Fig. 3

VmPFC activity—experiment 2. a VmPFC activity increased at time of decision (top; cluster-corrected z > 2.3; p < 0.05; Supplementary Table 3: GLM-2, contrast 1). Activity increments were prominent in the area removed by the lesion in experiment 1 (bottom). b ROI time course illustrating the effect of decision on BOLD activity. Abscissa indicates time from decision onset and ordinate indicates beta regression coefficients relating the decision event to the BOLD signal. Coordinates for ROI correspond to green circle in a, top (3, 21, 3). (c) Left panel: estimates of each option’s value in each individual animal (M1–M4) and c Right panel: normalized choice values used in two GLM analyses of experiment 2. However, from left panel c it is clear that, prior to normalization, chosen values are usually higher than unchosen values. d Activity in vmPFC (1, 17, −2) covaried with the decision variable guiding choices—difference in subjective value (rather than objective reward amount) between choice taken and choice rejected (chosen value-unchosen value; cluster-corrected z > 2.3; p < 0.05 within 25 mm sphere centered on decision effect in a). The regression coefficients relating the BOLD signal to the difference between chosen and unchosen options at the time of choice is plotted in e and regression coefficients relating the BOLD signal to the value of the chosen option and the unchosen option are plotted separately in f. Difficulty increased, and vmPFC activity increased, when the chosen value was lower or the unchosen value was higher as shown in e and f. g Full summary of lesion location (first row) and of all activity in the frontal lobe positively and negatively related to taking a decision (second row: non-cluster-corrected results; third row: cluster-corrected results) and the decision variable used to guide the decision (chosen–unchosen option value difference; fourth row: non-cluster-corrected results; fifth row: cluster-corrected results). In summary, the results shown in a and d are representative of the pattern of activity found in adjacent regions and no negative decision-related activity and no positive value-related activity was observed within the lesioned areas