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Cited by 716Neural dynamics and brain functionPhilosophy and Theoretical ScienceVisual perception and processing mechanisms

Synchronization of neural activity across cortical areas correlates with conscious perception

Open access
Melloni, Lucia, Molina, Carlos, Pena, Marcela, Torres, David, Singer, Wolf, Rodriguez, Eugenio·2007·The Journal of Neuroscience
DOI 10.1523/jneurosci.4623-06.2007PMC PMC6672558
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Abstract

Subliminal stimuli can be deeply processed and activate similar brain areas as consciously perceived stimuli. This raises the question which signatures of neural activity critically differentiate conscious from unconscious processing. Transient synchronization of neural activity has been proposed as a neural correlate of conscious perception. Here we test this proposal by comparing the electrophysiological responses related to the processing of visible and invisible words in a delayed matching to sample task. Both perceived and nonperceived words caused a similar increase of local (gamma) oscillations in the EEG, but only perceived words induced a transient long-distance synchronization of gamma oscillations across widely separated regions of the brain. After this transient period of temporal coordination, the electrographic signatures of conscious and unconscious processes continue to diverge. Only words reported as perceived induced (1) enhanced theta oscillations over frontal regions during the maintenance interval, (2) an increase of the P300 component of the event-related potential, and (3) an increase in power and phase synchrony of gamma oscillations before the anticipated presentation of the test word. We propose that the critical process mediating the access to conscious perception is the early transient global increase of phase synchrony of oscillatory activity in the gamma frequency range.

AI snapshot

Written from the paper’s full text.

TL;DR

In a masked-word delayed matching-to-sample EEG study, consciously perceived and unperceived words produced similar local gamma activity, but only perceived words triggered a transient long-distance synchronization of gamma oscillations across cortical areas. The authors propose this early global phase synchrony as a critical event mediating access to conscious perception.

Key findings

  • Visible words were correctly classified 94.5% of the time (mean d′ = 3.85), whereas invisible words dropped to chance (52.2%; mean d′ = 0.16); reaction times were shorter for visible than invisible words (923 vs 1418 ms).
  • Both visible and invisible words increased local gamma oscillations, but only visible words induced transient long-distance gamma phase synchrony at 50–57 Hz from 80 to 130 ms after sample-word presentation (F(1,14) = 5.041; p = 0.044), with no concurrent difference in gamma amplitude or ERPs.
  • Only visible words later produced a frontocentral P3a-like positivity from 130 to 430 ms, peaking at 240 ms (F(1,14) = 37.766; p = 0.00002; 2.3394 µV difference), enhanced frontal theta (5–6 Hz) during maintenance, and increased gamma power and phase synchrony before test-word presentation (synchrony: F(1,14) = 11.803, p = 0.005; power: F(1,14) = 8.006, p = 0.015).
  • In a separate unconscious priming experiment (n = 20), invisible primes still produced a 15 ms congruent-versus-incongruent reaction-time effect (F(1,19) = 8.981; p = 0.007), indicating deep processing without awareness.

Methods

  • Experiment 1: 15 healthy right-handed native Spanish speakers performed a two-alternative forced-choice delayed matching-to-sample task (320 trials); a 33 ms sample word was rendered visible or invisible by mask luminance, followed 533 ms later by a test word, with control conditions to subtract mask-stream responses.
  • Experiment 2: 20 subjects performed an unconscious semantic priming task with the same word set and masks; invisible primes were semantically congruent or incongruent with targets.
  • EEG was recorded from a 64-electrode geodesic sensor net at 1000 Hz. Analyses included ERPs, time-frequency power, and phase-locking value (PLV) for phase synchrony, with permutation tests and within-subject ANOVAs; topographic synchrony used a conservative threshold of p < 0.00005.

