Cannabis Use, Driving Impaired
Conditions
Keywords
MRI, Cannabis, Driving
Brief summary
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.
Interventions
DRUGCannabis
Participants will be assigned to consume one of the cannabis strains and will complete testing immediately after consumption.
Sponsors
University Health Network, Toronto
Unity Health Toronto
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
25 Years to 59 Years
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in neural activation on fMRI during driving simulation | 30-60 min after cannabis intake vs sober | Neural activation, based on BOLD signal, while completing driving tasks under the influence of cannabis and sober. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Performance on driving simulator | 30-60 min after cannabis intake vs sober | Number of errors while completing driving tasks (e.g. turning, driving straight, speed maintenance, missed stop signs, etc.) under the influence of cannabis and sober. |
| Performance on cognitive tasks | 60-90 min after cannabis intake vs sober | Cognitive test battery to assess various driving-related cognitive functions: attention, working memory, visual-spatial processing, processing speed, etc. |
| Blood plasma concentration levels of cannabinoids | 10 min and 60 min after cannabis intake | Concentration levels of THC and CBD throughout the session duration |
Countries
Canada
Outcome results
None listed