“…Another factor which might reduce the sensitivity of a postexperimental interview is the practice of questioning 5s following extinction trials (Buss et al, 1958;Cohen et al, 1954;Dailey, 1953;Essman, 1959;Grossberg, 1956;Hartman, 1955;Klein, 1954). An 5 who may have been aware of a correct contingency during the conditioning trials might not have reported it during the typical brief interview either because he forgot it or because he got the idea, during the extinction trials, that he had been wrong.…”