Amygdala-prefrontal cortical circuitry regulates effort-based decision making

The basolateral amygdala (BLA) and the anterior cingulate cortex (ACC) region of the prefrontal cortex form an interconnected neural circuit that may mediate certain types of decision-making processes. The present study assessed the role of this pathway in effort-based decision making using a cost-benefit T-maze task. Rats were given a choice of obtaining a high reward by climbing a 30-cm barrier in 1 arm (4 pellets; high-reward [HR] arm) or a small reward in the other arm with no barrier (2 pellets; low-reward [LR] arm). In Experiment 1, bilateral inactivation of the BLA via infusion of bupivacaine impaired decision making, reducing the preference for the HR arm. This effect was not due to spatial or motor deficits because BLA inactivation did not alter behavior when the amount of effort required to obtain either reward was equalized by placing a 2nd barrier in the LR arm. In Experiment 2, disconnection between the BLA and ACC, entailing a unilateral BLA inactivation combined with a contralateral ACC inactivation also impaired decision making. These data suggest that the serial transfer of information between the BLA and ACC guides response selection when evaluating the value of an expected outcome relative to the costs of performing a particular action.