title: Dorsal striatum is necessary for stimulus-value but not action-value learning in humans.
abstract: Several lines of evidence implicate the striatum in learning from experience on the basis of positive and negative feedback. However, the necessity of the striatum for such learning has been difficult to demonstrate in humans, because brain damage is rarely restricted to this structure. Here we test a rare individual with widespread bilateral damage restricted to the dorsal striatum. His performance was impaired and not significantly different from chance on several classic learning tasks, consistent with current theories regarding the role of the striatum. However, he also exhibited remarkably intact performance on a different subset of learning paradigms. The tasks he could perform can all be solved by learning the value of actions, while those he could not perform can only be solved by learning the value of stimuli. Although dorsal striatum is often thought to play a specific role in action-value learning, we find surprisingly that dorsal striatum is necessary for stimulus-value but not action-value learning in humans.
authors.affiliation: 1 Department of Psychology, University of Pennsylvania, 3720 Walnut St., Philadelphia, PA 19104, USA.
authors.forename: Khoi
authors.initials: K
authors.lastname: Vo
authors.affiliation: 2 Wellcome Trust Centre for Neuroimaging, UCL, London WC1N 3BG, UK, and Max Planck UCL Centre for Computational Psychiatry and Ageing Research, London WC1B 5EH, UK.
authors.forename: Robb B
authors.initials: RB
authors.lastname: Rutledge
authors.affiliation: 3 Department of Neurology, University of Pennsylvania, 3 West Gates, 3400 Spruce St., Philadelphia, PA 19104, USA.
authors.forename: Anjan
authors.initials: A
authors.lastname: Chatterjee
authors.affiliation: 1 Department of Psychology, University of Pennsylvania, 3720 Walnut St., Philadelphia, PA 19104, USA kable@psych.upenn.edu.
authors.forename: Joseph W
authors.initials: JW
authors.lastname: Kable
mesh_terms: D001925:Brain Damage, Chronic / Q000175:diagnosis / Q000503:physiopathology*; D001931:Brain Mapping; D003342:Corpus Striatum / Q000503:physiopathology*; D006801:Humans; D007858:Learning / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D013647:Task Performance and Analysis
keywords: action-value; reinforcement learning; stimulus-value; striatum