Social Cognitive and Affective Neuroscience Advance Access published online on October 20, 2009
Social Cognitive and Affective Neuroscience, doi:10.1093/scan/nsp031
Available alternative incentives modulate anticipatory nucleus accumbens activation
Department of Psychology, Stanford University, Jordan Hall, 450 Serra Mall, Stanford, CA 94305, USA
A reward or punishment can seem better or worse depending on what else might have happened. Little is known, however, about how neural representations of an anticipated incentive might be influenced by the available alternatives. We used event-related FMRI to investigate the activation in the nucleus accumbens (NAcc), while we varied the available alternative incentives in a monetary incentive delay task. Some task blocks included only uncertain gains and losses; others included the same uncertain gains and losses intermixed with certain gains and losses. The availability of certain gains and losses increased NAcc activation for uncertain losses and decreased the difference between uncertain gains and losses. We suggest that this pattern of activation can result from reference point changes across blocks, and that the worst available loss may serve as an important anchor for NAcc activation. These findings imply that NAcc activation represents anticipated incentive value relative to the current context of available alternative gains and losses.
Keywords: context; reference points; reward; nucleus accumbens; fMRI
Correspondence should be addressed to Jeffrey C. Cooper, Department of Psychology, Jordan Hall, 450 Serra Mall, Stanford, CA 94305, USA. Email: jcooper{at}stanford.edu
Received March 6, 2009. Accepted July 16, 2009.