Fear conditioning, pre-pulse inhibition and drug modulation of a short latency startle response measured electromyographically from neck muscles in the rat

Physiol Behav. 1986;36(6):1187-91. doi: 10.1016/0031-9384(86)90499-3.

Abstract

The present study evaluated if startle measured electromyographically in the neck muscles (having a 5 msec latency) would exhibit behavioral and pharmacological plasticity known to alter startle measured in a stabilimeter device. A total of 15 rats were implanted with bilateral EMG electrodes in the dorsal neck muscles and subsequently exposed to a variety of manipulations known to affect the whole-body startle response. The peak-to-peak EMG response that occurred within 10 msec of startle stimulus onset displayed pre-pulse inhibition, enhancement by prior fear conditioning, inhibition by clonidine, and enhancement by strychnine. The data are discussed in terms of modulation of neural transmission along a primary startle-mediating pathway.

Publication types

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

MeSH terms

  • Animals
  • Clonidine / pharmacology*
  • Electromyography
  • Fear / physiology*
  • Male
  • Muscles / physiology*
  • Neck Muscles / physiology*
  • Rats
  • Rats, Inbred Strains
  • Reaction Time / physiology
  • Reflex, Startle / drug effects
  • Reflex, Startle / physiology*
  • Strychnine / pharmacology*

Substances

  • Strychnine
  • Clonidine