Electrical stimulation of medial prefrontal cortex reduces conditioned fear in a temporally specific manner

Behav Neurosci. 2004 Apr;118(2):389-94. doi: 10.1037/0735-7044.118.2.389.


The authors recently showed that extinction of auditory fear conditioning leads to potentiation of tone-evoked activity of neurons in the infralimbic (IL) subregion of the medial prefrontal cortex, suggesting that IL inhibits fear after extinction (M. R. Milad, & G. J. Quirk, 2002). In support of this finding, pairing conditioned tones with brief (300-ms) electrical stimulation of IL reduces conditioned freezing. The present study showed that IL stimulation inhibits freezing if given 0.1 s after tone onset (the latency of tone-evoked responses) but has no effect if given either 1 s before or 1 s after tone onset. This suggests that IL gates the response of downstream structures such as the amygdala to fear stimuli.

Publication types

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

MeSH terms

  • Animals
  • Conditioning, Psychological*
  • Electric Stimulation / instrumentation
  • Electrodes, Implanted
  • Extinction, Psychological
  • Fear*
  • Mental Recall
  • Prefrontal Cortex / physiology*
  • Rats
  • Reinforcement Schedule
  • Time Factors