Orbitofrontal cortex mediates outcome encoding in pavlovian but not instrumental conditioning.

@article{citeulike:1283982, abstract = {Previous studies have implicated the orbitofrontal cortex (OFC) in outcome encoding. However, it remains unknown whether the OFC is selectively involved in pavlovian stimulus-outcome learning or whether it also contributes to instrumental action-outcome learning. In experiment 1, we investigated this issue by assessing the effects of bilateral lesions of the OFC on the sensitivity of instrumental lever press performance to a reduction in the incentive value of the training outcome (a test of action-outcome encoding) and to outcome-specific pavlovian-instrumental transfer (a test of stimulus-outcome encoding). We found that post-training lesions of the OFC did not affect instrumental outcome devaluation, but abolished the transfer effect. Interestingly, lesions made before training had no effect on either task. In experiment 2, we explored the involvement of the OFC in updating stimulus-outcome associations after the underlying contingency, or predictive relationship, between these two events has been degraded. Shams displayed clear contingency learning, withholding conditioned responding to a stimulus that no longer reliably predicted its outcome while continuing to respond to a control stimulus that remained a good predictor of a different outcome. In contrast, OFC-lesioned rats stopped responding to both stimuli, regardless of their predictive status. Together, these findings suggest that the OFC supports outcome encoding in pavlovian, but not instrumental conditioning.}, address = {Department of Psychology and the Brain Research Institute, University of California, Los Angeles, California 90095-1563, USA. sostlund@ucla.edu}, author = {Ostlund, S. B. and Balleine, B. W. }, citeulike-article-id = {1283982}, doi = {http://dx.doi.org/10.1523/JNEUROSCI.5443-06.2007}, issn = {1529-2401}, journal = {J Neurosci}, keywords = {cause\_and\_effect, instrumental\_conditioing, orbitofrontal\_cortex, pavolvian\_conditioning, reinforcement\_learning}, month = {May}, number = {18}, pages = {4819--4825}, posted-at = {2007-06-01 15:50:25}, priority = {2}, title = {Orbitofrontal cortex mediates outcome encoding in pavlovian but not instrumental conditioning.}, url = {http://dx.doi.org/10.1523/JNEUROSCI.5443-06.2007}, volume = {27}, year = {2007} }

TY - JOUR ID - citeulike:1283982 L3 - citeulike-article-id:1283982 TI - Orbitofrontal cortex mediates outcome encoding in pavlovian but not instrumental conditioning. JF - J Neurosci VL - 27 IS - 18 SP - 4819 EP - 4825 AD - Department of Psychology and the Brain Research Institute, University of California, Los Angeles, California 90095-1563, USA. sostlund@ucla.edu SN - 1529-2401 N2 - Previous studies have implicated the orbitofrontal cortex (OFC) in outcome encoding. However, it remains unknown whether the OFC is selectively involved in pavlovian stimulus-outcome learning or whether it also contributes to instrumental action-outcome learning. In experiment 1, we investigated this issue by assessing the effects of bilateral lesions of the OFC on the sensitivity of instrumental lever press performance to a reduction in the incentive value of the training outcome (a test of action-outcome encoding) and to outcome-specific pavlovian-instrumental transfer (a test of stimulus-outcome encoding). We found that post-training lesions of the OFC did not affect instrumental outcome devaluation, but abolished the transfer effect. Interestingly, lesions made before training had no effect on either task. In experiment 2, we explored the involvement of the OFC in updating stimulus-outcome associations after the underlying contingency, or predictive relationship, between these two events has been degraded. Shams displayed clear contingency learning, withholding conditioned responding to a stimulus that no longer reliably predicted its outcome while continuing to respond to a control stimulus that remained a good predictor of a different outcome. In contrast, OFC-lesioned rats stopped responding to both stimuli, regardless of their predictive status. Together, these findings suggest that the OFC supports outcome encoding in pavlovian, but not instrumental conditioning. KW - cause_and_effect KW - instrumental_conditioing KW - orbitofrontal_cortex KW - pavolvian_conditioning KW - reinforcement_learning AU - Ostlund, SB AU - Balleine, BW PY - 2007/05/02/ UR - http://dx.doi.org/10.1523/JNEUROSCI.5443-06.2007 ER -