Neurally reconstructing expected utility

While the concept of "expected utility" informs many theories of decision making, little is known about whether and how the human brain might compute this quantity. This article reviews a series of functional magnetic resonance imaging (FMRI) experiments designed to localize brain regions that respond in anticipation of increasing amounts of monetary incentives. These studies collectively suggest that anticipation of increasing monetary gains activates a subcortical region of the ventral striatum in a magnitude-proportional manner. This ventral striatal activation is not evident during anticipation of losses. Actual gain outcomes instead activate a region of the mesial prefrontal cortex. During anticipation of gain, ventral striatal activation is accompanied by feelings characterized by increasing arousal and positive valence. These findings affirm the role of emotion in the anticipation of incentives, and may provide an initial step towards a neural reconstruction of expected utility. (c) 2005 Elsevier Inc. All rights reserved.