Abstract
Twenty-eight rats were randomly assigned to four groups representing a factorial combination of two levels of preshift and two levels of postshift sucrose concentration. Following 220 preshift trials, the subjects were required to learn a brightness discrimination, and they either shifted to a novel reward concentration or maintained on the preshift magnitude. The results of an analysis of response speed indicated significant magnitude effects as well as NCE but no indication of PCE. Analysis of the number of errors indicated NCE but not PCE. The results were discussed with reference to perceptual and sequential theories of contrast effects.
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This research was supported by a grant to the second author from the Florida Atlantic University Research Committee.
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Moore, J.N., Adamson, R. Contrast effects accompanying shifts in sucrose concentration during the acquisition of a brightness discrimination. Bull. Psychon. Soc. 7, 393–396 (1976). https://doi.org/10.3758/BF03337226
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DOI: https://doi.org/10.3758/BF03337226