withheld because this record is not cleared for redistribution. gamma band responses —distinct-from→ conscious perception gamma band responses conscious perception strength of the relation: 0.9 Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but local gamma increases 'MIGHT thus reflect' unconscious processing; distinct-from is hedged. Quotation withheld because this record is not cleared for redistribution. previous exposure —causes→ conscious perception previous exposure conscious perception strength of the relation: 0.95 · note: RE-GROUNDS another row of this record: the old span named NEITHER endpoint. Quotation withheld because this record is not cleared for redistribution. repeated-measures ANOVA repeated-measures ANOVA Quotation withheld because this record is not cleared for redistribution. t-test t-test Quotation withheld because this record is not cleared for redistribution. Wilcoxon rank-sum test Wilcoxon rank-sum test Quotation withheld because this record is not cleared for redistribution. false discovery rate correction false discovery rate correction Quotation withheld because this record is not cleared for redistribution. Monte Carlo simulation Monte Carlo simulation Quotation withheld because this record is not cleared for redistribution. statistical power statistical power 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. standard deviation standard deviation Quotation withheld because this record is not cleared for redistribution. repeated-measures ANOVA repeated-measures ANOVA Quotation withheld because this record is not cleared for redistribution. Wilcoxon rank-sum test Wilcoxon rank-sum test Quotation withheld because this record is not cleared for redistribution. false discovery rate false discovery rate Quotation withheld because this record is not cleared for redistribution. Post hoc power analysis Post hoc power analysis Quotation withheld because this record is not cleared for redistribution. Monte Carlo simulations Monte Carlo simulations Quotation withheld because this record is not cleared for redistribution. F F Quotation withheld because this record is not cleared for redistribution. SEM SEM Quotation withheld because this record is not cleared for redistribution. Both experimental routes to conscious perception worked: reducing image degradation and having previously seen the image each raised the rate of 'seen' reports. Quotation withheld because this record is not cleared for redistribution. The two manipulations boosted subjective visibility to a statistically indistinguishable degree and did not interact. Quotation withheld because this record is not cleared for redistribution. In the larger sample of healthy controls, previous exposure and sensory evidence each significantly affected subjective perception. Quotation withheld because this record is not cleared for redistribution. Category-specific gamma responses were larger on trials where the person was reported seen, replicating the earlier result the study set out to test. Quotation withheld because this record is not cleared for redistribution. High-gamma responses were modulated by sensory evidence on 6 of 7 person-specific electrodes, and none of them by previous exposure. Quotation withheld because this record is not cleared for redistribution. A post hoc power analysis showed the null effect of previous exposure was not a detection failure. Quotation withheld because this record is not cleared for redistribution. Low and high gamma effects formed one continuous broadband response starting near 50 Hz rather than two distinct phenomena. Quotation withheld because this record is not cleared for redistribution. Because local gamma does not track conscious perception invariantly across the two routes to it, it cannot be the mechanism directly responsible for conscious perception. Quotation withheld because this record is not cleared for redistribution. both lower degradation and prior exposure raised the proportion of trials where a person was reported seen Quotation withheld because this record is not cleared for redistribution. the two manipulations boosted subjective perception to a statistically indistinguishable degree, with no interaction Quotation withheld because this record is not cleared for redistribution. in 24 healthy controls both previous exposure and sensory evidence significantly affected subjective perception Quotation withheld because this record is not cleared for redistribution. and again in eight subjects using an 11-point perceptual rating scale rather than a yes/no report Quotation withheld because this record is not cleared for redistribution. gamma tracked sensory evidence on 6 of 7 person-specific electrodes and prior exposure on none Quotation withheld because this record is not cleared for redistribution. the population analysis agreed: sensory evidence significant from 100 to 450 ms, previous exposure at p > 0.2 in every window Quotation withheld because this record is not cleared for redistribution. the null was not a power failure — the test had 0.94 power to detect a 30% change uncorrected, 0.9 corrected Quotation withheld because this record is not cleared for redistribution. the paper did replicate the original positive result: gamma was higher on trials where the person was consciously perceived, on 5 of 7 electrodes Quotation withheld because this record is not cleared for redistribution. person-specific gamma appeared on 7 electrodes across 5 patients, all on lateral occipital cortex and fusiform gyrus Quotation withheld because this record is not cleared for redistribution. the person-vs-background difference ran from about 50 Hz upward, indicating one broadband process rather than two bands Quotation withheld because this record is not cleared for redistribution. false