Effect of varied taste experience on negative contrast in consummatory behavior.

Rats shifted from 32% to 4% sucrose consume less 4% sucrose than animals that experience only the 4% solution. Previous experiments have suggested that a stress/emotional factor may be causally related to this negative contrast effect on the second postshift day, but not on the first postshift day. The present experiment was concerned with the possibility that contrast on the first postshift day is related to a neophobic response to the postshift solution. Results showed that giving animals experience with variously flavored (seven different flavors) 32% sucrose during the preshift period reduced degree of contrast when the animals were shifted to 4% sucrose. These data are considered in terms of solution novelty, specific loss of "sweetness", and caloric loss as contributors to negative contrast.