title: The role of ventral frontostriatal circuitry in reward-based learning in humans.
abstract: This study examined changes in behavior and neural activity with reward learning. Using an event-related functional magnetic resonance imaging paradigm, we show that the nucleus accumbens, thalamus, and orbital frontal cortex are each sensitive to reward magnitude, with the accumbens showing the greatest discrimination between reward values. Mean reaction times were significantly faster to cues predicting the greatest reward and slower to cues predicting the smallest reward. This behavioral change over the course of the experiment was paralleled by a shift in peak in accumbens activity from anticipation of the reward (immediately after the response), to the cue predicting the reward. The orbitofrontal and thalamic regions peaked in anticipation of the reward throughout the experiment. Our findings suggest discrete functions of regions within basal ganglia thalamocortical circuitry in adjusting behavior to maximize reward.
authors.affiliation: Sackler Institute, Weill Medical College of Cornell University, New York, New York 10021, USA. adg2006@med.cornell.edu
authors.forename: Adriana
authors.initials: A
authors.lastname: Galvan
authors.forename: Todd A
authors.initials: TA
authors.lastname: Hare
authors.forename: Matthew
authors.initials: M
authors.lastname: Davidson
authors.forename: Julie
authors.initials: J
authors.lastname: Spicer
authors.forename: Gary
authors.initials: G
authors.lastname: Glover
authors.forename: B J
authors.initials: BJ
authors.lastname: Casey
mesh_terms: D000328:Adult; D003342:Corpus Striatum / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000502:physiology*; D006801:Humans; D007858:Learning / Q000502:physiology*; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009415:Nerve Net / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time / Q000502:physiology; D012201:Reward