The ontogeny of fear-potentiated startle: effects of earlier-acquired fear memories.
Research has shown that learned fear emerges in a response-specific sequence. For example, freezing is observed at a younger age than is potentiated startle (P. Hunt & B. A. Campbell, 1997). The present study shows that the age at which a specific learned fear response emerges is influenced by the animal's early experiences. Specifically, fear potentiation of startle emerges earlier in development if the rat is given prior fear conditioning to a different stimulus. Some constraints of this "facilitation" effect are determined in follow-up experiments. This facilitation effect may provide a novel way of testing the development of the neural circuits underlying learned fear.
Yap
Carol S L
CS
School of Psychology, University of New South Wales, Sydney, NSW, Australia. c.yap@student.unsw.edu.au
Richardson
Rick
R
D000161:Acoustic Stimulation; D000375:Aging / Q000523:psychology*; D000818:Animals; D003213:Conditioning, Psychological; D004597:Electroshock; D005239:Fear / Q000523:psychology*; D008297:Male; D009812:Odorants; D051381:Rats; D017207:Rats, Sprague-Dawley; D013216:Reflex, Startle / Q000502:physiology*; D012903:Smell