Post-noise-exposure auditory sensitivity and temporal integration recovery functions

Normal-hearing young adults (N:12) were exposed to a band-limited noise (1.4-2 kc/s) at 100 db SPL for 15 min. Pre- and post-exposure threshold measurements were made at 2 and 4 kc/s at durations of 500 and of 20 msec, at time intervals of TTS2, TTS15 and every 30-min interval thereafter for 4 hrs. Greater TTS occurred at both frequencies with the 500-msec than with the 20-msec duration. Threshold recovery patterns over time were similar for both durations but thresholds for the 20-msec duration recovered sooner. There was a delayed recovery function at 4 kc/s for the relative differences (20 vs 500 msec). Implications of the findings were discussed.