Monday, March 26, 2012
Neural and Behavioral Investigations of Social Reward Processing
Despite an extensive literature on the neural substrates of reward, relatively little is known about how social interactions modify decision-making.Here I present three experiments that examine the neural basis of social reward processing both in neurotypicals and individuals with autism spectrum disorder (ASD), a neuropsychiatric syndrome associated with social cognition impairments. Using functional magnetic resonance imaging (fMRI), I recorded brain activity during a probabilistic reward learning task with either social (smiling/frowning faces) or monetary (gaining/losing money) rewards. I found substantial overlap in the neural circuitry associated with social and non-social reward processing, suggesting that social rewards are processed similarly to other types of rewards. In contrast, individuals with ASD showed behavioral impairments in social reward processing, both in probabilistic reward learning and in an ecologically valid charitable donation task. Exploratory neuroimaging in ASD showed hypoactivation of key reward areas during decision-making. Taken together, these findings support the idea of a common neural currency in decision-making but also suggests the construction of accurate social reward value signals may rely on recruitment of additional social processing areas.