Auditory brainstem responses (ABR) in normal hearing adult subjects with Down's syndrome.

Background: Auditory brainstem responses (ABRs) have been previously investigated in subjects with Down's syndrome (DS), but the published data are generally from children with hearing loss. The aim of this study was to evaluate the hearing pathway in normal hearing adult DS patients. Methods: We used ABRs to analyze absolute and interpeak latencies in 19 adult DS patients aged 18–45 years whose pure tone audiometry (PTA) test results indicated thresholds within normal limits, and 19 normal controls. Results: The DS sample showed statistically significant gender-related differences in interpeak interval III–V (p=0.015). The latencies of waves III and V, and interpeak intervals III–V and I–V, were significantly shortened in the DS patients than in the controls. Conclusions: Our findings may be due to the smaller brain sizes and simpler afferent auditory pathways of DS subjects.