The ontogeny of fear-potentiated startle: Effects of earlier-acquired fear memories

School of Psychology, University of New South Wales, Sydney, NSW, Australia.
Behavioral Neuroscience (Impact Factor: 3.25). 10/2007; 121(5):1053-62. DOI: 10.1037/0735-7044.121.5.1053
Source: PubMed

ABSTRACT 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.

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