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A newly published study from the UC San Diego School of Medicine found how cannabis impairs one's ability to drive.
According to City News Service (CNS), a two-year study conducted by UCSD's Center for Medicinal Cannabis Research found that at least 50 percent of people with THC in their bloodstream were "impaired" while partaking in driving simulations.
Researchers recruited 191 regular cannabis users to consume cannabis containing different levels of delta-9-tetrahydrocannabinol (the psychoactive compound in cannabis) or a placebo immediately before a series of driving simulations tests over several hours.
The findings were published on Wednesday, January 26, in an online issue of JAMA Psychiatry.
According to the study, the THC group displayed significantly diminished ability on a composite drive score that assessed key driving variables like swerving in the lanes, responding to divided attention tasks, and following a lead car.
However, not all participants in the THC group displayed significantly diminished driving skills compared to the placebo group.
The study found no relationship between pot-smoking blood THC concentration and simulator performance.
"The complete lack of correlation between blood concentrations and driving performance was somewhat surprising. It's strong evidence against developing `per se' driving under the influence statutes," said co-author Robert Fitzgerald.
They wrote that future research should address factors like individual biologic differences, personal cannabis experience, and cannabis administration methods in relation to driving impairment.