title: Opposing effects of amygdala and orbital prefrontal cortex lesions on the extinction of instrumental responding in macaque monkeys.
abstract: Extinction is a well-known behavioural phenomenon that allows organisms to respond flexibly to a changing environment. Although recent work implicates the amygdala and orbital prefrontal cortex (PFo) in extinction of Pavlovian conditioned fear and aversion, much less is known about the neural bases of instrumental extinction. To explore the contribution of the macaque amygdala to flexible responding in the face of changing reward contingency, we tested the effects of selective, excitotoxic lesions of the amygdala on extinction of an instrumental response. For comparison, we evaluated the effects of ablation of PFo on the same task. Amygdala lesions facilitated the extinction of instrumental responses, whereas lesions of PFo had the opposite effect.
authors.affiliation: Section on the Neurobiology of Learning and Memory, Laboratory of Neuropsychology, National Institute of Mental Health, NIH, Bethesda, MD 20892, USA.
authors.forename: Alicia
authors.initials: A
authors.lastname: Izquierdo
authors.forename: Elisabeth A
authors.initials: EA
authors.lastname: Murray
mesh_terms: D000679:Amygdala / Q000187:drug effects / Q000293:injuries / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal; D003214:Conditioning, Classical / Q000502:physiology*; D018690:Excitatory Amino Acid Agonists / Q000633:toxicity; D005108:Extinction, Psychological / Q000502:physiology*; D007051:Ibotenic Acid / Q000633:toxicity; D008253:Macaca mulatta; D008297:Male; D017397:Prefrontal Cortex / Q000293:injuries / Q000502:physiology*; D012201:Reward; D013396:Suction / Q000379:methods
chemical_list: D018690:Excitatory Amino Acid Agonists; D007051:Ibotenic Acid