Second-order fear conditioning as revealed through augmentation of a startle response: Part II

Abstract

An auditory startle stimulus was presented 1, 17, and 27 sec following termination of a second-order, classically conditioned, fear-evoking CS. Forward second-order conditioned Ss consistently exceeded the startle magnitudes of backward second-order conditioned controls at all intervals. An analysis of movement during the CS2-startle intervals indicated that a postural interpretation could not account for startle augmentation in experimental Ss. A drive-like construct was posited to handle these data.