Abstract

Fine Motor Skills and Hand Preference Consistency in Children

by

Atefeh Karimi

School readiness represents a critical developmental milestone that predicts later academic success, yet the role of motor development in school readiness has been relatively understudied, particularly in populations at behavioral risk. Preschoolers with externalizing behavior problems (EBP) often experience difficulties transitioning to formal schooling, but substantial variability exists in their school readiness outcomes. This dissertation examined fine motor skills, executive function (EF), and hand preference consistency as interconnected contributors to school readiness in preschoolers with EBP. In study 1, I estimated the prevalence of fine motor skill deficits and examined their association with school readiness in a treatment-seeking sample of preschoolers with EBP. I found that a substantial proportion of children exhibited borderline to severe deficits in both manipulation and writing skills, and that fine motor performance was significantly associated with school readiness outcomes. In study 2, I examined the unique and combined contributions of fine motor skills and executive function to school readiness before and after participation in a school readiness intervention. I found that fine motor skills uniquely predicted school readiness at baseline, while both fine motor skills and executive function contributed to outcomes following intervention. In study 3, I investigated hand preference consistency as a potential neurodevelopmental mechanism underlying individual differences in fine motor skill proficiency and responsiveness to intervention using the Quantitative Hand Preference (QHP) task. I found that variability in hand preference consistency was associated with differences in motor performance and gains following intervention. This dissertation contributes to the literature by demonstrating that fine motor deficits are highly prevalent and functionally significant in preschoolers with EBP, by clarifying the role of fine motor skills and executive function in school readiness, and by introducing hand preference consistency as a novel neurodevelopmental factor underlying variability in motor development. These findings highlight fine motor skills as a critical and modifiable target for early screening and intervention and provide a multi-level framework for understanding school readiness in this population.