Limitations

  • The paper states that the transient long-distance synchronization is not entirely compatible with models predicting sustained activity for conscious stimuli, because synchrony lasted about 100 ms but reached significance only for about 50 ms.
  • The paper states that the mechanism by which long-distance synchronization affects subsequent cognitive processes remains to be clarified, and whether early synchronization itself is phenomenal awareness or whether awareness emerges from later processes is unresolved.
  • The paper notes that precise onset of enhanced theta could not be determined because long windows were needed for low-frequency oscillations; it also reports that luminance and volume-conduction confounds were addressed by control subtractions and phase-lag analyses, though these remain methodological considerations evident from the design.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1523/jneurosci.4623-06.2007

Cites

49 of 49 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

0 of 23 cited sources checked · 0 supported · 0 flagged

  • Findingown data

    Reaction times were significantly shorter in the visible compared with the invisible condition (923 vs 1418 ms).

    “Reaction times were significantly shorter in the visible com- pared with the invisible condition (923 and 1418 ms, respectively; F (1,14) ϭ 76.139; p ϭ 0.000018), despite the fact that speed of response was not stressed in the task.”
    Quote in the paperNot a substantial claim
  • Findingown data

    In the visible condition, numerous electrode pairs, both within and across hemispheres, showed significant phase-locking between occipital, parietal, and frontal sites in the time window 40-180 ms after sample-word presentation.

    “In the visible condition, in contrast, numerous electrode pairs, both within and across hemispheres, showed significant phase-locking between occipital, parietal, and frontal sites in the time window 40 -180 ms after sample-word presentation.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The EEG response to the masking stimuli is equivalent in experimental and control conditions, so subtracting control from experimental traces isolates the response to the sample word.
    • Rests on an assumption: The filter that eliminated the continuous 50 Hz AC component kept the biological 50 Hz signal intact.
  • Findingown data

    Both perceived and nonperceived words caused a similar increase of local gamma oscillations in the EEG.

    “Both perceived and nonperceived words caused a similar increase of local (gamma) oscillations in the EEG”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The EEG response to the masking stimuli is equivalent in experimental and control conditions, so subtracting control from experimental traces isolates the response to the sample word.
  • Findingown data

    The first significant difference between visible and invisible words was observed from 80 to 130 ms after sample-word presentation.

    “The first significant difference between visible and invisible words was observed from 80 to 130 ms after sample-word presentation.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The EEG response to the masking stimuli is equivalent in experimental and control conditions, so subtracting control from experimental traces isolates the response to the sample word.
  • Findingown data

    Only words reported as perceived induced an increase in power and phase synchrony of gamma oscillations before the anticipated presentation of the test word.

    “an increase in power and phase synchrony of gamma oscillations before the anticipated presentation of the test word.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The EEG response to the masking stimuli is equivalent in experimental and control conditions, so subtracting control from experimental traces isolates the response to the sample word.
    • Rests on an assumption: The filter that eliminated the continuous 50 Hz AC component kept the biological 50 Hz signal intact.
    • Rests on an assumption: Subjective report of word visibility is a valid index of conscious perception.
  • May combine two claims. 25
  • Classified as probably not a substantial claim. 10

  • May combine two claims.

    Findingown data

    Patterns of gamma activity were spatially homogeneous and similar for visible and invisible conditions.

    “the patterns of gamma activity were spatially homogeneous and similar for the two conditions”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The EEG response to the masking stimuli is equivalent in experimental and control conditions, so subtracting control from experimental traces isolates the response to the sample word.
    • Rests on an assumption: The filter that eliminated the continuous 50 Hz AC component kept the biological 50 Hz signal intact.

  • May combine two claims.

    Findingown data

    In the visible condition, 94.5% of sample words were classified correctly, with mean d' 3.85, significantly above chance.

    “Behavioral results showed that, in the experimental condition in which sample words could be perceived, 94.5% of the words were classified correctly (F (1,14) ϭ 904.5; p Ͻ 0.001), the mean dЈ being 3.85, which implies a highly significant difference from chance (F (1,14) ϭ 192.2; p Ͻ 0.001).”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In the invisible condition, performance dropped to chance level (52.2%) and mean d' did not differ from zero (d'=0.16).

    “Conversely, in the experimental condition that rendered sample words invisible, performance dropped to chance level (52.2%;F (1,14) ϭ 2.097; p ϭ 0.170), and the mean dЈ value did not differ from zero (dЈ ϭ 0.16; F (1,14) ϭ 2.598; p ϭ 0.129)”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In control conditions, success rates were 92.50 and 86.17%, with d' values 3.27 and 2.50, indicating participants could detect control words.

