Late Recovery from Stuttering: The Role of Hand Dominancy, Fine Motor and ‎Inhibition Control

There are controversial reports about factors that affect recovery from stuttering. In the ‎present study, the effect of hand dominancy, fine motor and inhibition control on late ‎recovery from stuttering was investigated among a group of Kurdish-Persian children who ‎stuttered in Iran.‎ Twenty-two Kurdish-Persian children aged 7-14 years who stuttered were followed for 6 ‎years. Based on the evaluation of three experienced speech therapists and parental judgments, ‎these children were classified into recovered or persistent groups. Data about fine motor ‎control of hand and inhibition control were obtained, using Purdue Pegboard and Victoria ‎Strop Color Word Tests, respectively. Risk factors including sex, age, and family history of ‎stuttering, handedness, inhibitory control and fine motor control of hand were compared ‎between the groups and modeled to predict recovery from stuttering using logistic regression.‎ From the 22 participants, 5 (22.7%) recovered from stuttering. The recovered and persistent ‎groups did not show significant differences in the interference effect. By dividing the scores ‎of the Purdue Pegboard tests to the right and left hand, we created a new Handedness Index ‎‎(HI). HI was significantly higher in the recovered group. The score of right hand was higher ‎than the left in the recovered group, but no difference was found between the two hands in ‎the persistent group. Among the investigated risk factors, only HI could predict the recovery ‎from or persistency of stuttering with 94% sensitivity and 84% specificity.‎ Handedness Index can predict the recovery from stuttering significantly among children who ‎stutter.‎.