Figure 7.

Firing rate dynamics before and after the task change. The figure shows normalized firing rates for individual cells (blue dots) recorded during identical behaviors. Firing rates for each cell was measured in its preferred path during the 10 trials before and after a task change (indicated by the vertical dotted lines). Only trials with more than five firing rate data points are included. The solid red line shows the moving average of the mean Z score firing rate; the dashed red lines show 95% confidence intervals. The inset shows the mean Z score firing rates (±SD) for all cells before the task change (SP) and during learning before criterion [learn; inset asterisk (*) shows Student's t test, p < 0.05]. A, Firing rate on preferred paths declined immediately after the task changed across all reversals [the asterisk (*) indicates significant decline compared with before the task change, one-way Student's t test, p < 0.05]. B, A similar decline in firing rates occurred in reversal 1. C, A mean firing rate reduction occurred during all switches (inset), but the trialwise firing rate change was smaller. D, The firing rate did not change during switch 1. The analysis shows that even when the rat followed the same path, OFC neuronal activity declined in correlation with falling reward probability when the task was changed.