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Updated: May 15, 2026
07:30
Brain Morphology of Cannabis Users With or Without Psychosis: A Pilot MRI Study
Published on: August 18, 2020
Marijuana use, driving, and related cognitions
Brooke J Arterberry1, Hayley R Treloar, Ashley E Smith
1Department of Educational, School, and Counseling Psychology, University of Missouri.
Summary
Understanding marijuana's effects on driving is crucial. This study found that negative outcome expectancies and perceived danger of driving while high (DWH) reduce the likelihood of DWH and riding with a high driver (RWHD).
Area of Science:
- Psychology
- Public Health
- Transportation Safety
Background:
- Marijuana use is prevalent among young adults.
- Driving under the influence of marijuana poses significant public safety risks.
- Cognitive factors influencing driving decisions after marijuana use require further investigation.
Purpose of the Study:
- To identify cognitive risk factors associated with driving after marijuana use.
- To examine the relationship between marijuana outcome expectancies and driving behaviors.
- To assess the impact of specific cognitions about driving on marijuana use behaviors.
Main Methods:
- Survey administered to 506 college students reporting marijuana use.
- Assessed marijuana outcome expectancies, perceived dangerousness of driving while high (DWH), and social norms.
- Measured likelihood and frequency of driving while high (DWH) and riding with a high driver (RWHD).
Main Results:
- Greater perceived dangerousness of DWH correlated with lower likelihood of DWH and riding with a high driver (RWHD).
- Negative marijuana expectancies were linked to a decreased likelihood of DWH.
- Social norms were associated with a decreased likelihood of RWHD.
- Cognitive predictors reduced the frequency of DWH and RWHD for at-risk individuals.
Conclusions:
- Interventions targeting general negative expectancies of marijuana can reduce DWH and RWHD.
- Educating students on the dangers of DWH may decrease the likelihood and frequency of these risky behaviors.
- Cognitive strategies are vital for preventing impaired driving and riding with impaired drivers.
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