Handbook of Mouse Auditory Research: From Behavior to Molecular Biology. JF Willott, ed., New York: CRC Press, 2001 Jan; :477-488
Noise has been a universal problem from the time man first put hammer to stone. Our lives have not gotten any quieter. On-the-job hearing loss due to noise is the most common form of occupational injury in the United States. Estimates by the National Institute for Occupational Safety and Health (NIOSH) in the early 1980s estimated that about four million workers were exposed to noise in excess of 85 dBA (NIOSH, 1998). NIOSH calculates that a lifetime exposure to noise in excess of 85 dBA will cause an excess risk of 15% of those workers suffering a disabling hearing loss. With exposure to 90 dBA over a working lifetime, the estimated risk almost doubles to 29%. Current thinking is that every ear is vulnerable to noise- given enough acoustic energy at the right frequency for enough time. NIOSH (1988) identified noise-induced hearing loss as one of its top ten priorities. In the 1990s, it was again identified as a major public health priority by ASHA (Cherow, 1991). Based on testimony from industry, private organizations, and governmental agencies, the National Occupational Research Agenda (NIOSH, 1996) identified noise-induced hearing loss as a priority area for research. Hearing loss is common in the general population and appears to be more so (Ries, 1985). With the introduction of high-power audio systems, boom boxes, and car stereos, noise-induced hearing loss is here to stay. Civilian and military firearms use is an important contributor to loss of hearing (Ylikoski, 1994; Prosser et al., 1988). It is well known among practicing audiologists that all humans are not equally susceptible to the damaging effects of noise. Noise researchers know that noise susceptibility in experimental animals is quite variable (e.g., Cody and Robertson, 1983). The inbred mouse, while still variable from one mouse to another, appears to be less variable within strains. Between strains, the mouse shows great differences in susceptibility to noise as well as differences in prebycusis. The goal of this chapter is to review mouse noise-induced hearing loss research and speculate about organizing principles. Most noise-induced hearing loss research has not been done in the mouse, but rather in the chinchilla, guinea pig, cat, and even rabbit. In the past 10 years, there has been a renaissance in noise studies in mice. It is believed that mechanisms of noise-induced hearing loss cross species, but exceptions will be noted. For additional background information, the reader is referred a review of the literature on physiological effects of noise-induced hearing loss by Borg, Canlon, and Engstrom (1995).