Temporal processing performance in cochlear implant users.

Objectives: Auditory temporal resolution one of the main capabilities of the central auditory system and it is the main feature of speech processing abilities. Gap in noise test (GIN) is the one of the tests for assessing temporal resolution. In this study we aimed to assess and compare temporal resolution ability of subjects who wear cochlear implants (CI) and normal-hearing listeners with GIN test. Material and methods: It was a cross-sectional and descriptive study, with a non-probabilistic sample for convenience. In the study subjects was divided into two groups. First one is consisted of 14 adult users of cochlear implants who have approximately normal hearing in free field and second one is consisted of 14 adults with normal hearing, matched for age and gender with the study group. The Gaps in Noise test were conducted in free-field and was applied at 50 dB SL. Data was analyzed by independent paired t- test using SPSS software version 23. Results: The average of free field threshold was 29.3±6.8 dB HL at CI users. The average of pure tone threshold was 18± 2.7 dB HL at normal hearing subjects. The mean of GIN threshold was significantly higher and total percentage score was significantly lower in the CI user group compared to the normal hearing group. There was significant difference in approximate threshold and percent of corrected response between CI users and normal-hearing subjects (p<0.05). Conclusions: The results demonstrated that subjects with CI can never have as good temporal resolution as normals, although they have normal hearing. They have significant alterations in temporal processing abilities in comparison to subjects of the same age with normal hearing. [ABSTRACT FROM AUTHOR]