The Pavlovian journal of biological science : official journal of the Pavlovian

, Volume 17, Issue 4, pp 204-214

First online:

Species-specific defense reactions and avoidance learning

An evaluative review
  • Mary CrawfordAffiliated withWest Chester State College
  • , Fred A. MastersonAffiliated withUniversity of Delaware

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Bolles (1970) proposed a theory of avoidance learning, the species-specific defense reaction (SSDR) hypothesis, which emphasized innate constraints on the response repertoire of rats in aversive situations and minimized the role of reinforcement in avoidance learning. The present paper describes Bolles’ (1970, 1971, 1972, 1975, 1978) development of SSDR theory and reviews the empirical tests of its assumptions and predictions. It is concluded that the SSDRs described by Bolles, along with some others, are highly probable in aversive situations but that the response repertoire is not limited to them. Further, there is strong evidence for reinforcement effects in the establishment and maintenance of at least some avoidance responses.