Acquisition of superexcitatory properties by an irrelevant background stimulus.
Six appetitive conditioning experiments with rats demonstrated that an irrelevant X accompanying a negative patterning discrimination (XA+, XB+, XAB-) acquires extraordinarily high levels of conditioned excitation. Responding to X was similar to that evoked by 2 excitors in combination (Experiment 1) and was greater than responding to a separately reinforced Y (Experiments 2-5). Superexcitatory properties were not acquired by X in the nonpatterning discriminations of Experiments 2-4. Experiment 5 found that A and B, if anything, were weakly excitatory. Making them more strongly excitatory after conditioning did not interfere with retention of the original discrimination (Experiment 6). Results support a counterintuitive prediction of associative theories that, under carefully arranged conditions, irrelevant stimuli may acquire superexcitatory properties.
Psychology Department, University of Winnipeg, Winnipeg, Manitoba R3B 2E9, Canada. williams@uwinnipeg.ca
Douglas A
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Williams
Rick
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Mehta
Tracy M
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Poworoznyk
Jane S
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Orihel
David N
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George
John M
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Pearce
D000818:Animals; D001070:Appetitive Behavior; D004192:Discrimination, Psychological; D007858:Learning; D008297:Male; D008954:Models, Biological; D009622:Noise; D010470:Perceptual Masking; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012054:Reinforcement, Psychology; D012153:Retention, Psychology