Tek Taraflı İşitme Kayıplı Bireylerde Zamansal ve Suprasegmental İşitsel İşlemlemenin Değerlendirilmesi

Abstract

Asymmetric access of auditory stimuli to the brain as a result of unilateral hearing loss leads to cortical reorganizations. In patients with unilateral total hearing loss, localization of auditory stimuli, weakness in the ability to distinguish speech in noise and spatial clues, cortical changes associated with the impaired ear are well documented. However the studies evaluating their temporal and suprasegmental performance in the unimpaired, clinically normal ear are limited in the literature. Thus it was aimed to determine the temporal order, masking, resolution and affective prosody skills after reorganization in Single Sided Deafness (SSD) and to compare single and both ear performances in normal hearing same-sex peers. For this purpose, 30 subjects with SSD and 30 individuals with bilateral normal hearing (34 females - 26 males, mean age: 38,70 ± 11,59 years) were included in the study with age and sex matchings. The Single Ears of Individuals with Normal Hearing (NSE) and Simultaneously Both Ears (NBE) were evaluated in terms of Frequency Pattern Test (FPT), Duration Pattern Test (DPT), Backward Masking Test (BWM), Random Gap Detection Test (RGDT) and Affective Prosody test. Percentages of correct response in all tests and reaction times of FPT, SPT, and affective prosody were recorded and the results were compared between the groups. DPT, BWM and RGDT were statistically significant (p <0,01) between individuals with SSD and NBE however no statistically significant differences were found between TTİK and NSE (p> 0,01). There was no significant difference among groups according to FPT (p> 0,01). Although mean scores are lower in SSD group (SSD: 77,26 ±9,17- NSE: 77,83±8,51- NBE: 82,85±7,80) there were no statistically significant differences among to the groups according to affective prosody (p> 0,01) and reaction times of affective prosody (p>0,01). A statistically significant differences were found in reaction times of FPT and DPT (p <0.01). In addition temporal masking and order ability showed negative correlation with ageing (p <0.01). Positive correlation between affective prosody test and ageing were found (p <0.01). Temporal masking, temporal order and temporal resolution skills of pre and postlingual SSD patients were found to be weaker in both ear performances of normal hearing individuals. These results support the studies that plastic reorganizations may also be present in adult postlingual onset hearing loss. Affective prosody skills, which are obtained weakly in hemispheric lesion damage, are not affected by asymmetric auditory deprivation caused by peripheral unilateral hearing loss. Although there is no statistically significant difference between the frequency pattern performans, a significant difference between the reaction times of frequency patterns shows that temporal processing tests should be evaluated not only the correct answers but also the reaction times. It was the first study that evaluated the reaction times of temporal processing and affective prosody skills in individuals with SSD.