The White Noise Middle Ear Muscle Reflex Threshold in Patients with Sensorineural Hearing Impairment

Abstract

In normal subjects white noise is more effective than pure tones to elicit the middle ear muscle reflexes. Niemeyer & Sesterhenn found that this difference is smaller in patients with sensorineural hearing losses and diminishes systematically so that it can be used to predict the amount of impairment. Jerger et al. proposed a more refined method of prediction, which attributed a certain value to the absolute white noise reflex threshold and also included a weighting of the various pure tone reflex thresholds. In 58 patients and 12 normals we established the thresholds for these stimuli by computer averaging. The pure tone thresholds were largely independent of the hearing loss if this was not excessive but with considerable interindividual variations and only the white noise threshold appeared to be related to the degree of impairment and predictions based on this criterion alone should be quite promising. White noise delivers most of its energy to the basal part of the cochlea and high frequency hearing losses appear to be particularly important for the reflex threshold towards such a stimulus.