The central amygdala is involved in conditioning but not in retention of active and passive shock avoidance in male rats

Behav Neural Biol. 1993 Mar;59(2):143-9. doi: 10.1016/0163-1047(93)90873-g.

Abstract

The present study was designed to further characterize the involvement of the central amygdaloid nucleus (CEA) in the conditioning and the retention of both active and passive stress-related behaviors. Active shock avoidance was investigated in a shuttle-box. CEA-lesioned and sham-operated animals received 30 trials on 2 consecutive days. During the first day of conditioning, the CEA-lesioned animals failed to learn to avoid, but on the second day these rats showed avoidance behavior that was comparable to the sham-lesioned ones. When lesioned animals received a total of 60 trials on 1 day, they failed to show avoidance, suggesting deficits in acquisition performance but presence of latent learning following CEA lesioning. However, the retention response, which was studied by lesioning the CEA between a 2-day avoidance training and a retention test, was unaffected. Stress-related learning was also studied in a test of passive avoidance of a previously received single, inescapable electric footshock. When the lesion was placed before the single learning trial, the retention of the response was absent. However, CEA-lesioning after the learning trial revealed no differences between the CEA-lesioned and sham-lesioned animals. In conclusion, these results demonstrate that the CEA is involved in the conditioning rather than retention of both active and passive shock avoidance responses.

MeSH terms

  • Amygdala / physiology*
  • Amygdala / physiopathology
  • Animals
  • Avoidance Learning*
  • Behavior, Animal
  • Conditioning, Psychological*
  • Discrimination Learning
  • Male
  • Neurosecretory Systems
  • Neurotransmitter Agents
  • Rats
  • Rats, Wistar
  • Retention, Psychology*

Substances

  • Neurotransmitter Agents