title: High gamma power is phase-locked to theta oscillations in human neocortex.
abstract: We observed robust coupling between the high- and low-frequency bands of ongoing electrical activity in the human brain. In particular, the phase of the low-frequency theta (4 to 8 hertz) rhythm modulates power in the high gamma (80 to 150 hertz) band of the electrocorticogram, with stronger modulation occurring at higher theta amplitudes. Furthermore, different behavioral tasks evoke distinct patterns of theta/high gamma coupling across the cortex. The results indicate that transient coupling between low- and high-frequency brain rhythms coordinates activity in distributed cortical areas, providing a mechanism for effective communication during cognitive processing in humans.
authors.affiliation: Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94720, USA. rcanolty@berkeley.edu
authors.forename: R T
authors.initials: RT
authors.lastname: Canolty
authors.forename: E
authors.initials: E
authors.lastname: Edwards
authors.forename: S S
authors.initials: SS
authors.lastname: Dalal
authors.forename: M
authors.initials: M
authors.lastname: Soltani
authors.forename: S S
authors.initials: SS
authors.lastname: Nagarajan
authors.forename: H E
authors.initials: HE
authors.lastname: Kirsch
authors.forename: M S
authors.initials: MS
authors.lastname: Berger
authors.forename: N M
authors.initials: NM
authors.lastname: Barbaro
authors.forename: R T
authors.initials: RT
authors.lastname: Knight
mesh_terms: D000328:Adult; D001288:Attention; D001307:Auditory Perception; D003071:Cognition; D004567:Electrodes, Implanted; D004594:Electrophysiology; D004827:Epilepsy / Q000503:physiopathology / Q000601:surgery; D005260:Female; D006801:Humans; D008568:Memory; D008606:Mental Processes; D008875:Middle Aged; D019579:Neocortex / Q000502:physiology*; D011597:Psychomotor Performance; D013826:Theta Rhythm; D014796:Visual Perception