Whereas Figure 7 showed spike-field coupling, here we detail power. There was elevated power between 1 and 12 Hz on post-error trials in a) control sessions and b) with medial frontal cortex inactivated. Power was more similar between post-error and post-correct trials when medial frontal cortex was inactivated. c) Direct comparison of differential post-error vs. post-correct trials on control sessions vs sessions with medial frontal cortex inactivated. Differential power between post-correct and post-error trials diminished in medial frontal inactivation sessions. Black contours indicate significant differences via a t-test between control and medial frontal inactivation sessions (p<0.05).