Acoustic Reflexometry

Abstract

A more systematic and rapidly conducted procedure has been devised for auditory stimulation, in the manometric testing of acoustic reflex reactions. The stimuli are brief pulses of changing tones. They are swept from one end of the test frequency scale to the other during a single, uninterrupted recording, at starting amplitudes below or just above reflex threshold. Stimulus strength is raised progressively between repetitive recordings from the same ear. The results have facilitated the comparison of reflex reactions with relation to the stimuli. Wide differences have been found in the effectiveness of particular stimuli and in the appearance of the responses, in a small group of normal subjects. In a few individuals the recorded reactions to some of the stimulus combinations have varied in either a single ear or in both ears. The most extreme type of change has been between momentary protrusion and momentary retraction of the tympanic membrane. The method has yielded consistent results throughout single tests and in repeated tests on the same subject.