Spindle frequencies. For each of the five laminar, five sEEG, and two
ECoG subjects, the peak frequency (between 11 and 17 Hz) was computed for all
human-marked spindles and the mean peak frequency across all spindles is plotted
as one point for each channel. For laminar subjects, five of the channels are
plotted–spindles were marked based on evaluation of all channels. For the
sEEG and ECoG subjects, spindles were marked on an individual-channel basis, and
all scored channels are plotted. Color indicates the type of recording. Note
that laminar recordings were collected from cortex identified as probably
epileptogenic.