Performance on two fixed-interval schedules in the absence of neocortex in rats

Behav Neurosci. 1990 Oct;104(5):763-77. doi: 10.1037//0735-7044.104.5.763.

Abstract

Rats with complete surgical removal of the neocortex (neodecorticates) were trained, with milk as the reinforcer, on a 40-s fixed-interval (FI-40) schedule, then on an FI-120, and finally reexposed to the FI-40. Like controls, neodecorticates developed and appropriately adjusted their postreinforcement pauses and response distributions and showed scallop-type responding on the FI-120 and a positive correlation between running rate and the preceding postreinforcement pause on both FI-40 schedules but not on the FI-120. On some variables neodecorticates reached asymptotic levels of performance more slowly than controls. Extended training on the first FI-40 did not differentially affect neodecorticates' performance. The results suggest that neodecorticates retain a functional timing mechanism.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arousal / physiology
  • Attention / physiology
  • Brain Mapping
  • Cerebral Cortex / physiology*
  • Conditioning, Operant / physiology*
  • Discrimination Learning / physiology
  • Drinking / physiology
  • Male
  • Mental Recall / physiology*
  • Motivation
  • Motor Activity / physiology
  • Neurons / physiology
  • Rats
  • Reinforcement Schedule*
  • Retention, Psychology / physiology
  • Time Perception / physiology*