Positive Interanimal Transfer with a Control for Arousal

Abstract

Three experiments used rats and a non-shock passive avoidance task to differentiate between learning and non-specific arousal hypotheses of the interanimal transfer phenomenon. In the first experiment with 57 rats, a multi-trial training procedure was used and positive transfer was obtained from rats receiving “trained-brain” extract injections but not from rats receiving injections of extracts from aroused controls. The second experiment used a one-trial training procedure with 49 rats and reproduced the results of Exp. 1. The third experiment with 56 rats showed some evidence of extinction and spontaneous recovery while this was not found with rats receiving injections from aroused controls. A fourth experiment indicated that the brain-extract solutions of Exps. 1 to 3 contained relatively high concentrations of protein. No detectable concentrations of RNA were discerned. The behavioral results were consistent with the notion that the interanimal transfer resulted from a learning transfer rather than a nonspecific arousal transfer.