Grant: Master's Award: Canada Graduate Scholarships

Attention Deficit/Hyperactivity Disorder (ADHD) is a developmental disorder characterized by deficits in attention, hyperactivity and impulsivity. Individuals with ADHD experience significant impairment in many life domains such as cognitive and social functioning, and in their educational attainment. ADHD may also contribute to later externalizing disorders (e.g., oppositional behaviours, substance abuse). Researchers have used neuroimaging methods such as structural magnetic resonance imaging (sMRI) to examine the neural correlates of cognition in ADHD. Several studies have reported that there are structural differences in the prefrontal cortex (PFC) of children with ADHD compared to healthy controls. It is increasingly recognized that specific subregions of the PFC may be differentially involved in cognitive abilities. However, the focus of previous research has been on the macro-architecture of the PFC. Thus, I will use sMRI to examine the neuroanatomical correlates of cognition in ADHD in the dorsolateral, orbitolateral, and ventromedial PFC. Using brain scans of 12 children with ADHD and 10 healthy controls, I will focus on identifying volumetric differences within and between known PFC subregions in these two groups. In addition, I will examine whether subregional brain volumes predict performance on tasks of attention and inhibition. Because previous research has found morphological differences in PFC volumes, I expect that volumes in at least some of the three sections of the PFC will be reduced compared to typically developing children. In addition, because of the deficits observed in children with ADHD, there will be a relationship between performance on cognitive tasks and PFC volume. Results from this project will help to better characterize the underlying neural deficits in ADHD, allowing clinicians to develop better interventions for ADHD. These results will contribute to enhancing the likelihood of better life outcomes in those with ADHD.