Effect of tinnitus location on the psychoacoustic measures of hearing

Abstract

Objective: The present study was designed to assess psychoacoustic abilities in individuals with the complaint of tinnitus, the emphasis being on the location of tinnitus in the head.Study design: Psychoacoustic abilities were measured with temporal processing tests using four common measures. Gap-in-noise and modulation function tests were used to measure temporal resolution ability; duration pattern and duration discrimination tests were used to assess temporal ordering and temporal discrimination skills, respectively; and finally a backwards masking test was employed to determine temporal masking abilities. A clinical research design using standard group comparison was used with a cohort of 76 normal hearing participants divided into three groups: one with no complaint of tinnitus (n = 38), a second with tinnitus localized to either one of the ears (n = 22), and a third with tinnitus localized to both ears (n = 16).Results: A comparison between the normal and tinnitus groups revealed poor temporal processing skills in individuals with tinnitus. Within the tinnitus group, a comparison between those with unilateral and bilateral tinnitus indicated poor performance of the participants with bilateral tinnitus for most of the tests. The individuals with unilateral tinnitus were also assessed for tinnitus ear effect and no statistically significant difference was observed.Conclusion: Temporal processing skills were affected in individuals with tinnitus and the severity was more in those with bilateral tinnitus. As persons with temporal processing disorders are at high risk of developing speech perception problems, the early investigation and timely management of tinnitus is essential.