Retroactive revaluation of an odor-taste association

Rats showed an increase or decrease in preference for an aqueous odor conditioned stimulus (CS) presented in compound with a palatable (sucrose) or unpalatable (quinine) taste unconditioned stimulus (US), respectively. Four experiments then studied the consequences for odor preference of presenting water in the context where the odor-taste compound had previously occurred (i.e., no-CS-no-US experience). Exposure to that context increased the preference for the odor associate of sucrose and decreased preference for the odor associate of quinine. The increased preference for the odor associate of sucrose was contingent on reexposure to the context where the odor-sucrose compound had occurred (i.e., retroactive revaluation) and was reduced by preexposure to the context where the odor-sucrose compound was to occur (i.e., latent inhibition of the context). The retroactive revaluation of within-event learning caused by exposures to the associated context is discussed in terms of (1) the modified version of the SOP model (Wagner, 1981) proposed by Dickinson and Burke (1996) and (2) the comparator model (Miller & Matzel, 1988).