Electrophysiological correlates of stuttering severity: An ERP study.

Although a variety of theories have been proposed to explain the etiology of stuttering, the exact neurological origin of it is still uncertain. The aim of this study is to investigate the correlation between stuttering severity and ERP measures. The population of this study consisted of 12 adults with moderate, 12 adults with severe stuttering, and 12 fluent speakers as the control group. ERPs were recorded during an auditory task in which subjects should determine an oddball stimulus. The result of mismatch negativity (MMN) amplitude analysis revealed significant differences between severe stuttering and fluent speakers groups and between two stuttering groups. Moreover, the result showed significant differences between the three study groups for P300 amplitude. The findings of the present study suggest that the differences in ERP components are existed not only between people who stutter and fluent speakers but also between people with different levels of stuttering severity.