    “In control conditions, the success rates were 92.50 and 86.17%, and the respective dЈ values were 3.27 and 2.50, indicating that participants were able to detect the control words.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    There was a significant increase in phase synchrony in the frequency band 63-83 Hz in the interval 185-240 ms after test-word presentation, which did not differ between visible and invisible conditions.

    “First, there was a significant increase in phase synchrony in the frequency band from 63 to 83 Hz in the interval 185-240 ms after test-word presentation (visible vs baseline: F (1,14) ϭ 22.869, p Ͻ 0.001; invisible vs baseline: F (1,14) ϭ 18.720, p ϭ 0.001; visible vs invisible conditions: F (1,14) ϭ 0.199, p ϭ 0.663)”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The EEG response to the masking stimuli is equivalent in experimental and control conditions, so subtracting control from experimental traces isolates the response to the sample word.
    • Rests on an assumption: The filter that eliminated the continuous 50 Hz AC component kept the biological 50 Hz signal intact.

  • May combine two claims.

    Findingown data

    Immediately after test-word presentation, both phase synchrony and gamma power were significantly higher in the visible than in the invisible condition.

    “A third and more delayed difference between the visible and invisible conditions was observed immediately after test-word presentation.Here, both phase synchrony and gamma power were significantly higher during the visible than the invisible conditions.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The EEG response to the masking stimuli is equivalent in experimental and control conditions, so subtracting control from experimental traces isolates the response to the sample word.
    • Rests on an assumption: The filter that eliminated the continuous 50 Hz AC component kept the biological 50 Hz signal intact.

  • May combine two claims.

    Findingown data

    There was a significant increase in power of gamma oscillations in a broad frequency range (36-85 Hz) during 155-230 ms after test-word presentation, which did not differ between visible and invisible conditions.

    “Second, there was a significant increase in power of gamma oscillations in a broad frequency range (36 -85 Hz) during the interval of 155-230 ms after test-word presentation (visible vs baseline: F (1,14) ϭ 63.524, p Ͻ 0.001; invisible vs baseline: F (1,14) ϭ 52.626, p Ͻ 0.001; visible vs invisible condition: F (1,14) ϭ 2.030, p ϭ 0.180).”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The EEG response to the masking stimuli is equivalent in experimental and control conditions, so subtracting control from experimental traces isolates the response to the sample word.
    • Rests on an assumption: The filter that eliminated the continuous 50 Hz AC component kept the biological 50 Hz signal intact.

  • May combine two claims.

    Findingown data

    During the interval of enhanced phase-locking, neither the ERPs nor the induced gamma oscillations differed between conditions.

    “During the interval of enhanced phase-locking, neither the ERPs nor the induced gamma oscillations differed between conditions”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Our results show increased neural synchrony for the visible condition, which lasts ~100 ms but reaches significance only during a short time window (~50 ms).

    “Our results show increased neural synchrony for the visible condition, which lasts ϳ100 ms but reaches significance only during a short time window (ϳ50 ms)”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In our experiment, the phase angles at which synchronization occurred were not centered on zero and exhibited considerable scatter.

    “In our experiment, the phase angles at which synchronization occurred were not centered on zero and exhibited considerable scatter (Ϯrads)”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The induced synchronization after test-word presentation occurred with much longer latency (~200 ms) and was in the range described in previous experiments.

    “In this case, the induced synchronization occurred with much longer latency (ϳ200 ms) and was in the range described in previous experiments.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Findingown data

    Consciously perceived stimuli give rise to an enhancement of a P3a-like component of the ERP and of sustained theta oscillations over frontal areas.

    “(2) an enhancement of a P3a-like component of the ERP and of sustained theta oscillations over frontal areas”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    Prime words, although not perceived, had a clear behavioral effect indicating that unconsciously perceived words are processed.

    “Prime words, although not perceived, had a clear behavioral effect indicating that the unconsciously perceived words are processed.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    The first and second peaks of synchronous activity occur only in the visible condition.

