Accession Number : AD0751179

Title :   The Relationship Between Permanent Threshold Shift and the Loss of Hair Cells in Monkeys Exposed to Impulse Noise.

Descriptive Note : Progress rept.,

Corporate Author : ARMY MEDICAL RESEARCH LAB FORT KNOX KY

Personal Author(s) : Pinheiro,Marilyn ; Jordan,Valdemar ; Luz,George A.

Report Date : 30 JUN 1972

Pagination or Media Count : 20

Abstract : A compariosn of permanent threshold shift sustained by monkeys exposed to impulse noise with hair cell and nerve fiber loss in their inner ears demonstrated that impulse hoise damages the cochlea by destroying hair cells in a restricted area. Although this destruction was not disclosed by pure tone audiometry until there was a severe loss of outer hair cells extending over several millimeters of the basilar membrane, the overall correlation between the two measures of damage (audiometric and histological) was statistically significant. Individual deviations were hypothesized to be due to the redundancy among the population of sensory cells in the inner ear, spread of excitation as a function of intensity, release from inhibition or masking, and a possible change in the elasticity of the denuded basilar membrane which might have affected the traveling wave pattern. (Author)

Descriptors :   (*NOISE, *AUDITORY NERVE), EAR, SENSE ORGANS, NERVE FIBERS, HEARING, STRESS(PHYSIOLOGY), THRESHOLDS(PHYSIOLOGY), MONKEYS, EXPERIMENTAL DATA, AUDIOMETRY, HISTOLOGY

Subject Categories : Stress Physiology

Distribution Statement : APPROVED FOR PUBLIC RELEASE