Figure 6.

vlOFC, but not BLA, inhibition impairs adjustment to stimulus-based reversals as measured by probability correct. A, B, Trial structure (A) and timeline (B) of the stimulus-based task. Rats were first surgerized with either hM4Di DREADDs or eGFP null virus on a CaMKII promoter. Rats were allowed to recover for 1 week before testing on a stimulus- or action-based reversal learning task. C, Initial learning of a rewarded stimulus, presented pseudorandomly on the left or right side of the touchscreen for eGFP (top), vlOFC hM4Di (middle), and BLA hM4Di (bottom). D, Plots of accuracy around reversals were restricted to include only animals that reached greater than 50% running window average for the last 100 trials in initial discrimination. Rats were always tested on a deterministic schedule before a probabilistic one. Shown are subsequent deterministic (100/0) and probabilistic (90/10) reversal “transitions,” three sessions before and after each reversal. Drug order was counterbalanced such that on R2 and R4 animals received VEH if they were administered CNO first on R1 and R3 and vice versa. Chemogenetic inhibition of vlOFC abolishes changes in probability correct over the last three (pre-) and first three (post-) reversal sessions, indicating impaired adjustments to reversals. In contrast, BLA inhibition had no clear impact on reversal learning. There was also no effect of CNO in eGFP group learning. **p < 0.01 different than eGFP following ANOVA of pre-/post-difference. vlOFC inhibition abolished learning after the first stimulus-based reversal (Fig. 7), but did not significantly impair adjustment around action-based probabilistic reversal as following BLA inhibition (Fig. 8).