Conditioned taste and taste-potentiated odor aversions in the Syracuse high- and low-avoidance (SHA/Bru and SLA/Bru) strains of rats (Rattus norvegicus).

Syracuse high- and low-avoidance Long-Evans rats (Rattus norvegicus; SHA/Bru and SLA/Bru) were selectively bred for good and poor active-avoidance learning. However, SLA/Bru animals are superior to SHA/Bru rats in conditioned suppression and passive avoidance learning. In this experiment, saccharin taste and almond odor were the components of a compound conditioned stimulus (flavor) in an illness-induced aversive conditioning paradigm. SLA/Bru rats (n = 17) showed stronger conditioned flavor, taste, and odor aversion than did SHA/Bru animals (n = 18). Unselected Long-Evans rats (n = 18) were intermediate between the selected strains. SLA/Bru and Long-Evans rats showed taste-potentiated odor aversions in this experiment, whereas SHA/Bru animals did not. The results provide evidence that genetic factors, as exemplified by the different strains, are importantly involved in the mechanisms underlying interoceptive and exteroceptive aversive conditioning.