Classical Conditioning of the Stapedius Muscle

Abstract

A delayed conditioning paradigm was employed to condition the stapedius muscle. While many previous attempts have failed using loud sound as the unconditioned stimulus (UCS), this paper presents evidence of successful conditioning of this muscle when the unconditioned stimulus was a mild electrocutaneous stimulation of the external ear canal. Using a weak tone as the conditioned stimulus, conditioned responses were readily obtained in eight of ten subjects after only 30 or fewer tone-shock pairs. Temporal conditioning was also demonstrated. A parallel is shown to exist between attempts to condition the pupillary and stapedius reflexes.