The Increase in Prevalence of High Frequency Hearing Impairment Among College Students

Abstract

There are numerous intense sounds in the environment to which regularity. To assess the effect of such noise exposure upon the hearing of persons under 21, a 2-part study was conducted. In the Fall of 1968, 2 769 Freshman entering the University of Tennessee were given a modified screening test for hearing. The failure level was established to be 15 dB (ISO, 1964 standard). If a student failed at any frequency, his threshold for hearing was measured for that frequency and recorded on a printed form. It was found that 4.6% of the students failed to respond to a 2 000 Hz stimulus. Failure levels were found to be 6.8, 10.5 and 29.4% for 3 000, 4 000 and 6 000 Hz, respectively. The procedure was repeated in testing 1 410 students in the Fall of 1969. It was discovered, however, that the prevalence of high frequency hearing impairment rose dramatically in this group. Failure rates were found to be 6.3, 13, 14.3 and 54.9% for the 2 000, 3 000, 4 000 and 6 000 Hz signals, respectively. Of the students tested, 7.4% had a hearing threshold of 40 dB or greater for the 6 000 Hz signal. Additional data are presented which indicate that the occurrence of measurable high frequency hearing impairment in young persons is tangible evidence of the toll being exacted by high intensity recreational and environmental sounds. The results of these studies are related to previous incidence studies and to histologic evidence of sensory cell damage observed in laboratory experiments.

Key Words:

• Noise-induced hearing loss
• Hearing screening test
• High intensity recreational sounds