UC San Diego Conducting Virtual Driving-While-High Study

The University of California's Center for Medicinal Cannabis Research is studying driving while stoned.

In an effort to better understand how cannabis use impacts traffic safety, the University of Southern California San Diego’s Center for Medicinal Cannabis Research (CMCR) is partnering with the California Highway Patrol in a study to determine how soon one can safely drive after smoking weed.

If a person consumes cannabis in the morning, how long does their high last? At what point is a person no longer under the influence?

Researchers are examining these questions because traffic safety continues to be a priority in states with legal recreational cannabis, says Tom Marcotte, co-director of UC San Diego’s CMCR.

“They really want to get the impaired driver off the road and not just someone who has THC in their blood,” said Marcotte. “Studies like ours can give people a better idea of how long they should wait before they drive. If you smoked this morning are you impaired throughout the day? Are you impaired for a couple of hours? Or are you not impaired? We're trying to answer that."

The study, involving 180 volunteers, will also analyze how stoned drivers react to common road challenges, like making a left turn against traffic or deciding whether to brake or roll through a yellow light.

Marcotte says stoned drivers often struggle with certaim common driving tasks. Swerving and braking seem to be particularly affected.

Determining if someone is impaired from cannabis is more complicated than alcohol, Marcotte says, in that habitual cannabis users can have THC in their system and not be impaired. 

How does it work?

Following the initial visit, participants return to take a few test-drives in a simulator. Participants are given joints, rolled on site, with varying THC concentrations - or none at all.

The subjects then complete a battery of tests, which include driving simulations, digital performance assessments, field sobriety tests, and fluid tests.

In the performance assessment tests, participants complete tasks on iPads relating to motor control, attention, and memory.

CMCR researchers are paying participants $50 for the initial appointment and $180 when they come back for their full day assessment.

Comments
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West hippie
West hippie

I know when I smoke pay more attention as to how to get home! When I drank I dont remember how I got there safely!!! Its the couch lock I wont leave the house with , I know I could drive but will not!! Drinking since I was 12 riding a Harley Davidson 50cc gear shift on the handlebars, woke up in a ditch doctor said I was drunk was why didnt get hurt? It was the first and last accident always made it home after that. Found weed when I turned 23 , quit drinking every day! I can be myself with weed !

TheWeedBlog
TheWeedBlog

Editor

@420i right?! That would be sooooo interesting for the public to see.

420i
420i

Compairson of alcohol and marijuana for driving would be awesome!

Leah Maurer
Leah Maurer

Editor

@Neon Joint me too! And curious to see if they will do a comparison between these and driving under the influence of alcohol. There is still no good way for law enforcement to test for a DUI due to cannabis consumption so perhaps this will help guide that as well.

Neon Joint
Neon Joint

Awesome study - very cool to see studies like this!! Looking forward to seeing the results!!

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