Hypothermia modifies the effective CS–US interval in conditioned taste aversion in rats

Abstract

Conditioned taste aversion can be acquired when rats experience an unconditioned stimulus (US) while anesthetized. In contrast to anesthetics, a hypothermia-induced comatose state immediately after presentation of a taste conditioned stimulus (CS) prevented a taste-illness association at relatively short CS–US intervals and potentiated the aversion at longer intervals. Results at shorter CS–US intervals were explained on the basis of hypothermia’s temporally graded amnesitc properties. Evidence for conditioning at the longer intervals was discussed in relation to slowing down metabolism allowing for associations to be formed at CS–US intervals that normally do not result in evidence of conditioning. Manipulating body temperature during the CS–US interval was demonstrated to alter rats’ ability to bridge temporal gaps in associative learning.