Auditory neural encoding of speech in adults with persistent developmental stuttering

Abstract Background: Stuttering is a speech disorder with frequent and protracted prolongations, repetitions, and silent blocks that hamper proper speech production. It develops during the preschool years with a prevalence of 5%, decreasing to 1% in adulthood to be referred to as persistent developmental stuttering. Auditory processing deficit is proposed to be one of the contributing factors to developmental stuttering. Objective: This study aimed to determine the pattern of auditory processing affection if any in stuttering disorder. This might be helpful for improving management approaches in the future. Patients and methods: Eleven adults with persistent developmental stuttering and 11 comparative age-matched normally fluent participants were examined with auditory brainstem response (ABR) and mismatch negativity to evaluate the brainstem and cortical processing of speech syllables, respectively. Results: All participants exhibited normal brainstem processing of nonspeech (click) stimuli, whereas 72.7% of stutterers revealed prolongation of peak latency of all waves of speech-evoked ABR. An additional peak latency delay of mismatch negativity response was found in 81.8% of stutterers. Conclusion: Auditory processing abnormality is proposed to be the underlying deficit in a subset of stutterers. © 2014, The Egyptian Oto - Rhino - Laryngological Society.