LFP responses to contrast reversal gratings and frequency analysis of the responses.

<p>(A) Left panel, raw LFP signal from a single channel during a single trial of visual stimulation by 4-Hz contrast reversal grating. Right panel, the black curve is the z-score signal for the trace shown in the left panel, and the red curve is the signal band-pass filtered at 6–10 Hz (2^nd harmonic response). (B) Upper panel, unfiltered LFP signals averaged over all trials in response to a 4-Hz contrast reversal grating (orientation = 135°) for 7 recording sites distributed along the medial-lateral axis. Lower panel, the z-score signal for the responses shown in the upper panel. (C) Power spectra for responses to 4-Hz contrast reversal gratings in all usable channels of the array from one experiment. Log power is presented. (D) Spatial coherence as a function of frequency computed from a space-frequency SVD analysis, averaged over 10 experiments. Shaded region: standard error of the mean.