Effects of selective excitotoxic lesions of the nucleus accumbens core, anterior cingulate cortex, and central nucleus of the amygdala on autoshaping performance in rats

Behav Neurosci. 2002 Aug;116(4):553-67. doi: 10.1037//0735-7044.116.4.553.

Abstract

The nucleus accumbens core (AcbC), anterior cingulate cortex (ACC), and central nucleus of the amygdala (CeA) are required for normal acquisition of tasks based on stimulus-reward associations. However, it is not known whether they are involved purely in the learning process or are required for behavioral expression of a learned response. Rats were trained preoperatively on a Pavlovian autoshaping task in which pairing a visual conditioned stimulus (CS+) with food causes subjects to approach the CS+ while not approaching an unpaired stimulus (CS-). Subjects then received lesions of the AcbC, ACC, or CeA before being retested. AcbC lesions severely impaired performance; lesioned subjects approached the CS+ significantly less often than controls, failing to discriminate between the CS+ and CS-. ACC lesions also impaired performance but did not abolish discrimination entirely. CeA lesions had no effect on performance. Thus, the CeA is required for learning, but not expression, of a conditioned approach response, implying that it makes a specific contribution to the learning of stimulus-reward associations.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amygdala / pathology
  • Amygdala / physiology*
  • Animals
  • Cerebral Cortex / pathology
  • Cerebral Cortex / physiology*
  • Conditioning, Classical
  • Discrimination Learning*
  • Male
  • Nucleus Accumbens / pathology
  • Nucleus Accumbens / physiology*
  • Rats