抄録
64 rats were run in a conditioned-suppression situation in order to test whether the Sutherland-Mackintosh's hypothesis or Rescorla-Wagner's hypothesis regarding the effect was adequate in explaining the Kamin's “blocking effect”. In Group PRD, in which conditioning of shock US to the compound stimulus (A+X) followed by the pairing of A with shock, conditioning to X was blocked. Group N and US, both of which had no experience with A prior to compound conditioning, revealed approximately equal amount of conditioning to both light and tone consisting A and X. In Group CS and RDM, in which A alone was presented and A and US were randomly presented, respectively, prior to compound conditioning, greater amount of conditioning was observed to X than to A. This finding supports Sutherland-Mackintosh's hypothesis.
