Audiology (Mar 1999)
Anatomical Changes in Auditory System Induced by Sound
Abstract
Sounds situated in a certain domain of intensity can evoke auditory system physiologically. Permanent and continuous stimulation which is produced by such sounds would not be harmful to hearing organ. This safe intensity is estimated 61 dB SPL. However one should pay attention that in case the intensity of mechanical sound wave increases (more than 75 dB SPL), the exposure time should be decreased unless the serious harm to auditory system is expected. Auditory system can be affected due to sound harms in two major types: Permanent threshold shift and temporary threshold shift which can be described as the changes in hearing status of human caused by the exposure to sententorian sounds. Numerous physiological factors can exacerbate the devastating effects of sounds that we are aimed at an overall description on this issue in the present review article.
