Cortical distance, not cancellation, dominates inter-subject EEG gamma rhythm amplitude.

The neurophysiological response to visual stimulation in both humans and animals is characterized by an increase in high frequency amplitude peaking in the gamma range (40-100Hz) and a suppression of low frequency amplitude peaking in the alpha range (10-16Hz). Due to the large number of studies linking amplitude and peak frequency to perception and neurological disorders, there is great interest in understanding the basis of inter-subject variability in gamma and alpha responses. To address this, we measured gamma and alpha amplitude and peak frequency of response to visual stimulation in 42 healthy humans.