In ACC lesioned rats, similar patterns of firing were observed, with activity tracking the location of the first and second lights (Fig. 2E). During the first light epoch, as in controls, the distribution of indices significantly shifted in the negative direction (Fig. 2F; Wilcoxon; n = 53; µ = −0.11; P < 0.0001); however, in response to the second light, the activity of the majority of neurons did not accurately represent the direction of the response necessary to obtain the reward. The distribution of indices did not significantly shift in the positive direction (Fig. 2G; Wilcoxon; n = 53; µ = 0.0283; P = 0.2743), and the counts of neurons that fired significantly more strongly for actions into the response field did not significantly outnumber those made away from the response field (Fig. 2G, black bars; 6 vs. 11; χ2 = 1.41; P = 0.23). Thus, the population of DMS neurons failed to represent the accurate response after ACC lesions.
