EXTINCTION OF WITHIN-EVENT LEARNING IS CONTEXTUALLY CONTROLLED AND SUBJECT TO RENEWAL

Five experiments examined within-event learning in rats by inducing an appetite for one of the elements (salt) of a compound stimulus and as sessing preference for the other element (almond). Almond preference w as conditional upon (1) the almond flavour having been presented in co mpound with the salt, and (2) the assessment being conducted when the rats were out of sodium balance (Experiment 1). Presentations of the c ompound in one environment (A) and of the salt and almond elements in a second environment (B) resulted in greater almond preference when ra ts were tested in A than in B (Experiment 2). Almond preference was re duced when separate presentations of the compound and almond (Experime nt 3) or of the compound and salt (Experiment 4) occurred in the same environments but not when these presentations occurred in different en vironments. Rats exposed to the compound in A and then extinguished to the elements in either A or B showed a reduced almond preference when tested in the extinction environment, but not when tested in the othe r environment (Experiment 5). Thus, extinction of within-event learnin g is context-specific and subject to renewal. The results were interpr eted in terms of an associative model whereby separate presentations o f the elements result in a symmetrical inhibitory link which is contex tually gated (Bouton, 1993).