Auditory processing ability in Thai native speakers with the Gaps-In-Noise (GIN) test

Auditory processing disorder (APD) arises from dysfunctions within the central auditory nervous system (CANS). One key tool for assessing temporal auditory processing capabilities is the Gaps-In-Noise (GIN) test. While the GIN test serves as a critical tool, its accuracy may be influenced by linguistic factors. This research aims to establish preliminary normative data for the GIN test among young adult native Thai speakers and to compare potential performance differences across ears and various linguistic backgrounds.

This study included 52 native Thai speakers aged 18 to 25, all of whom had normal hearing confirmed through pure-tone audiometry, to examine auditory processing using the GIN test. The testing was conducted in an anechoic chamber to ensure standardized conditions. The results were analyzed based on the approximate gap-detection threshold (A.th.) value and the overall percent correct (OPC) value metrics.

The study revealed that, among young adult native Thai speakers, the A.th. values were 5.12-0.81 milliseconds (ms.) in the right ear, 5.08-0.81 ms. in the left ear, and 5.04-0.68 ms. for both ears. The corresponding averages of OPC values were 69.94-7.66% for the right ear, 71.37-7.21% for the left ear, and 71.35-6.72% for both ears, respectively. While no significant differences were observed in the threshold between ears, a notable discrepancy in response accuracy was noted, with the right ear showing lower accuracy than the left ear. Significant differences were also found when compared to English, Korean, and Portuguese language users, but not when compared to Polish language users.

The study revealed comparable temporal processing abilities among young adult native Thai speakers, as indicated by similar A.th. values across both ears. However, differences in the OPC value responses suggest potential asymmetries in auditory processing mechanisms. Additionally, linguistic factors appeared to influence the outcomes, as evidenced by variations in the A.th. values between Thai speakers and individuals from other linguistic backgrounds. These findings underscore the importance of incorporating language-specific norms when assessing the APD.