Characteristics of Temporary and Permanent Threshold Shifts in Vertebrates
Studies of noise-induced threshold shift to acoustic over exposure, conducted in the laboratory, employ a simple and rigorous paradigm. First, hearing is measured usually as a series of thresholds for pure tones distributed throughout the range of hearing. Then the subject is exposed to a loud sound, after which estimates of threshold are repeated. A difference between the pre- and postthreshold values represents the consequences of the sound exposure. From this approach, much is known about the effects of intense sound exposure on hearing. This chapter reviews the data on temporary and permanent threshold shifts. Examples of noise-induced threshold shift (NITS) are drawn from the extensive animal literature obtained from a mammal (chinchilla) and several avian (budgerigar and chicken chick) species. The conclusions from these examples is that when the parameters of exposure are well characterized and thresholds carefully determined, a set of reliable and valid observations on the magnitude and duration of NITS emerge. Most importantly, certain aspects of hearing loss appear to be consistent across species. Given that a set of repeatable patterns of NITS are known, it is suggested that meaningful predictions can be made on the susceptibility of hearing loss in wild animals exposed to noise in natural environments. This suggestion assumes that the parameters of the exposure such as the sound pressure level and duration are reasonably well-known. The validity of these estimates has limitations and these are also considered.
KeywordsAdaptation Asymptotic threshold shift Continuous exposure Decibel Fatigue Hearing loss Impulse/impact exposure Intermittent exposure Noise-induced threshold shift Permanent threshold shift recovery Sound field Sound pressure level Temporary threshold shift Threshold shift
- Dooling, R. J., West, E. W., & Leek, M. R. (2009). Conceptual and computational models of the effects of anthropogenic noise on birds. Paper presented at the 5th International Conference on Bioacoustics 2009, Holywell Park, UK, March 31 to April 2, 2009. Proceedings of the Institute of Acoustics, 31, 99–106.Google Scholar
- Fleisher, G. (1978). Evolutionary principles of the mammalian middle ear. Advances in Anatomy, Embryology and Cell Biology, 55, 1–70.Google Scholar
- Miller, J. D., Watson, C. S., & Covell, W. P. (1963). Deafening effects of noise on the cat. Acta Oto-Laryngology, Supplement, 176, 1–91.Google Scholar
- Mills, J. H. (1976). Threshold shifts produced by a 90-day exposure to noise. In D. Henderson, R. Hammernick, D. S. Dosanjh, & J. H. Mills (Eds.), Effects of Noise on Hearing (pp. 265–275). New York: Raven Press.Google Scholar
- Moody, D. B., Sebbins, W. C., Johnsson, L. G., & Hawkins, J. E., Jr. (1976). Noise-induced hearing loss in the monkey. In D. Henderson, R. P. Hammernick, D. S. Dosanjh, & J. H. Mills (Eds.), Effects of Noise on Hearing (pp. 309–325). New York: Raven Press.Google Scholar
- Salvi, R., Lobarinas, E., Chen, G. D., Stolzberg, D., & Ding, D. (2011). Animal models of hearing loss and tinnitus. In J. Hau & S. Y. Schapiro (Eds.), Animal Models. Handbook of Laboratory Animal Science, vol. II 3rd ed. (pp. 419–453). Boca Raton, FL: CRC Press.Google Scholar
- Saunders, J. C., & Rosowski, J. J. (1979). The assessment of hearing in animals. In W. F. Rintlemann (Ed.), The Assessment of Hearing (pp. 487–529). Baltimore, MD: University Park Press.Google Scholar
- Saunders, J. C., & Dear, S. P. (1983). Comparative morphology of stereocilia. In R. R. Fay and G. Gourevitch (Eds.), Essays on Hearing in Honor of E. G. Wever (pp. 175–197). Groton, CT: Amphora Press.Google Scholar
- Spassova, M. A., Avissar, M., Furman, A. C., Crumling, M. A., Saunders, J. C., & Parsons, T. D. (2004). Evidence that rapid vesicle replenishment of the synaptic ribbon mediates recovery from short-term adaptation at the hair cell afferent synapse. Journal of the Association for Research in Otolaryngology, 5, 376–390.CrossRefPubMedPubMedCentralGoogle Scholar
- Tontechnik-Recher-sengplielaudio. (2016). How Does the Sound or Noise Depend on Distance from the Source? Audio Tutorial, Tonmeister Institut. Available at http://www.sengpielaudio.com/calculator-SoundAndDistance.htm. Accessed December 22, 2016.