Lateralization in children with Attention Deficit Hyperactivity Disorder

Abstract

Attention Deficit/Hyperactivity (ADHD) involves a constellation of symptoms such as inattention, hyperactivity and impulsivity. Disturbances in lateral preference in ADHD are of interest as they may explain deficiencies in brain development. The aim of this study was to determine the prevalence of lateralization in children with ADHD. One hundred and sixty children (80 with ADHD symptoms and 80 matched controls without ADHD symptoms), both male and female from the North-West and Limpopo provinces, aged between 7 and 13 years, participated in the study. Participants were tested on simple tasks to establish hand, foot, eye and ear dominance. The results revealed that crossed laterality was more prevalent in the ADHD group compared to the control group (79% v. 41%). The two groups were also compared on measures of inattention, hyperactivity/ impulsiveness, impairment, Oppositional Defiant Disorder and Conduct Disorder to establish whether laterality affected these variables. Analysis of Variance revealed that children with crossed laterality were significantly impaired in more settings than those with either right or left dominance (p=0.04). The results also revealed that crossed laterality could lead to more symptoms of ODD. Children with ADHD exhibited significantly more cross lateral dominance than typically developing controls. Ear dominance seems to be a more accurate predictor of ADHD symptoms than handedness, footedness and/or eye dominance. This study revealed that lateral dominance could discriminate between children with ADHD and a control group without ADHD symptoms. It is, therefore, recommended that lateral dominance assessments be included in the diagnosis and treatment of children with ADHD.

Keywords: ADHD, laterality, handedness, earedness, dominance