Driving is a set of complex tasks and requires use of multiple cognitive domains, including attention, planning, and memory. In laboratory studies, the main psychoactive component in cannabis, delta-9-tetrahydrocannabinol (THC), was shown to impair short-term memory, attention, reaction time, tracking, and coordination, resulting, for instance, in significantly more deviations from the lane and increased break latency. Surveys and epidemiological studies suggest that cannabis consumption is associated with increased risks of collision.

The current study aims to evaluate individual driving behavior and performance on various neurocognitive tests and their correlated neural networks while under the influence of cannabis and while sober. The investigators will use the STISIM driving simulator, which is fully MRI compatible, to study brain activation, while participants are performing various driving maneuvers.

The goals of the study are:

1. identify driving performance and patterns in brain activation associated with cannabis exposure and compare them to brain patterns of the same participants while sober;
2. compare participant's performance on cognitive tasks while under the influence of cannabis and sober;
3. look for correlations between concentration of cannabinoids in the participants' blood and their driving performance and performance on cognitive tasks;
4. correlate demographic variables and personal history (e.g. tolerance to drug) with performance and brain activation while driving under the influence of cannabis.

Inclusion Criteria:

• valid driver's license
• have normal or corrected-to-normal vision
• have had prior experience consuming cannabis
• are currently not and have not been regular users in the past 5 years (regular use is defined as at least 1 time per week for at least 1 month)
• prescribed medical cannabis

Exclusion Criteria:

• not fluent in English
• do not meet MRI screening criteria
• use 50 mg/day of morphine equivalents
• history of neurological, neurodegenerative or psychiatric diseases
• any serious sensory or motor impairments
• pregnant women or women trying to get pregnant, or breastfeeding
• serious lung, liver, kidney, and heart problems, including angina, coronary artery disease, and arrhythmia, and Peripheral Vascular Disease
• personal or family history of mental disorders or alcohol or drug abuse or dependence