Central auditory processing skills in stuttering school-age children with and without dyslexia: a preliminary study

Central auditory processing disorder (CAPD) has been linked separately to developmental stuttering (DS) and developmental dyslexia (DD), with limited information available when both disorders are present. Our study aimed to evaluate central auditory processing (CAP) in children with both disorders.

The study included 39 children distributed into three groups: two stuttering groups, with dyslexia (n= 13: 9 males, 4 females), and without dyslexia (n= 13: 10 males, 3 females), and a typically developing group (n= 13: 8 males, 5 females). The three groups were aged 6-12 years. Both stuttering groups had a formal quantitative assessment for stuttering severity. The three groups were assessed using the behavioral Arabic version of CAP.

There was no significant difference between the groups regarding age and sex distribution. There was no significant difference between both stuttering groups regarding the quantitative measures of stuttering severity. Both stuttering groups had significantly lower scores than the typically developing group for the dichotic digits test (DDT), binaural fusion (BF), pitch pattern sequence (PPS) test, and the right ear speech intelligibility in noise (SPIN) tests. The PPS scores were significantly lower in the group with both disorders. There was a significant correlation between some behavioral CAP assessments (e.g., DDT, BF, and PPS) and quantitative stuttering measures in the group of DS without DD.

Co-occurrence of DS and DD may be associated with exacerbated CAPD, particularly in temporal ordering, pattern recognition, and dichotic listening. Concomitant fluency and literacy disorders may have the potential to negatively impact CAP abilities. Therefore, CAP assessments should be incorporated in comprehensive evaluations for children with stuttering and dyslexia to maximize the effectiveness of targeted intervention outcomes.