    “The first and second peaks occur only in the visible condition.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Findingown data

    In the window between 180 and 330 ms, the pattern of phase synchrony lateralizes over the left hemisphere and restricts to occipitoparietal electrodes.

    “In the window between 180 and 330 ms, the pattern of phase synchrony lateralizes over the left hemisphere and restricts to occipitoparietal electrodes.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Masked, briefly presented stimuli that cannot be reported can still be highly processed and even activate motor responses.

    “Stimuli that are masked and presented so briefly that they cannot be reported can still be highly processed and even activate motor responses (Marcel, 1983;Dehaene et al., 1998Dehaene et al., , 2001Dehaene et al., , 2004;;Naccache et al., 2005).”
    Quote in the paperSubstantial claim0 of 2 sources checked
    • cites Marcel, 1983

      Not checked in the free run.

    • cites Dehaene et al., 1998

      Not checked in the free run.

  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Beta and gamma frequency band phase synchrony is enhanced for consciously perceived stimuli and correlates with conscious perception in binocular rivalry.

    “Indeed, ␤ and gamma frequency band phase synchrony is enhanced for consciously perceived stimuli (Meador et al., 2002;Gross et al., 2004;Nakatani et al., 2005;Palva et al., 2005) and correlates with conscious perception in binocular rivalry (Fries et al., 1997(Fries et al., , 2002;;Srinivasan et al., 1999;Doesburg et al., 2005).”
    Quote in the paperSubstantial claim0 of 3 sources checked
    • cites Meador et al., 2002 source

      Not checked in the free run.

    • cites Fries et al., 1997

      Not checked in the free run.

    • cites Doesburg et al., 2005

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S1 (asserted). May combine two claims.

    Premisecitation

    The neural signature of unconscious perception is local coordination of neural activity and propagation along sensory processing pathways, whereas conscious perception requires global coordination of widely distributed neural activity by long-distance synchronization.

    “The neural signature of unconscious perception would be local coordination of neural activity and propagation along sensory processing pathways, whereas conscious perception would require global coordination of widely distributed neural activity by long-distance synchronization (Dehaene et al., 2006).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Dehaene et al., 2006

      Not checked in the free run.

  • May combine two claims.

    Premisereasoning

    Previous studies of synchronization in conscious perception investigated spatially restricted neural assemblies or did not distinguish local from global coordination.

    “However, these studies have investigated synchronization in spatially restricted neural assemblies, or without distinguishing between local and global coordination.”
    Quote in the paperSubstantial claim

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    The P3-like component has been related to the updating of contents kept in working memory.

    “The P3-like component has been related to the updating of contents kept in working memory (Donchin, 1981).”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites Donchin, 1981

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Premisecitation

    Frontal theta oscillations have been assigned a role in the maintenance of short-term memories.

    “Frontal theta oscillations have been assigned a role in the maintenance of short-term memories (Jensen and Tesche, 2002;Schack et al., 2005).”
    Quote in the paperNot a substantial claim0 of 2 sources checked
    • cites Jensen and Tesche, 2002

      Not checked in the free run.

    • cites Schack et al., 2005

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S3 (load-bearing).

    Study design and conductown data

    The necessity to use long windows for assessment of low-frequency oscillations precluded determination of the precise onset of enhanced theta.

    “Although it would have been interesting to see whether the theta enhancement started only after the episode of gamma phase-locking, the necessity to use long windows for the assessment of the low-frequency oscillations precluded determination of the precise onset of enhanced theta.”
    Quote in the paperNot a substantial claim
    • Rests on an assumption: The EEG response to the masking stimuli is equivalent in experimental and control conditions, so subtracting control from experimental traces isolates the response to the sample word.

  • May combine two claims.

    Study design and conductreasoning

    The contrast of visible-minus-invisible minus control-visible-minus-control-invisible removes remaining luminance effects, so persisting effects reflect processes related to conscious perception of the sample word.

