Neurophysiologic Measures of Auditory Brainstem Responses to Hindi Speech Stimulus in Typically Developing Children

Abstract

Context: Speech evoked auditory brain stem responses (spABR) are used to assess brain stem ability to encode speech. However, brain stem representations of speech sound are affected by acoustic differences of speech, language background and experiences. Hence, linguistically and culturally specific stimulus should be used. Therefore, there is need to investigate the brain stem encoding of Hindi speech sound. Objective: The purpose of the study was to investigate the spABR to Hindi stimulus in typically developing children. Methods and Material:Total 25 atypical children of the mean age of 6.3 years with SD 2.3 years in the age range of 8-12 years were recruited. A 40ms duration Hindi stop phoneme of CV combination |da| was synthesized to gain response of consonant (transient) and vowel (sustained) portion of speech stimulus from all subjects. Results: The spABR latencies and amplitudes of discrete peaks as well as the latency, amplitude, area & slope of V-A complex were measured. The stimulus to response timing and spectral magnitudes of periodic portion were also calculated. The mean, median, standard deviation, minimum, maximum and 95% confidence interval values were calculated. Conclusions: The obtained spABR values suggest faithful representation of acoustic characteristic of speech at brain stem level. These values are found to be similar with previous reports. Hence, spABR can serve as important tools in the diagnostic work up of auditory processing deficits in children to understand speech perception and production abilities.