Hand Preference in Developmental Stuttering: A Test of the Geschwind-Galaburda Hypothesis of Hemispheric Specialization (P07.178)

Abstract

Objective: Our hypothesis was that people who stutter (PWS) are more likely to have atypical hand preference; to test this we measured the association of stuttering with gender and hand and foot preference. Background Geschwind and Galaburda postulated that functional inter-hemispheric differences reflect the extent of anatomical differences. From this idea they postulated that atypical cerebral lateralization underlies stuttering and thus stuttering would be associated with both left-handedness and gender. Design/Methods: Individuals on the Stuttering Foundation of America9s mailing list were asked to complete a mail survey and to distribute it to acquaintances. The survey included questions about gender, demographics and stuttering as well as 42-item hand-preference and 12-item foot-preference inventories (HPI and FPI, respectively). Results were analyzed using logistic regression. Results: Four-hundred-eighty-six subjects currently stuttered out of 863 responders. Handedness and gender were significant predictors of stuttering. Males were more likely to stutter than females [OR=7.7 95%CI(5,10) p Conclusions: Our results confirm our hypothesis that atypical laterality, as reflected on scores from a handedness survey, is a predictor of stuttering. This relationship is complex due to its interaction with sex-linked factors. Handedness and sex-linked factors may influence cortical development in PWS. From our results we postulate that how females respond to higher estrogen or lower testosterone exposure in utero can lead to both atypical language organization and hand preference. The process leading to stuttering in males may be different affecting only language organization. Supported by: Stuttering Foundation of America. Disclosure: Dr. Lovera has received personal compensation for activities with EMD Serono, Teva Neuroscience, and Biogen Idec as a consultant. Dr. Corey has nothing to disclose. Dr. Foundas has nothing to disclose.