A study of the central auditory function in stutters by masking level difference and synthetic sentence identification tests

There are evidences that indicate a relationship between auditory processing disor¬ders and stuttering,¬ and any disorder in the central auditory function can be at least one of the underly¬ing causes of stuttering. Even though, using the most state of the art radiographic technologies, i.e. MRI, no definitive answer has been given in relative to this question. In this research, using Mask-ing Level Difference (MLD) and Synthetic Sentence Identification (SSI) tests, the central auditory func¬tion of stutters and normal group was evaluated. In this study was analytic cross-sectional, fifteen male patients with stutter-ing and 15 male normal cases with the age range from 16 to 40 years (average age 26.78 year) were evalu¬ated. SSI-ICM, SSI-CCM and MLD tests were performed. The results were compared in both groups. Although stutterers mean MLD was less than that of normal group, the different was not signifi¬cant between stutters and normal group in SSI test in right ear at negative MCRs. There was a signifi¬cant difference in ICM state, but in CCM state, there was no significant difference between the aver¬age score of two groups in various MCRs. The findings of this research is compatible with those of similar researches about the SSI test and the pattern of results, probably indicates a partial dysfunction of brainstem in some of the stutters.