Objective: This study was a basic investigation of the ability of concurrent speech segregation in hearing impaired children. Concurrent segregation is one of the fundamental components of auditory scene analysis and plays an important role in speech perception. In the present study, we compared auditory late responses or ALRs between hearing impaired and normal children.

Materials & Methods: Auditory late potentials in response to 12 double vowels were recorded in 10 children with moderate to severe sensory neural hearing loss and 10 normal children. Double vowels (pairs of synthetic vowels) were presented concurrently and binaurally. Fundamental frequency (F0) of these vowels and the size of the difference in F0 between vowels was 100 Hz and 0.5 semitones respectively.

Results: Comparing N1-P2 amplitude showed statistically significant difference in some stimuli between hearing impaired and normal children (P<0.05). This complex indexing the vowel change detection and reflecting central auditory speech representation without active client participation was decreased in hearing impaired children.

Conclusion: This study showed problems in concurrent speech segregation in hearing impaired children evidenced by ALRs. This information indicated deficiencies in bottom-up processing of speech characteristics based on F0 and its differences in these children.