FIG. 3.

Activation in putamen by expectation of reward. A: compared with neutral stimulus B−, reward-predicting stimulus A+ activated the putamen bilaterally. Activations extended into the globus pallidus and the right insula. The cortical and cerebellar activations were not expected a priori and did not survive whole brain correction. B and C: event-related time courses of responses to stimuli A+ and B− averaged across subjects within the left (−18/3/−3; B) and right (18/3/−6; C) ventral putamen. Stimuli occurred at time = 0 and were displayed for 3 s. A+ but not B− was followed by reward at the end of the 3-s stimulus duration. This analysis was performed over all subjects, irrespective of behavioral blocking.