Neural Correlates of Driving and Cannabis

Investigating the Neural Correlates of Driving After Medical Cannabis Exposure

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.

Study Overview

• Status: Unknown
• Conditions: Cannabis Use; Driving Impaired
• Intervention / Treatment: Drug: Cannabis

• Study Type: Interventional
• Enrollment (Anticipated): 12
• Phase: Phase 1

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5G 2C4
      • University Health Network

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 25 years to 59 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Cannabis - Jean Guy; A participant will be administered 1g of Jean Guy strain of cannabis.	Drug: Cannabis; Participants will be assigned to consume one of the cannabis strains and will complete testing immediately after consumption.; Other Names: Marijuana
Experimental: Cannabis - Churchill; A participant will be administered 1g of Churchill strain of cannabis.	Drug: Cannabis; Participants will be assigned to consume one of the cannabis strains and will complete testing immediately after consumption.; Other Names: Marijuana
No Intervention: Sober; All participants will complete same tasks sober.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in neural activation on fMRI during driving simulation	Neural activation, based on BOLD signal, while completing driving tasks under the influence of cannabis and sober.	30-60 min after cannabis intake vs sober

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Performance on driving simulator	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.	30-60 min after cannabis intake vs sober
Performance on cognitive tasks	Cognitive test battery to assess various driving-related cognitive functions: attention, working memory, visual-spatial processing, processing speed, etc.	60-90 min after cannabis intake vs sober
Blood plasma concentration levels of cannabinoids	Concentration levels of THC and CBD throughout the session duration	10 min and 60 min after cannabis intake

Collaborators and Investigators

• Sponsor: Unity Health Toronto
• Collaborators: University Health Network, Toronto
• Investigators: Principal Investigator: Tom Schweizer, PhD, Unity Health Toronto

Study record dates

Study Major Dates

• Study Start (Actual): August 8, 2018
• Primary Completion (Anticipated): December 31, 2020
• Study Completion (Anticipated): December 31, 2020

Study Registration Dates

• First Submitted: June 6, 2018
• First Submitted That Met QC Criteria: July 6, 2018
• First Posted (Actual): July 10, 2018

Study Record Updates

• Last Update Posted (Actual): March 23, 2020
• Last Update Submitted That Met QC Criteria: March 20, 2020
• Last Verified: March 1, 2020

More Information

Terms related to this study

• Keywords: MRI; Driving; Cannabis
• Additional Relevant MeSH Terms: Mental Disorders; Chemically-Induced Disorders; Substance-Related Disorders; Marijuana Abuse
• Other Study ID Numbers: 17-206

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No