Nonacoustic stimulation of the middle ear muscle reflex.

The purpose of these experiments was to determine the incidence of the middle ear reflex in response to several nonacoustic (tactile and air jet) stimuli among subjects with normal hearing who had an acoustic reflex and selected patients with severe hearing loss. The results demonstrate that the incidence of response to tactile stimulation increases as the facial area stimulated approaches the auricle. The response to an air jet stimulus directed toward the eye is high; however, the clinical utility of the air jet may be limited because it often results in a startle reaction and head movement, and the response appears to fatigue easily. In normal listeners the response to auricular air jet stimulation probably results from both acoustic and tactile stimulation. The presence of a reflex to tactile stimulation, together with normal tympanometry constitutes strong evidence of a normal middle ear; but the absence of a reflex to acoustic or tactile stimuli still leads to an ambiguous determination of potential stapedial muscle function.