Speech and click evoked auditory brainstem response in delayed language children with normal pure tone audiogram

ABSTRACT

Children with normal auditory thresholds may still suffer from auditory processing disorders, resulting in poor speech understanding. Abnormal electrophysiological responses to speech syllables at the brainstem level have been associated with a wide spectrum of diagnosed learning problems. The aim of this study was to identify the pattern of speech evoked brainstem response in normal peripheral hearing children with delayed language development and to develop an objective method to test those children. The speech and click evoked ABR results of twenty children, their age ranging from 4-6 years [of both genders], complaining from delayed language development with normal pure tone audiogram and normal IQ results were compared to the results obtained from twenty normal children matching in age and gender. There was no significant difference in the wave V latency and amplitude values of click-evoked ABR in normal and delayed language subjects. However, a statistically significant difference between the wave V latency and amplitude values of the speech-evoked ABR in normal versus delayed language subjects was detected. There was also a highly significant difference in the duration and slope of the V-to-A transition between the two groups. Results obtained from this study suggest that speech evoked ABR may be a useful objective tool in the early diagnosis of children with delayed language development. More wide scale studies on speech evoked ABR must be conducted to obtain age related norms, and to assess other abnormalities such as learning disabilities