    “This contrast should remove any remaining luminance effects, and persisting effects should only reflect processes related to conscious perception of the sample word.”
    Quote in the paperSubstantial claim
    • Rests on an assumption: The EEG response to the masking stimuli is equivalent in experimental and control conditions, so subtracting control from experimental traces isolates the response to the sample word.

  • May combine two claims.

    Interpretationown data

    Neural synchronization could last longer but is nonetheless transient.

    “suggesting that neural synchronization could last longer but is nonetheless transient.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Premisecitation

    Experiments on change blindness show that unattended objects could be fleetingly represented and reported but their representations disappear as soon as a new object is presented or if the eyes move to a new location.

    “experiments on the related phenomenon of change blindness show that unattended objects could be fleetingly represented and reported but that their representations disappear as soon as a new object is presented or if the eyes move to a new location (Landmann et al., 2003).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Landmann et al., 2003

      Not checked in the free run.

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    The brain can process information remarkably fast.

    “these results suggest that the brain can process information remarkably fast”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S4 (based).

    Interpretationnone given

    The fast stream of stimuli used in our experiment might have imposed pressure on perceptual processes, leading to a shortening of the processing time devoted to each stimulus.

    “First, the fast stream of stimuli used in our experiment might have imposed pressure on the perceptual processes, leading to a shortening of the processing time devoted to each stimulus.”
    Quote in the paperNot a substantial claim

  • May combine two claims.

    Interpretationreasoning

    The sustained activity often reported using such experimental paradigms could reflect the transfer or maintenance of a stable representation in working memory and is not necessarily a correlate of conscious perception itself.

    “Thus, the sustained activity often reported using such experimental paradigms could reflect the transfer or maintenance of a stable representation in working memory and are not necessarily a correlate of conscious perception itself.”
    Quote in the paperNot a substantial claim

  • Probably not a substantial claim: may not pass S2 (checkable).

    Interpretationreasoning

    The combination of the different methods applied here allows for a more detailed temporal characterization of the putative EEG events differentiating between conscious and unconscious processing.

    “The combination of the different methods applied here allows for a more detailed temporal characterization of the putative EEG events differentiating between conscious and unconscious processing.”
    Quote in the paperNot a substantial claim

  • Classified as probably not a substantial claim.

    Interpretationcitation

    This early wave of activation might be an essential correlate of conscious perception.

    “implying that this early wave of activation might be an essential correlate of conscious perception (Pins and Ffytche, 2003).”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites Pins and Ffytche, 2003

      Not checked in the free run.

  • May combine two claims.

    Interpretationreasoning

    Fast and transient large-scale synchronization enhances the saliency of activation patterns sufficiently to permit access to consciousness and thereby triggers a sequence of processes such as perception stabilization, maintenance in working memory, and generation of expectancies associated with conscious awareness.

    “Thus, it seems as if the fast and transient large-scale synchronization enhances the saliency of the activation patterns sufficiently to permit access to consciousness and thereby triggers a sequence of processes such as perception stabilization, maintenance in working memory, and generation of expectancies that are associated with conscious awareness.”
    Quote in the paperSubstantial claim

  • Classified as probably not a substantial claim.

    Study design and conductnone given

    In the control experiment with the subliminal priming task, we evaluated the depth of processing of the unperceived word using the same protocol as in the main experiment.

    “In addition, in the control experiment with the subliminal priming task, we evaluated the depth of processing of the unperceived word using the same protocol as in the main experiment.”
    Quote in the paperSubstantial claim

  • May combine two claims.

    Interpretationreasoning

    The key event mediating access to consciousness is the early long-distance synchronization of neural assemblies, rather than the mere depth of processing in the various cortical areas involved in written word processing.

    “Therefore, we consider it likely that the key event mediating access to consciousness is the early long-distance synchronization of neural assemblies, rather than the mere depth of processing in the various cortical areas involved in written word processing.”
    Quote in the paperSubstantial claim
33 of 33

  • The paper relies on this without support.

    The EEG response to the masking stimuli is equivalent in experimental and control conditions, so subtracting control from experimental traces isolates the response to the sample word.

    “This design enabled us to isolate the response to the sample word by subtracting the response elicited by the masking stimuli.”

  • The paper relies on this without support.

