Recovery of function after brain damage: severe and chronic disruption by diazepam

Brain Res. 1986 Jul 30;379(1):104-11. doi: 10.1016/0006-8993(86)90261-1.


Following unilateral damage to the anterior-medial region of the neocortex (AMC) in rats a sensory asymmetry appeared, but recovered within a week. In a separate group of rats with AMC lesions daily 3-week exposure to diazepam (Valium, 5 mg/kg) beginning 12 h after surgery caused recovery to be delayed indefinitely. The efficiency and speed (as opposed to symmetry) of behavior was not impaired. More than 9 weeks after discontinuation of diazepam (12 weeks postsurgery), recovery was still not apparent. Postmortem analysis ruled out lesion size as a contributing factor. In a second experiment undrugged animals with AMC lesions were allowed to recover for at least 3 weeks before being exposed to diazepam. These animals showed only a transient (2-day) reinstatement of asymmetry despite continuous drug treatment. We conclude that important mechanisms serving recovery of function may be vulnerable during a short period soon after brain damage.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Brain Injuries / physiopathology*
  • Diazepam / toxicity*
  • Functional Laterality / physiology
  • Male
  • Nerve Crush
  • Nerve Regeneration / drug effects*
  • Neurons, Afferent / drug effects
  • Neurons, Afferent / pathology
  • Postoperative Period
  • Rats
  • Rats, Inbred Strains
  • Reaction Time / drug effects
  • Somatosensory Cortex / drug effects
  • Somatosensory Cortex / pathology
  • Somatosensory Cortex / physiopathology


  • Diazepam