Loudness functions and temporal resolution for hearing impaired listeners

Abstract

Loudness perception was measured using a magnitude production procedure. Temporal resolution was measured in the same listeners using a tuning curve masking paradigm and a two-interval forced-choice adaptive procedure. Loudness functions were measured for pure tone signals at 500, 1000, and 3000 Hz with durations of 20 and 500 ms. The signal and masker for the temporal masking experiment were 20-ms sinusoids in phase at 500, 1000, or 3000 Hz. Quiet and 80-dB SPL broadband noise backgrounds were employed for both experiments. There were four primary findings. First, the loudness scaling data agrees with previous literature employing other techniques. Second, the hearing impaired listeners have broader than normal temporal masking functions in the quiet. Third, in the noise conditions, the two groups have broader functions than in quiet. Fourth, the temporal masking functions for the normal and hearing impaired listeners in a noise background are virtually parallel. Interrelations between the loudness and temporal masking data will be discussed. [Work supported by Hoover Foundation.]