Grant: Master's Award: Canada Graduate Scholarships

"With the recent legalization of cannabis in Canada, there are concerns about the long-term effects of regular use. Research shows that heavy cannabis use can impair cognitive functions up to a week after cessation of use. This has implications for safety as attention and motion perception are cognitive functions essential for tasks such as driving. Research has shown that impaired attention can persist even when sober, however, little research has explored the long-term effects of regular cannabis use on attention to motion. A recent study looking at early-onset users showed slower processing and reduced brain responses to moving stimuli suggesting impaired attention to motion. However, how long one needs to regularly use cannabis to elicit such effects is still unknown. The purpose of the following proposal is to explore the long-term effects of cannabis use on attention to motion by comparing non-users, new users, and chronic users in an event-related potential (ERP) study. ERPs look at brain waves that form when exposed to stimuli and can be used to locate brain activity. Participants will complete a visual attention task where they will be asked to attend to moving dots (target) while ignoring distractors. The targets will be presented at two speeds: either slow or fast in either high or low contrast conditions. ERPs will be analyzed in order to compare brain activity of non-users, new and chronic users. It is hypothesized that chronic users will show greater impaired attention than new users and non-users especially in the low contrast and fast conditions. New users are expected to show similar deficits but to a lesser extent. The results of this study will provide a better understanding of the long-term health effects of regular cannabis use."