Relationship of negative contrast to animal models of fear and anxiety

Abstract

The relatedness of behavior elicited by reward reduction (successive negative contrast procedure) and behaviors produced by three animal models of anxiety (open-field emergence, elevated plus-maze, and context-shock fear conditioning) was examined by correlational and factor analytic procedures. Factor analysis (oblique rotation) indicated substantial independence among the tests: Trials 1 and 2 of the plus-maze loaded on two different factors unaccompanied by any other test; open-field emergence and context-shock fear loaded on the same factor; and negative contrast loaded on a fourth factor. However, negative contrast proved to be a dynamic process, with factor loadings changing across a 4-day postshift period - moving from an independent loading on the 1st postshift day to being clustered with context- shock fear and open-field emergence on the 2nd and 3rd postshift days to being clustered with just context-shock fear on the last postshift day. These latter data support a multistage theory of successive negative contrast.