Combined EEG and MEG recordings of visual 40 Hz responses to illusory triangles in human.
EEG and MEG were simultaneously recorded to study the visual gamma-band (30-70 Hz) responses. The electrical gamma-band response phase-locked to stimulus onset can be subdivided into a central component at 39 Hz and an occipital component at 36 Hz. A new high-frequency magnetic phase-locked response recorded over the occipital lobe is described. Its topography is complex and probably reflects the activity of multiple sources. Both electrical and magnetic high-frequency responses differ in topography from the low-frequency responses in the same latency range, suggesting that at least partially distinct sources are involved. The existence of a non-phase-locked 40 Hz component around 280 ms is confirmed in EEG data but is not detectable in MEG data.
Tallon-Baudry
C
C
Brain Signals and Processes Laboratory, INSERM U280, Lyon, France.
Bertrand
O
O
Wienbruch
C
C
Ross
B
B
Pantev
C
C
D000328:Adult; D004569:Electroencephalography; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D009903:Optical Illusions; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology