CONCERTS ON AUDITORY FUNCTION

The purpose of this paper is to determine the exact dangers of leisure music to society, as peoples’ hearing can be negatively impacted by excessive exposure to music, in terms of both duration and sound (dB) level. Two types of studies are analyzed. One study analyzes the effects of concert and disco style music on musicians and party guests, primarily through experiments which test pure-tone audiometry, distortion product otoacoustic emissions (DPOAE), and general sound levels of people and places before, during, and after exposure. Another study analyzes the effects of personal listening devices (PLDs) on the population, mainly through studies, questionnaires, hearing tests, and experiments. The results of many studies show that, due to the popularity of personal listening devices, people are listening to more music, more often, in more places, and at higher dB levels than ever before. The results determine that whereas both PLDs and concerts are harmful to society, PLDs pose a greater threat to users’ auditory functions. INTRODUCTION In America today, over 27 million people suffer from moderate levels of hearing loss, and the numbers are steadily increasing (Daniel 2007; Matusitz and McCormick 2010). About half of these people lose a portion of their hearing due to exposure to loud noise for just a short period of time (Daniel 2007). Many are school-age children and young adults who voluntarily expose themselves to increasingly loud music over time (Matusitz and McCormick 2010). Adults have begun to lose their hearing at earlier ages than ever before, and more young children and teenagers have begun to suffer from hearing loss than in years past. The National Institute for Occupational Safety and Health (NIOSH) has found that 30 million Americans are exposed daily to unsafe levels of noise, and that one out of every eight children shows symptoms of hearing loss (Daniel 2007). How loud is loud noise? The National Institute for Occupational Safety and Health states that exposure to sound levels above 85 dB over the course of an eight-hour work day is considered hazardous to one’s hearing because it can cause damage to hair cells or actually cause temporary hearing loss. Although it is well known that prolonged exposure to loud noise will likely cause damage to one’s hearing, studies have shown that even brief exposure to noise levels above 85 dB can potentially damage the hearing (Daniel 2007; Matusitz and McCormick 2010). In this paper, sound volume and length of exposure are highlighted because they are the two exposure factors over which individuals have the most control. The most common form of hearing loss is noise-induced hearing loss (NIHL). What exactly is noise-induced hearing loss, and how does it occur? In the cochlea, a section of the inner ear, there is a region called the Organ of Corti which contains inner and outer hair cells embedded in a sensory epithelial layer of tissue. The Organ of Corti is situated on top of the basilar membrane which is stiff and wide in some areas and the opposite in others. Sound waves vibrate the basilar membrane; low frequencies vibrate the apical section, and high frequencies vibrate the basal section. The inner hair cells of the cochlea normally transmit the vibrations from the ear to the brain via transduction, which causes an impulse to go from the eighth cranial nerve in the inner ear to the cerebral cortex. The outer hair cells (OHCs) “boost the stimulus by 23