Conditioned inhibition in the spatial domain.

Using a variation on the standard procedure of conditioned inhibition (Trials A+ and AX-), rats (Rattus norvegicus) in a circular pool were trained to find a hidden platform that was located in a specific spatial position in relation to 2 individual landmarks (Trials A --> platform and B --> platform; Experiments 1a and 1b) and to 2 configurations of landmarks (Trials ABC --> platform and FGH --> platform; Experiment 2a). The rats also underwent inhibitory trials (Experiment 1: Trials AZ --> no platform; Experiment 2a: Trials CDE --> no platform) interspersed with these excitatory trials. In both experiments, subsequent test trials without the platform showed both a summation effect and retardation of excitatory conditioning, and in Experiment 2a rats learned to avoid the CDE quadrant over the course of the experiment. Two further experiments established that these results could not be attributed to any difference in salience between the conditioned inhibitors and the control stimuli. All these results contribute to the growing body of evidence consistent with the idea that there is a general mechanism of learning that is associative in nature. PsycINFO Database Record (c) 2009 APA, all rights reserved.