Psychology, Department of
Date of this Version
March 1997
Abstract
In a sample of 208 Holtzman-descended albino rats, we found evidence with 4 measures of conditioning (freezing, defecation, side crossing, and nose crossing) that a single 2-s, 1.0-mA immediate shock could condition fear to a context (Experiments 1, 2, and 4). When we reduced the shock intensity to 0.5 mA, we obtained a complete immediate-shock conditioning deficit according to all measures in Experiment 3 and to all but the defecation measure in Experiment 4. Results suggest two conclusions: (a) Differences in shock potency between laboratories may help explain discrepant findings about whether immediate shock supports contextual conditioning; (b) theories of contextual conditioning need a mechanism that permits that conditioning to result from immediate shock.
Comments
Published in Journal of Experimental Psychology: Animal Behavior Processes, Vol. 23 (1997), No. 3, pp. 312–324. Copyright © 1997 by the American Psychological Association. Inc. http://www.apa.org/journals/xan/. “This article may not exactly replicate the final version published in the APA journal. It is not the copy of record.” Used by permission.