Rhythms of consciousness: binocular rivalry reveals large-scale oscillatory network dynamics mediating visual perception.
Consciousness has been proposed to emerge from functionally integrated large-scale ensembles of gamma-synchronous neural populations that form and dissolve at a frequency in the theta band. We propose that discrete moments of perceptual experience are implemented by transient gamma-band synchronizat...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2009-07-01
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| Series: | PLoS ONE |
| Online Access: | http://europepmc.org/articles/PMC2702101?pdf=render |
| _version_ | 1818291525546672128 |
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| author | Sam M Doesburg Jessica J Green John J McDonald Lawrence M Ward |
| author_facet | Sam M Doesburg Jessica J Green John J McDonald Lawrence M Ward |
| author_sort | Sam M Doesburg |
| collection | DOAJ |
| description | Consciousness has been proposed to emerge from functionally integrated large-scale ensembles of gamma-synchronous neural populations that form and dissolve at a frequency in the theta band. We propose that discrete moments of perceptual experience are implemented by transient gamma-band synchronization of relevant cortical regions, and that disintegration and reintegration of these assemblies is time-locked to ongoing theta oscillations. In support of this hypothesis we provide evidence that (1) perceptual switching during binocular rivalry is time-locked to gamma-band synchronizations which recur at a theta rate, indicating that the onset of new conscious percepts coincides with the emergence of a new gamma-synchronous assembly that is locked to an ongoing theta rhythm; (2) localization of the generators of these gamma rhythms reveals recurrent prefrontal and parietal sources; (3) theta modulation of gamma-band synchronization is observed between and within the activated brain regions. These results suggest that ongoing theta-modulated-gamma mechanisms periodically reintegrate a large-scale prefrontal-parietal network critical for perceptual experience. Moreover, activation and network inclusion of inferior temporal cortex and motor cortex uniquely occurs on the cycle immediately preceding responses signaling perceptual switching. This suggests that the essential prefrontal-parietal oscillatory network is expanded to include additional cortical regions relevant to tasks and perceptions furnishing consciousness at that moment, in this case image processing and response initiation, and that these activations occur within a time frame consistent with the notion that conscious processes directly affect behaviour. |
| first_indexed | 2024-12-13T02:45:27Z |
| format | Article |
| id | doaj.art-6ffc3a3c62a5406f9177d23b2be7e923 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-13T02:45:27Z |
| publishDate | 2009-07-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-6ffc3a3c62a5406f9177d23b2be7e9232022-12-22T00:02:11ZengPublic Library of Science (PLoS)PLoS ONE1932-62032009-07-0147e614210.1371/journal.pone.0006142Rhythms of consciousness: binocular rivalry reveals large-scale oscillatory network dynamics mediating visual perception.Sam M DoesburgJessica J GreenJohn J McDonaldLawrence M WardConsciousness has been proposed to emerge from functionally integrated large-scale ensembles of gamma-synchronous neural populations that form and dissolve at a frequency in the theta band. We propose that discrete moments of perceptual experience are implemented by transient gamma-band synchronization of relevant cortical regions, and that disintegration and reintegration of these assemblies is time-locked to ongoing theta oscillations. In support of this hypothesis we provide evidence that (1) perceptual switching during binocular rivalry is time-locked to gamma-band synchronizations which recur at a theta rate, indicating that the onset of new conscious percepts coincides with the emergence of a new gamma-synchronous assembly that is locked to an ongoing theta rhythm; (2) localization of the generators of these gamma rhythms reveals recurrent prefrontal and parietal sources; (3) theta modulation of gamma-band synchronization is observed between and within the activated brain regions. These results suggest that ongoing theta-modulated-gamma mechanisms periodically reintegrate a large-scale prefrontal-parietal network critical for perceptual experience. Moreover, activation and network inclusion of inferior temporal cortex and motor cortex uniquely occurs on the cycle immediately preceding responses signaling perceptual switching. This suggests that the essential prefrontal-parietal oscillatory network is expanded to include additional cortical regions relevant to tasks and perceptions furnishing consciousness at that moment, in this case image processing and response initiation, and that these activations occur within a time frame consistent with the notion that conscious processes directly affect behaviour.http://europepmc.org/articles/PMC2702101?pdf=render |
| spellingShingle | Sam M Doesburg Jessica J Green John J McDonald Lawrence M Ward Rhythms of consciousness: binocular rivalry reveals large-scale oscillatory network dynamics mediating visual perception. PLoS ONE |
| title | Rhythms of consciousness: binocular rivalry reveals large-scale oscillatory network dynamics mediating visual perception. |
| title_full | Rhythms of consciousness: binocular rivalry reveals large-scale oscillatory network dynamics mediating visual perception. |
| title_fullStr | Rhythms of consciousness: binocular rivalry reveals large-scale oscillatory network dynamics mediating visual perception. |
| title_full_unstemmed | Rhythms of consciousness: binocular rivalry reveals large-scale oscillatory network dynamics mediating visual perception. |
| title_short | Rhythms of consciousness: binocular rivalry reveals large-scale oscillatory network dynamics mediating visual perception. |
| title_sort | rhythms of consciousness binocular rivalry reveals large scale oscillatory network dynamics mediating visual perception |
| url | http://europepmc.org/articles/PMC2702101?pdf=render |
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