SINGLE-INCENTIVE SELECTIVE ASSOCIATIONS PRODUCED SOLELY AS A FUNCTIONOF COMPOUND-STIMULUS CONDITIONING CONTEXT

Barpressing was maintained in a tone-plus-light (TL) condition in 2 gr oups of rats by shock-related contingencies and in 2 other groups by f ood-related contingencies. Responding ceased in TL absence (TLBAR). Co ntingency arrangements made TL hedonically positive, relative to TLBAR , for 1 shock group and for 1 food group and hedonically negative for 1 shock group and for 1 food group. In a stimulus-element test, the vi sual modality was dominant when TL was hedonically positive, whereas a uditory control increased when TL was negative, irrespective of the re inforcers involved. Within-incentive contingency manipulations produce d selective associations hitherto ascribed to stimulus-reinforcer inte ractions, suggesting that biological constraints on learning may opera te at the level of conditioned psychological states.