The role of tuning curve variables and threshold measures in the estimation of sensory cell loss.
Ahroon-WA; Davis-RI; Hamernik-RP
Audiology 1993 Jul; 32(4):244-259
The study examined the relative contribution of permanent threshold shift (PTS) and three tuning curve (TC) variables across the entire cochlea to the prediction of sensory cell loss within any specific octave band length of the cochlea using linear and multivariate statistical analyses. Auditory evoked potential TCs were collected at six frequencies before and 30 days after various noise exposures in 363 chinchillas using a simultaneous masking paradigm. In an effort to determine the extent to which sensory cell damage could be estimated from a knowledge of audiometric and TC variables, traditional bivariate and multiple linear regression/correlation analyses were performed. Strong correlations were noted between the percent outer hair cell loss and PTS and between the percent of outer hair cell loss and the TC variables and high and low frequency slopes. The correlations were strongest between PTS and percent of outer hair cell loss. The proportion of variability in the percent of outer hair cell loss attributable to variability in the predictor variables could be increased significantly by adding the variable of the TC whose probe frequency was centered in the octave band length of the cochlea corresponding to the frequency at which the PTS occurred. A further reduction in the proportion of variability values was obtained by including audiometric and tuning curve variables from frequencies adjacent to the octave band being evaluated.
NIOSH-Publication; NIOSH-Grant; Noise-induced-hearing-loss; Noise-exposure; Laboratory-animals; Ear-disorders; Hearing-threshold; Sensory-thresholds
Communicative Disorders & Scis Research Foundation of Suny P O Box 9 Albany, N Y 12201
Plattsburgh State University, New York