Abstract

Change in masked pure-tone detector thresholds as a function of intense noise exposure is of interest for both theoretical (neural coding) and practical (damage assessment) reasons. Thresholds for detection of a 3000-Hz tone embedded in a 2125- to 4250-Hz octave band of masking noise were determined before and after intense noise exposure. Masking noise levels were varied from 0 to 45 dB SPL. The intense noise was a 1200- to 2400-Hz octave band of white noise set at intensities of 90, 100, or 110 dB SPL. Each observation consisted of the following parts: (1) pre-intense noise exposure threshold determination, (2) 3-min exposure to intense noise, (3) 90-sec delay, and (4) post-intense noise exposure threshold determination. The results of a series of observations employing the above procedure indicate that pure-tone thresholds were elevated following the intense noise exposure by 4 to 9 dB when the tone was embedded in 0-dB masking noise (TTS2=4 to 9 dB), However, pure-tone detection thresholds were elevated following intense noise exposure by only 0.5 to 3 dB when the tone was embedded in 25- to 45-dB masking noise. Possible neural mechanisms that might account for these observations are considered. [Work supported in part by U. S. Air Force Contract F33 615 73C 4002.]

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call