ABSTRACT
Tolman distinguished two kinds of learning: Field expectancies or cognitions are acquired in Pavlov’s CS-US and Thorndike’s R-US paradigms, wherein animals “map” the spatiotemporal context of the stimulus field and subsequently modify their behavior. Cathexis is a Darwinian process exemplified by flavor aversions, wherein the affective value of a goal object (US) is modified according to homeostatic feedback (FB). The latter process is characterized by one-trial learning over long temporal spans often occuring in the absence on any observable reaction to the prolonged paired stimulation. Flavor paired with a nauseous agent results in an aversion even at doses too low to induce nausea. In feeding, taste plays the pivotal US role ending the cognitive CS-US coping sequence and initiating the affective US-FB adjustment. In addition, taste potentiates weak distal CSs for feeding. Implications of the CS-US-FB schema for theories of CS-US associative similarity, CS-CS facilitation of long-delay learning and CS-CS competitive blocking are discussed. Examples of the duality of cognitive-affective processing are drawn from evolution and comparative neuroanatomy as well as from experiments and observations of animal and human behavior. Tolman’s legacy is fondly recalled.
