Thu, 21 Aug 2008 15:32:20 BST CiteULike: oamg Friston http://www.citeulike.org/user/oamg/author/Friston CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/oamg/article/1325561 <i>Nature, Vol. 378, No. 6553. (November 1995), pp. 180-182.</i> Dopaminergic modulation of impaired cognitive activation in the anterior cingulate cortex in schizophrenia RJ Dolan P Fletcher CD Frith KJ Friston RSJ Frackowiak PM Grasby doi:10.1038/378180a0 Nature, Vol. 378, No. 6553. (November 1995), pp. 180-182. 2007-05-24T17:51:22-00:00 1995 Nature 378 6553 180 182 anterior_cingulate_cortex dopamine human pet schizophrenia http://www.citeulike.org/user/oamg/article/1325557 <i>J. Neurosci., Vol. 20, No. 16. (15 August 2000), pp. 6159-6165.</i><br /><br />Reward is one of the most important influences shaping behavior. Single-unit recording and lesion studies in experimental animals have implicated a number of regions in response to reinforcing stimuli, in particular regions of the extended limbic system and the ventral striatum. In this experiment, functional neuroimaging was used to assess neural response within human reward systems under different psychological contexts. Nine healthy volunteers were scanned using functional magnetic resonance imaging during the performance of a gambling task with financial rewards and penalties. We demonstrated neural sensitivity of midbrain and ventral striatal regions to financial rewards and hippocampal sensitivity to financial penalties. Furthermore, we show that neural responses in globus pallidus, thalamus, and subgenual cingulate were specific to high reward levels occurring in the context of increasing reward. Responses to both reward level in the context of increasing reward and penalty level in the context of increasing penalty were seen in caudate, insula, and ventral prefrontal cortex. These results demonstrate dissociable neural responses to rewards and penalties that are dependent on the psychological context in which they are experienced. Dissociable Neural Responses in Human Reward Systems Rebecca Elliott Karl Friston Raymond Dolan J. Neurosci., Vol. 20, No. 16. (15 August 2000), pp. 6159-6165. 2007-05-24T17:50:00-00:00 2000 J. Neurosci. 20 16 6159 6165 fmri globus_pallidus hippocampus penalties rewards striatum http://www.citeulike.org/user/oamg/article/488875 <i>Science, Vol. 304, No. 5669. (16 April 2004), pp. 452-454.</i><br /><br />Instrumental conditioning studies how animals and humans choose actions appropriate to the affective structure of an environment. According to recent reinforcement learning models, two distinct components are involved: a "critic," which learns to predict future reward, and an "actor," which maintains information about the rewarding outcomes of actions to enable better ones to be chosen more frequently. We scanned human participants with functional magnetic resonance imaging while they engaged in instrumental conditioning. Our results suggest partly dissociable contributions of the ventral and dorsal striatum, with the former corresponding to the critic and the latter corresponding to the actor. Dissociable roles of ventral and dorsal striatum in instrumental conditioning. J O'Doherty P Dayan J Schultz R Deichmann K Friston RJ Dolan doi:10.1126/science.1094285 Science, Vol. 304, No. 5669. (16 April 2004), pp. 452-454. 2006-02-01T20:02:54-00:00 2004 Science 1095-9203 304 5669 452 454 dorsal_striatum instrumental_conditioning ventral_striatum