Figure 8.

Extinction animals exhibit significantly higher gamma coherence during fear conditioning and extinction. A, Spectral graphs showing coherence normalized relative to baseline displaying levels of synchronization across frequencies in the extinction and control animals. Note the sustained level of low and high gamma coherence during extinction in experimental animals compared with water control animals. B–D, Histograms showing normalized binned coherence at theta and low and high gamma frequencies. B, There was a moderate increase in theta coherence throughout learning in the experimental group. C, D, Low (C) and high (D) gamma coherence increased during extinction and postext sessions in the experimental animals compared with controls. Bars represent means ± SEM, *p < 0.05.