Investigation of the central auditory ability of binaural interaction in metalurgic workers with and without hearing loss

Abstract

We investigated the masking level difference (MLD) in noise exposed workers, with and without hearing loss, and compared the results to a control group. Group 1 was composed of 15 individuals with normal hearing thresholds and no exposition to occupational noise. 15 individuals with normal hearing thresholds and occupational noise exposition constituted group 2. Group 3 was composed of 15 individuals with occupational noise induced hearing loss. All subjects were submitted to the masking level difference for pure tones between 500 and 1000 Hz. The performance of groups 2 and 3 were worse than the performance of group 1 for 500 Hz. Group 2 presented normal results and group 3 presented abnormal results. The performance of groups 2 and 3 were worse than the performance of group 1 for 1000Hz. Both group 2 and 3 presented abnormal results. Noise exposition seems interfere with the central hearing abilities tested in MLD.