Recovery of the Auditory Threshold after Strong Acoustic Stimulation

Abstract

Recovery curves are given for the auditory thresholds of clicks, bands of noise, and pure tones, the fatiguing stimuli including bands of noise and pure tones. Recovery from such auditory fatigue is not a simple monotonic process. Rather, under certain conditions, the threshold 1st recovers to an approx. normal value about 1 min. after the cessation of the exposure, then rises to a higher value, reaching a max. about 2 min. after the exposure. This diphasic recovery curve, with its characteristic "bounce," is found when the exposure involves sound pressure levels between 100 and 120 db and durations of the order of several min. Qualitative observations concerning the pitch and timbre of the test stimuli and of tinnitus following stimulation are related to some of the data.