Animal Learning & Behavior

, Volume 20, Issue 2, pp 177–186

Fear potentiation of the acoustic startle reflex using noises of various spectral frequencies as conditioned stimuli

  • Serge Campeau
  • Michael Davis
Article

DOI: 10.3758/BF03200415

Cite this article as:
Campeau, S. & Davis, M. Animal Learning & Behavior (1992) 20: 177. doi:10.3758/BF03200415

Abstract

The effectiveness of noise of various intensities and frequencies in modulating the amplitude of the acoustic startle reflex was evaluated, as a preliminary test of the capacity of these noises to produce consistent and reliable fear-potentiated startle in rats. It was determined that bands of noise containing high frequencies (greater than 10 kHz) tend to unconditionally reduce acoustic startle responses, probably by masking the high-frequency startle-eliciting stimulus. Noise containing high frequencies produced reliable fear-potentiated startle only when its estimated unconditioned startle suppression was subtracted from the enhancement obtained after pairing it with footshocks. Noises devoid of high frequencies produced modest-unconditioned startle enhancements and the most robust and reliable fear-potentiated startle when they were paired with footshocks. A nonmonotonic relationship between training shock intensity and the level of fear-potentiated startle was also exhibited when a low-frequency noise was used as a conditioned stimulus, a finding consistent with previous studies in which a visual stimulus was used. Finally, a differential Pavlovian conditioning procedure indicated that rats could readily discriminate between two different low-frequency bands of noise. The outcome of these experiments indicates that it is easier to employ low-frequency bands of noise to obtain auditory fear-potentiated startle with high-frequency startle-eliciting stimuli.

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Copyright information

© Psychonomic Society, Inc. 1992

Authors and Affiliations

  • Serge Campeau
    • 1
    • 2
  • Michael Davis
    • 1
    • 2
  1. 1.Department of PsychiatryYale University School of MedicineNew Haven
  2. 2.Ribicoff Research Facilities of the Connecticut Mental Health CenterNew Haven