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Completed

NCT Number: NCT03813602

Detection of Cannabis Impairment With an Eye Tracker

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.

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Key information

Age range

19 year–26 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 1 / Phase 2

Primary location

Center for Addiction and Mental Health

Toronto, Ontario, M5S 2S1, Canada

About this study

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.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

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.

Treatment and study plan

Cannabis Sativa

Drug

750 mg cannabis cigarette with 12.5% THC

Other names: Marijuana

Primary outcomes

  1. Change in eye gaze

    Time frame: baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    Measures of eye movement with an eye tracker

Secondary outcomes

  1. Change in saccades

    Time frame: baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    Measures of quick eye movements with an eye tracker

  2. Change in eye fixations

    Time frame: baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    Measure of where the eye is looking with an eye tracker

  3. Change in blinking rate

    Time frame: baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    The number of blinks, measured with an eye tracker

  4. Change in blinking duration

    Time frame: baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    The length of time that blinks last, measured with a eye tracker

  5. Change in blinking speed

    Time frame: baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    How fast the blinking is, measured with an eye tracker

  6. Change in pupil size

    Time frame: baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    The diameter of pupils while driving, measured with an eye tracker

  7. Change in mean speed on the driving simulator

    Time frame: baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    The speed, in km, while driving a driving simulator

  8. Change in standard deviation of speed on the driving simulator

    Time frame: baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    The amount of variation in speed while driving the driving simulator

  9. Change in maximum speed on the driving simulator

    Time frame: baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    The greatest speed obtained on the driving simulator

  10. Change in standard deviation of lateral position on the driving simulator

    Time frame: baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    The amount of weaving while driving the driving simulator

  11. Change in minimum time to collision on the driving simulator

    Time frame: baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    The time needed to collide with the car in front, while driving the simulator

  12. Change in number of collisions

    Time frame: baseline, 15 minutes, 35 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    The number of times a car impacts another car while driving the simulator

  13. Change in blood concentrations of delta-9-tetrahydrocannabinol

    Time frame: baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    The levels of the psychoactive component of cannabis, THC, in blood

  14. Change in blood concentrations of carboxy-tetrahydrocannabinol

    Time frame: baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    The levels of the inactive metabolite of THC in blood

  15. Change in blood concentrations of 11-hydroxy-tetrahydrocannabinol

    Time frame: baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    The levels of the active metabolite of THC in blood

  16. Change in saliva THC detection

    Time frame: baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    Detection of THC in saliva

  17. Change in systolic blood pressure

    Time frame: baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    Vital signs

  18. Change in diastolic blood pressure

    Time frame: baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    Vital signs

  19. Change in heart rate

    Time frame: baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    Vital signs

  20. Change in temperature

    Time frame: baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    Vital signs

  21. Change in number of respirations per minute

    Time frame: baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    Vital signs

  22. Change in Subjective cannabis effects with a visual analog scale

    Time frame: baseline, 5 minutes, 25 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours

    The amount of liking of cannabis from 0 to 100, with 100 being the greatest value

Sponsors and collaborators

Lead sponsor

Centre for Addiction and Mental Health

Other

Registry information

Official study title

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

Acronym: ACS

Important dates

Study start
2019
Primary completion
2019
Study completion
2019
First posted
Jan 23, 2019
Registry last updated
Dec 12, 2019

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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