Detection of Cannabis Impairment With an Eye Tracker (ACS)

Effects of Cannabis on Driver Performance and Eye Movements and Characteristics During Simulated Driving: Feasibility Study

Cannabis is one of the widely used psychoactive substances in the world. With increasing legalization, the prevalence of driving under the influence of cannabis will undoubtedly rise. At present, roadside detection of cannabis intoxication is largely dependent on drug recognition experts who rely on changes in eye movements when impaired. In this regard, use of eye trackers can help to detect impairment in drivers. The purpose of the present study is to determine the feasibility of the use of eye trackers in detecting impairment in participants who smoked a cannabis cigarette.

Study Overview

• Status: Completed
• Conditions: Cannabis Intoxication
• Intervention / Treatment: Drug: Cannabis Sativa

Detailed Description

Participants will attend one study session after determination of eligibility. During this session, they will smoke a cannabis cigarette with 12.5% THC prior to driving a simulator. Driving will be assessed prior to smoking cannabis and at 7 time points after smoking cannabis. Eye tracking measures will also be taken while driving after smoking cannabis. Blood will be drawn for determination of levels of the psychoactive substance THC and its metabolites. Saliva tests, urine tests and subjective tests will also be performed at various times points after smoking cannabis.

• Study Type: Interventional
• Enrollment (Actual): 10
• Phase: Phase 2; Phase 1

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5S 2S1
      • Center for Addiction and Mental Health

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 19 years to 26 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Weekly use of cannabis (1 to 4 days per week) confirmed by urine point-of-care testing;
• 19-26 years of age;
• holds a class G or G2 Ontario driver's licence (or equivalent from another jurisdiction) for at least 12 months;
• Willing to abstain from using alcohol for 48 hours and cannabis for 72 hours prior to the study session;
• Willing to abstain from all other drugs not prescribed for medical purposes for the duration of the study;
• Provides written and informed consent.

Exclusion Criteria:

• Urine toxicology screens negative for cannabis upon eligibility assessment;
• Diagnosis of severe medical or psychiatric conditions;
• Females: Pregnancy or breastfeeding;
• Meets criteria for Alcohol or Substance Dependence (current or lifetime) (DSM-IV);
• Is a regular user of medications that affect brain function (i.e., antidepressants, benzodiazepines, stimulants);
• First-degree relative diagnosed with schizophrenia.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Screening
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Cannabis sativa; a 750 mg cannabis cigarette with 12.5% THC	Drug: Cannabis Sativa; 750 mg cannabis cigarette with 12.5% THC; Other Names: Marijuana

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in eye gaze	Measures of eye movement with an eye tracker	baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in saccades	Measures of quick eye movements with an eye tracker	baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in eye fixations	Measure of where the eye is looking with an eye tracker	baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in blinking rate	The number of blinks, measured with an eye tracker	baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in blinking duration	The length of time that blinks last, measured with a eye tracker	baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in blinking speed	How fast the blinking is, measured with an eye tracker	baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in pupil size	The diameter of pupils while driving, measured with an eye tracker	baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in mean speed on the driving simulator	The speed, in km, while driving a driving simulator	baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in standard deviation of speed on the driving simulator	The amount of variation in speed while driving the driving simulator	baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in maximum speed on the driving simulator	The greatest speed obtained on the driving simulator	baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in standard deviation of lateral position on the driving simulator	The amount of weaving while driving the driving simulator	baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in minimum time to collision on the driving simulator	The time needed to collide with the car in front, while driving the simulator	baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in number of collisions	The number of times a car impacts another car while driving the simulator	baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in blood concentrations of delta-9-tetrahydrocannabinol	The levels of the psychoactive component of cannabis, THC, in blood	baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in blood concentrations of carboxy-tetrahydrocannabinol	The levels of the inactive metabolite of THC in blood	baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in blood concentrations of 11-hydroxy-tetrahydrocannabinol	The levels of the active metabolite of THC in blood	baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in saliva THC detection	Detection of THC in saliva	baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in systolic blood pressure	Vital signs	baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in diastolic blood pressure	Vital signs	baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in heart rate	Vital signs	baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in temperature	Vital signs	baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in number of respirations per minute	Vital signs	baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours
Change in Subjective cannabis effects with a visual analog scale	The amount of liking of cannabis from 0 to 100, with 100 being the greatest value	baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

Collaborators and Investigators

• Sponsor: Centre for Addiction and Mental Health
• Investigators: Principal Investigator: Bernard Le Foll, MD PhD, Centre for Addition and Mental Health

Publications and helpful links

General Publications

• Shahidi Zandi A, Comeau FJE, Mann RE, Di Ciano P, Arslan EP, Murphy T, Le Foll B, Wickens CM. Preliminary Eye-Tracking Data as a Nonintrusive Marker for Blood Delta-9-Tetrahydrocannabinol Concentration and Drugged Driving. Cannabis Cannabinoid Res. 2021 Dec;6(6):537-547. doi: 10.1089/can.2020.0141. Epub 2021 Aug 24.

Study record dates

Study Major Dates

• Study Start (Actual): August 15, 2019
• Primary Completion (Actual): November 15, 2019
• Study Completion (Actual): November 15, 2019

Study Registration Dates

• First Submitted: January 16, 2019
• First Submitted That Met QC Criteria: January 18, 2019
• First Posted (Actual): January 23, 2019

Study Record Updates

• Last Update Posted (Actual): December 12, 2019
• Last Update Submitted That Met QC Criteria: December 11, 2019
• Last Verified: December 1, 2019

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Mental Disorders; Chemically-Induced Disorders; Substance-Related Disorders; Marijuana Abuse
• Other Study ID Numbers: 076/2018

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No