Latency of the two-way avoidance response in rats: inhibition of delay

Acta Neurobiol Exp (Wars). 1993;53(4):535-45.


Avoidance and escape latencies were examined in 24 rats trained in two-way avoidance response to auditory and visual conditioned stimuli (CS). In rats trained with darkness CS the escape latencies decreased within the first 50-trial session but later were stable over the course of nine sessions. Avoidance latencies shortened within sessions as the response-eliciting properties of the conditioned stimuli increased. On the contrary, median daily avoidance latencies lengthened during training. Training with the more salient auditory stimulus resulted in a decrease in the probability of avoidance responses early in the CS-US interval, reflecting the development of inhibition of delay. Acquired inhibition of delay was eliminated by an increase in the fear-inducing properties of situational cues. When presented in a compound, the less salient darkness stimulus was fully overshadowed by the noise stimulus.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Avoidance Learning / physiology*
  • Escape Reaction / physiology
  • Male
  • Neural Inhibition / physiology*
  • Rats
  • Rats, Wistar
  • Reaction Time