Accurate timing but increased impulsivity following excitotoxic lesions of the subthalamic nucleus

Neurosci Lett. 2008 Aug 1;440(2):176-80. doi: 10.1016/j.neulet.2008.05.071. Epub 2008 May 24.


Several lines of evidence have implicated the subthalamic nucleus (STN) in behaviors that require precise temporal control. In order to investigate this possibility further, we trained rats to perform a peak-interval (PI) timing task [S. Roberts, Isolation of an internal clock, J. Exp. Psychol. Anim. B 7 (1981) 242-268] with two durations (10 s and 40 s), and then lesioned the STN by microinjection of ibotenic acid. Lesioned animals were able to maintain precise temporal control, yet were unable to inhibit operant responses late in the trial, at times that were unlikely to yield reinforcement. These results indicate the involvement of the STN in impulsive or perseverative response inhibition, but not in temporal processing.

MeSH terms

  • Animals
  • Behavior, Animal / drug effects
  • Behavior, Animal / physiology
  • Conditioning, Operant / drug effects
  • Conditioning, Operant / physiology
  • Ibotenic Acid / administration & dosage
  • Ibotenic Acid / toxicity
  • Impulsive Behavior / physiopathology*
  • Impulsive Behavior / psychology
  • Inhibition, Psychological
  • Male
  • Motor Activity / drug effects
  • Motor Activity / physiology*
  • Rats
  • Rats, Sprague-Dawley
  • Reaction Time / drug effects
  • Reaction Time / physiology*
  • Reinforcement, Psychology
  • Subthalamic Nucleus / drug effects
  • Subthalamic Nucleus / physiology*


  • Ibotenic Acid