Browsing by Subject "Hearing levels"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item Psychoacoustic analysis of the normal audiometric region in noise-induced hearing loss subjects(Texas Tech University, 1983-05) Selent, Leslie AnnAlthough only a few studies have shown evidence of damage to the lower audiometrie region in subjects who have permanent hearing loss as a result of noise, these efforts have not involved discriminating psyehoaeoustie tasks. Thus, the present research was undertaken to assess low-to-mid frequency auditory function in NIHL subjects. Specifically, four indices of audition more sensitive to auditory perceptive function were utilized to address the question: Does auditory dysfunction occur in the normal audiometrie region in subjects displaying noise-induced hearing loss?Item The effects on the human auditory system of intense music played in nightclubs(Texas Tech University, 1996-05) Fain, PeteApproximately 28 million Americans suffer from significant hearing loss, of which up to ten million of these cases can be attributed to occupational noise (Lankford, 1990). Although it is difficult to calculate how many Americans have acquired noise-induced hearing loss (NIHL) from recreational noise exposures, it is estimated that this population is even greater than those exposed to occupational noises at dangerous levels. One particular group of people to consider when dealing with intense recreational noise is those who frequent nightclubs. Nightclub attendees are generally exposed to continuous music for several hours at a sound pressure level of 95 to 100 dBA. Ten nightclub patrons with normal auditory systems were assessed to determine the deleterious effects produced by intense music played in nightclubs, and the recovery rate of the hearing mechanism. Each subject served as his/her own control by establishing baseline one hour prior to entering the nightclub. The experimental protocol included pure-tone audiometry, acoustic reflex threshold and latency testing, and distortion-product otoacoustic emission evaluation. Each subject wore a dosimeter inside the club to average the intensity of the music the night of their participation. Each subject remained inside the nightclub for four hours, then received three more evaluations at 3 0 minutes, 1.25 hours and 2.0 hours post-noise exposure. The test parameters that had not recovered within this test time were re-evaluated each subsequent day until baseline status was regained. The most affected test parameters were pure-tone thresholds, which showed a high-frequency shift (up to 3 0 dB at 4000 Hz) and acoustic reflex sensation levels. These alterations remained significant through the third post-test for frequencies through 4000 Hz. The 6000 Hz and 8000 Hz pure-tone thresholds recovered after the fourth post-test. Acoustic reflex latencies and distortion-product otoacoustic emissions remained relatively unchanged post-noise exposure.