Psychoacoustic correlates of susceptibility to auditory fatigue

The present study was designed to explore psychoacoustic correlates of susceptibility to auditory fatigue. Fifty-six normal-hearing subjects were given two monaural auditory fatigue tests. The high-frequency test consisted of a 3-min exposure to a 110 dB SPL, 2 kHz pure tone, with temporary threshold shift (TTS) measured at 4 kHz. The low-frequency test consisted of a 3-min exposure to a 115 dB SPL, 500 Hz pure tone, with TTS measured at 1 kHz. Amount of TTS and TTS recovery time were compared with performance on a test battery consisting of: (1) masking level differences; (2) brief-tone audiometry; (3) speech discrimination in noise; and (4) the threshold of octave masking test. A small negative correlation was found between amount of TTS and results of the threshold of octave masking test and the results of brief-tone audiometry. Subjects with larger amounts of TTS tended to have lower thresholds of octave masking and flattened threshold-duration functions.