title: Synchronous cortical gamma-band activity in task-relevant cognition.
abstract: Widespread synchronous oscillatory activity, particularly in the gamma ('40 Hz') band, has been postulated to exist in the brain as a mechanism underlying binding. A new method of examining phase synchronicity across multiple electrode sites in specific EEG frequency bands as a function of time was employed, in a conventional cognitive ERP paradigm in 40 normal subjects. A significant late post-stimulus gamma synchronicity response occurred for task-relevant stimuli, whereas for task-irrelevant stimuli no such response was evident. However, an early response was seen for both task-relevant and irrelevant stimuli. This is the first empirical demonstration that widespread synchronous high frequency oscillations occur in humans in relation to cognition.
authors.affiliation: Cognitive Neuroscience Unit, Westmead Hospital, Sydney, NSW, Australia.
authors.forename: A R
authors.initials: AR
authors.lastname: Haig
authors.forename: E
authors.initials: E
authors.lastname: Gordon
authors.forename: J J
authors.initials: JJ
authors.lastname: Wright
authors.forename: R A
authors.initials: RA
authors.lastname: Meares
authors.forename: H
authors.initials: H
authors.lastname: Bahramali
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D002540:Cerebral Cortex / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory / Q000502:physiology; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008875:Middle Aged; D011597:Psychomotor Performance / Q000502:physiology*; D013997:Time Factors