Group-level Coherograms within the 0 to 50 Hz frequency range computed from 1-minute segments prior to surgical stimulation. A. Median coherogram during baseline showing a relative absence of coherence in theta, alpha, beta and gamma frequency bands (n = 12). B. Median coherogram during gamma burst. Compared to baseline, there is increased coherence in slow, delta, theta, and gamma frequency bands (n = 12). C. Median coherogram during beta/gamma stable. Compared to baseline, there is increased coherence in theta and gamma frequency bands (n = 11).