Event Abstract Back to Event Hemispheric dissociation of instrumental learning Stefano Palminteri1*, Giulia Serra1, Thomas Boraud2, Marie-Laure Welter1, Luc Mallet1 and Mathias Pessiglione1 1 Universite Pierre et Marie Curie, CR-ICM, INSERM UMRS 975, France 2 CNRS UMR 5227, Basal Gang team, France A standard computational solution to instrumental learning consists in updating action values according to reward prediction errors. Little is known however about how action values are represented in the human brain: are they integrated into a single center or distributed over different areas? Our hypothesis is that action values are topographically represented in relation to sensorimotor somatotopy. To dissociate the values of actions that would specifically engage either the left or right hemisphere, we presented visual cues on the left and right of a central fixation cross, and asked subjects to respond with either their left or right hand. The cues were associated with rewards through probabilistic contingencies that subjects had to learn so as to maximize payoff. In a functional neuroimaging experiment, we found that the values of left and right actions were specifically expressed in the controlateral ventral prefrontal cortex. Brain hemispheres thus appeared to specifically track the values of actions under their respective control. A subsequent prediction is that the learning processes implemented in the two hemispheres could be modulated independently. We tested this prediction in a second experiment, by subjecting patients with Parkinson's disease to the same instrumental learning task. Patients were tested under unilateral stimulation of the subthalamic nucleus, once on the left and once on the right. We found that learning curves were selectively enhanced on the side controlateral to the stimulation. We conclude that instrumental learning is dissociable between brain hemispheres, in terms of both neuronal representations and behavioral responses. Conference: Computations, Decisions and Movement, Giessen, Germany, 19 May - 22 May, 2010. Presentation Type: Poster Presentation Topic: Posters Citation: Palminteri S, Serra G, Boraud T, Welter M, Mallet L and Pessiglione M (2010). Hemispheric dissociation of instrumental learning. Front. Comput. Neurosci. Conference Abstract: Computations, Decisions and Movement. doi: 10.3389/conf.fnins.2010.01.00015 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 01 Feb 2010; Published Online: 01 Feb 2010. * Correspondence: Stefano Palminteri, Universite Pierre et Marie Curie, CR-ICM, INSERM UMRS 975, Paris, France, stefano.palminteri@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Stefano Palminteri Giulia Serra Thomas Boraud Marie-Laure Welter Luc Mallet Mathias Pessiglione Google Stefano Palminteri Giulia Serra Thomas Boraud Marie-Laure Welter Luc Mallet Mathias Pessiglione Google Scholar Stefano Palminteri Giulia Serra Thomas Boraud Marie-Laure Welter Luc Mallet Mathias Pessiglione PubMed Stefano Palminteri Giulia Serra Thomas Boraud Marie-Laure Welter Luc Mallet Mathias Pessiglione Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.