Increased gamma-band synchrony precedes switching of conscious perceptual objects in binocular rivalry.
Gamma-band neural synchrony has been proposed as a correlate of consciousness and as a solution for the binding problem. Research on visual working memory and the perception of coherent images in ambiguous figures supports this view. To test the relationship between perceptual consciousness and gamma synchrony, we recorded electroencephalogram activity while participants were presented with rivalling visual images to each eye. Participants pressed buttons to indicate which image they were perceiving, and response-locked phase-locking values (6-60 Hz) were calculated from the electroencephalogram time series. Results revealed transient bursts of increased global phase synchrony in the gamma-band peaking approximately 425 and approximately 260 ms preresponse. This suggests that global gamma synchrony is associated with the emergence of a coherent conscious percept.
Doesburg
Sam M
SM
Psychophysics and Cognitive Neuroscience Laboratory, Department of Psychology, The University of British Columbia, Vancouver, Canada BC V6T1Z4. sam@psych.ubc.ca
Kitajo
Keiichi
K
Ward
Lawrence M
LM
D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D003243:Consciousness / Q000502:physiology*; D003344:Cortical Synchronization; D004569:Electroencephalography / Q000379:methods; D005074:Evoked Potentials, Visual; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D010775:Photic Stimulation / Q000379:methods; D013997:Time Factors; D015357:Vision Disparity / Q000502:physiology*; D015348:Vision, Binocular / Q000502:physiology*; D014793:Visual Cortex / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*