title: EEG coherence: topography and frequency structure.
abstract: Topographical patterns of bipolar EEG coherence are frequency specific, indicating the presence of diverse neuroanatomical and neurophysiological factors in EEG production. Bipolar EEG coherence values were calculated at 50 frequency bins ranging from 3 to 28 Hz for 39 coherence pairs. Data were derived from 4.25 min of resting EEG obtained from 106 healthy adult male subjects and analyzed in 0.5 Hz bins by Fourier transform methods. Frequency bands were clearly separated at 8.5 and 13 Hz, with a less distinct separations at 6 and 20 Hz. Within pair (non-topographic) and across pair (topographic), measures gave similar patterns of separation. Significant pathways were primarily anterior-posterior interhemispheric or perpendicular to the anterior-posterior axis. There was little difference between left and right for comparable pairs. Theta band coherent activity involves distinct midline and temporal sources, with temporal sources showing anterior/posterior differentiation. In contrast, alpha activity has a distinct posterior focus, while beta activity shows no clear global structure. A spatially homogeneous model based on characteristics of thalamocortical connectivity accounts for much of the data, but departures from the model indicate the contribution of other neural factors to coherence.
authors.affiliation: Henri Begleiter Neurodynamics Laboratory, Department of Psychiatry, SUNY Downstate Medical Center, 450 Clarkson Ave., Brooklyn, NY, USA. David.Chorlian@downstate.edu
authors.forename: David Balin
authors.initials: DB
authors.lastname: Chorlian
authors.forename: Madhavi
authors.initials: M
authors.lastname: Rangaswamy
authors.forename: Bernice
authors.initials: B
authors.lastname: Porjesz
mesh_terms: D000328:Adult; D000513:Alpha Rhythm; D001931:Brain Mapping / Q000379:methods*; D002540:Cerebral Cortex / Q000033:anatomy & histology / Q000502:physiology*; D004569:Electroencephalography / Q000379:methods*; D005071:Evoked Potentials / Q000502:physiology*; D005583:Fourier Analysis; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008959:Models, Neurological; D009434:Neural Pathways / Q000033:anatomy & histology / Q000502:physiology; D012815:Signal Processing, Computer-Assisted; D013788:Thalamus / Q000502:physiology; D013826:Theta Rhythm; D055815:Young Adult