    The filter that eliminated the continuous 50 Hz AC component kept the biological 50 Hz signal intact.

    “a filter was designed that eliminated only the continuous 50 Hz (AC) component but kept the biological 50 Hz signal.”

  • The paper relies on this without support.

    Subjective report of word visibility is a valid index of conscious perception.

    “Only words reported as perceived induced”

  • The paper relies on this without support.

    The delayed matching to sample task involves language processing.

    “which agrees with the fact that the task involves language processing.”

  • The paper relies on this without support.

    Enhanced synchronization can be mimicked by volume conduction if it occurs with zero phase lag.

    “Enhanced synchronization can be mimicked by volume conduction if it occurs with zero phase lag.”

  • The paper relies on this without support.

    If observed synchronization were attributable to activation or inactivation of one or several generators, it should show up as a difference in induced gamma activity or ERPs between experimental conditions.

    “if the observed synchronization were attributable to activation or inactivation of one or several generators, it should show up as a difference in the induced gamma activity or in the ERPs between experimental conditions.”

  • The paper relies on this without support.

    Synchronization caused by volume conduction must occur with zero phase difference between electrodes.

    “synchronization caused by volume conduction must occur with zero phase difference between electrodes.”

  • The paper relies on this without support.

    Phase synchronization caused by volume conduction should exhibit a distance-dependent gradient on the scalp.

    “phase synchronization caused by volume conduction should exhibit a distancedependent gradient on the scalp”
8 of 8

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • Test-related gamma increase is placed before and after test presentation

    Minor

    The abstract places the increase in gamma power and phase synchrony before the test word, but the results place both measured increases after its presentation.

1 of 1

Cites

Flagged first, then by citations

Research works printed but not linked: 2

  1. Burgess, 1999, Methodological advances in the analysis of event-related desynchronization data: reliability and robust analysis, Vol 6, 139
  2. Wolfe JM (1999) in Fleeting memories: cognition of brief visual stimuli, Inattentional amnesia, ed Coltheart V (MIT, Cambridge, MA), pp 71–91.

Cited by

Sorted by citations

Related

Authors
Melloni, L., Molina, C., Pena, M., Torres, D., Singer, W., & Rodriguez, E.
Affiliations
  • Radboud University Nijmegen (NL)
  • Pontificia Universidad Católica de Chile (CL)
  • Goethe University Frankfurt (DE)
ORCID
Singer, Wolf
Venue
The Journal of Neuroscience
Publisher
Society for Neuroscience
Published
2007-03-14
Volume
27
Issue
11
Pages
2858-2865
ISSN
  • 0270-6474 (ISSN-L)
  • 1529-2401
DOI
10.1523/jneurosci.4623-06.2007
PMC
PMC6672558
OpenAlex
W1983939506
Semantic Scholar
b2ac15db0b7829efcb8dcbda723039a3df2b6f11
Cited by
716
References
49
Citations by year
2026: 12 · 2025: 16 · 2024: 21 · 2023: 23 · 2022: 39 · 2021: 31 · 2020: 31 · 2019: 50 · 2018: 24 · 2017: 49 · 2016: 40 · 2015: 45 · 2014: 52 · 2013: 36 · 2012: 44
FWCI
27.31
Type
journal article
Language
en
Open access
Licence
Locations
  • Journal of Neuroscience (publishedVersion, cc-by-nc-sa)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Americanae (AECID Library) (submittedVersion, other-oa)
  • LA Referencia (Red Federada de Repositorios Institucionales de Publicaciones Científicas) (submittedVersion, other-oa)
Topics
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Neural dynamics and brain function
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Philosophy and Theoretical Science
  • Life Sciences › Neuroscience › Cognitive Neuroscience › Visual perception and processing mechanisms
Keywords
conscious perception, subliminal perception, neuronal synchronization, gamma oscillations, phase synchronization, theta oscillations, P300, event-related potentials, delayed matching-to-sample, unconscious processes
MeSH terms
Adult, Cerebral Cortex, Consciousness, Cortical Synchronization, Female, Humans, Male, Neurons, Perception, Psychomotor Performance, Reaction Time

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