Response options and expectations of reward in decision-making: the differential roles of dorsal and rostral anterior cingulate cortex.

This study examined the functional specificity of dorsal anterior cingulate cortex (dACC) and rostral anterior cingulate cortex (rACC)/medial prefrontal cortex (mPFC) regarding two elements of decision-making: the number of available decision options and the level of expected reward. Eighteen healthy participants were trained to recognize the reward value associated with several visual stimuli, and then were presented with groups of two, three, or four of these stimuli and asked to select the object associated with the highest reward. BOLD activation in dACC/dorsomedial frontal cortex (dmFC) was strongly positively associated with increases in the number of decision options but only weakly associated with increases in the level of expected reward. Activation in rACC/mPFC and amygdala was related to increases in the level of expected reward but not increases in the number of decision options. The current results suggest functional specificity with respect to the roles of dACC/dmFC and rACC/mPFC in decision-making.