Send to

Choose Destination
Eur J Neurosci. 2005 Nov;22(9):2341-6.

Opposing effects of amygdala and orbital prefrontal cortex lesions on the extinction of instrumental responding in macaque monkeys.

Author information

Section on the Neurobiology of Learning and Memory, Laboratory of Neuropsychology, National Institute of Mental Health, NIH, Bethesda, MD 20892, USA.


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.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center