Accession Number : ADA294548

Title :   The Effects of Reverberant Blast Trauma (Impulse Noise) on Hearing: Parametric Studies.

Descriptive Note : Final rept. 9 Sep 91-8 Sep 94,

Corporate Author : STATE UNIV OF NEW YORK AT ALBANY RESEARCH FOUNDATION

Personal Author(s) : Hamernik, Roger P. ; Ahroon, William A. ; Lei, Sheau-Fang

PDF Url : ADA294548

Report Date : OCT 1994

Pagination or Media Count : 97

Abstract : The effects of exposure to high levels of reverberant blast waves (impulse noise) on the auditory system using an animal (chinchilla) model are reported. Blast waves were generated by two different shock tubes which produced wave signatures having different spectral distributions of energy. Intensities for each blast wave source were 150, 155, and 160 dB peak SPL with exposure to 1, 10, or 100 impulses. Repetition rates were fixed at one impulse/sec. There were 15 subjects per group. Brainstem evoked potentials were used to estimate temporary and permanent threshold shifts and conventional surface preparations of the cochlea were used to quantitatively assess sensory cell loss. In addition, pre and postexposure cubic distortion product otoacoustic emissions (3DPE) were collected on a subset of these animals for correlation with audiometric and histological indices of trauma. Trauma systematically increased with sound exposure level (SEL) and was dependent on the energy spectrum of the impulse. An application of the A and P weighting functions to the spectra improved the correlations between indices of trauma and SEL. The 3DPE data were consistent with PTS and, overall, both measures were correlated with sensory cell loss. (AN)

Descriptors :   *BLAST WAVES, *IMPULSE NOISE, *HEARING, *TRAUMA, PEAK VALUES, EXPERIMENTAL DATA, PARAMETRIC ANALYSIS, REPETITION RATE, COMPARISON, SHOCK WAVES, SHIFTING, NERVE CELLS, SPECTRAL ENERGY DISTRIBUTION, SOUND WAVES, EXPOSURE(PHYSIOLOGY), RESPONSE(BIOLOGY), RODENTS, REVERBERATION, ACOUSTIC EMISSIONS, SOUND PRESSURE, THRESHOLDS(PHYSIOLOGY), SENSES(PHYSIOLOGY), HISTOLOGY, SHOCK TUBES, PSYCHOACOUSTICS, AUDITORY PERCEPTION, AUDIOMETRY, COCHLEA.

Subject Categories : Anatomy and Physiology
      Acoustics

Distribution Statement : APPROVED FOR PUBLIC RELEASE