Grant: Master's Award: Canada Graduate Scholarships

Attention-Deficit Hyperactivity Disorder (ADHD) is a highly prevalent neurodevelopmental disorder characterized by persistent patterns of impaired attention and hyperactivity-impulsivity. Executive functioning is adversely affected in ADHD, especially in attentional and impulse control. Many children diagnosed with ADHD use the psychostimulant methylphenidate regularly to improve overall daily functioning, however, there is a lack of data on whether medications will improve performance in tasks of attentional and impulse control. The proposed study aims to measure attentional and impulse control in children diagnosed with ADHD before and after delivering methylphenidate. We hypothesize that the use of methylphenidate will improve the performance in the administered task. Eligible participants will be children diagnosed with ADHD with no history of psychostimulant use. Participants will complete a visual cue task prior to taking methylphenidate to measure baseline levels. In the task, they will be cued by an arrow to one of eight surrounding pools and asked to complete a button press response for a fish target or refrain from responding for a tadpole target. They will then be placed on a six-week drug trial and complete the same visual cue task at the same time of day in lab. A paired-samples t-test will be calculated to compare the mean correct responses in both pre- and post-drug administration conditions. We expect that the mean of correct responses will be significantly higher in the post-drug administration trial, demonstrating medication effectiveness in attentional and impulse control in children with ADHD. The results will be evidence for the use of methylphenidate to target attentional and impulse control deficits in ADHD to improve overall daily functioning.