alarms on background-only catch trials averaged 1.5 of 44, so the visibility reports were reliable Quotation withheld because this record is not cleared for redistribution. neural correlates of consciousness neural correlates of consciousness Quotation withheld because this record is not cleared for redistribution. gamma band responses gamma band responses Quotation withheld because this record is not cleared for redistribution. contrastive method contrastive method Quotation withheld because this record is not cleared for redistribution. person-selective person-selective Quotation withheld because this record is not cleared for redistribution. contrastive method contrastive method Quotation withheld because this record is not cleared for redistribution. Sensory evidence Sensory evidence Quotation withheld because this record is not cleared for redistribution. Previous exposure Previous exposure Quotation withheld because this record is not cleared for redistribution. power power Quotation withheld because this record is not cleared for redistribution. familiarization phase familiarization phase Quotation withheld because this record is not cleared for redistribution. catch trials catch trials Quotation withheld because this record is not cleared for redistribution. sensory evidence sensory evidence Quotation withheld because this record is not cleared for redistribution. previous exposure previous exposure Quotation withheld because this record is not cleared for redistribution. percentage of “seen” responses percentage of “seen” responses Quotation withheld because this record is not cleared for redistribution. hGBR hGBR Quotation withheld because this record is not cleared for redistribution. relative power relative power Quotation withheld because this record is not cleared for redistribution. MNI coordinates MNI coordinates Quotation withheld because this record is not cleared for redistribution. 6 — epilepsy patients with intracranial electrodes who performed the main experiment Quotation withheld because this record is not cleared for redistribution. 62 — electrodes free of epileptic activity that entered the analysis Quotation withheld because this record is not cleared for redistribution. seven — electrodes showing person-specific high gamma enhancement, in five patients Quotation withheld because this record is not cleared for redistribution. 85% (6/7) — person-specific electrodes whose high gamma tracked sensory evidence, versus none for previous exposure Quotation withheld because this record is not cleared for redistribution. 70% (5/7) — person-specific electrodes showing sustained gamma on consciously perceived trials Quotation withheld because this record is not cleared for redistribution. 0.94 and 0.9 — statistical power to detect a 30% change, uncorrected and corrected Quotation withheld because this record is not cleared for redistribution. 24 — healthy control subjects in the psychophysical replication Quotation withheld because this record is not cleared for redistribution. 60% to 90% in 5% steps — range of image noise levels used to titrate visibility Quotation withheld because this record is not cleared for redistribution. Forty-four — trials acquired per experimental condition in the patient experiment Quotation withheld because this record is not cleared for redistribution. six patients — intracranial sample Quotation withheld because this record is not cleared for redistribution. 24 healthy human subjects — psychophysical control sample Quotation withheld because this record is not cleared for redistribution. 62 electrodes — contacts free of epileptic activity that were examined Quotation withheld because this record is not cleared for redistribution. 7 electrodes, 5 patients — person-specific electrodes found Quotation withheld because this record is not cleared for redistribution. 85% (6/7) — person-specific electrodes modulated by sensory evidence Quotation withheld because this record is not cleared for redistribution. 70% (5/7) — person-specific electrodes showing higher gamma on consciously perceived trials Quotation withheld because this record is not cleared for redistribution. 0.94 and 0.9 — statistical power to detect a 30% change, uncorrected and corrected Quotation withheld because this record is not cleared for redistribution. 30–70 Hz and 70–150 Hz — the low and high gamma ranges analysed Quotation withheld because this record is not cleared for redistribution. 150 ms — duration of the degraded image presentation Quotation withheld because this record is not cleared for redistribution. 100–500 ms — the post-stimulus analysis window, split into eight 50 ms bins Quotation withheld because this record is not cleared for redistribution. 60% to 90% in 5% steps — the noise levels used to degrade images Quotation withheld because this record is not cleared for redistribution. ∼70% — the recognition performance the individual degradation thresholds targeted Quotation withheld because this record is not cleared for redistribution. 148 pictures, 22 catch images — the patient stimulus set Quotation withheld because this record is not cleared for redistribution. 44 trials per condition — trials acquired per condition in the patients Quotation withheld because this record is not cleared for redistribution. 11 experimental blocks — blocks in the main experiment, each with a familiarization and a test phase Quotation withheld because this record is not cleared for redistribution. mean 1.5, SD 2.3 — false alarms on the 44 background-only catch trials Quotation withheld because this record is not cleared for redistribution. −400 to −100 ms — the prestimulus baseline for power normalisation 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/10.1523/jneurosci.2051-12.2012.