title: Basolateral amygdala lesions facilitate reward choices after negative feedback in rats.
abstract: The orbitofrontal cortex (OFC) and basolateral amygdala (BLA) constitute part of a neural circuit important for adaptive, goal-directed learning. One task measuring flexibility of response to changes in reward is discrimination reversal learning. Damage to OFC produces well documented impairments on various forms of reversal learning in rodents, monkeys, and humans. Recent reports show that BLA, though highly interconnected with OFC, may be differentially involved in reversal learning. In the present experiment, we compared the effects of bilateral, ibotenic acid lesions of OFC or BLA (or SHAM) on visual discrimination and reversal learning. Specifically, we used pairwise visual discrimination methods, as is commonly administered in non-human primate studies, and analyzed how animals use positive and negative trial-by-trial feedback, domains not previously explored in a rat study. As expected, OFC lesions displayed significantly slower reversal learning than SHAM and BLA rats across sessions. Rats with BLA lesions, conversely, showed facilitated reversal learning relative to SHAM and OFC groups. Furthermore, a trial-by-trial analysis of the errors committed showed the BLA group benefited more from incorrectly performed trials (or negative feedback) on future choices than either SHAM or OFC rats. This provides evidence that BLA and OFC are involved in updating responses to changes in reward contingency and that the roles are distinct. Our results are discussed in relation to a competitive framework model for OFC and BLA in reward processing.
authors: Laboratory of Cognitive Neuroscience, Department of Psychology, California State University, Los Angeles, Los Angeles, California 90032, USA. aizquie@calstatela.edu
authors: Alicia
authors: A
authors: Izquierdo
authors: Chelsi
authors: C
authors: Darling
authors: Nic
authors: N
authors: Manos
authors: Hilda
authors: H
authors: Pozos
authors: Charissa
authors: C
authors: Kim
authors: Serena
authors: S
authors: Ostrander
authors: Victor
authors: V
authors: Cazares
authors: Haley
authors: H
authors: Stepp
authors: Peter H
authors: PH
authors: Rudebeck
mesh_terms: D000679:Amygdala / Q000293:injuries / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D002755:Choice Behavior / Q000502:physiology*; D003216:Conditioning, Operant / Q000502:physiology*; D004193:Discrimination Learning / Q000187:drug effects / Q000502:physiology; D018690:Excitatory Amino Acid Agonists / Q000633:toxicity; D005246:Feedback / Q000187:drug effects; D005518:Food Preferences / Q000187:drug effects / Q000502:physiology; D007051:Ibotenic Acid / Q000633:toxicity; D008297:Male; D010775:Photic Stimulation; D017397:Prefrontal Cortex / Q000293:injuries / Q000502:physiology; D051381:Rats; D020318:Rats, Long-Evans; D012193:Reversal Learning; D012201:Reward
chemical_list: D018690:Excitatory Amino Acid Agonists; D007051:Ibotenic Acid