Study suggests weed smokers are good at decision-making, struggle with memory recall

A recent study found that potent cannabis use can lead to, uh, what were we saying? Oh, right. Cannabis use has the potential to impair memory function, but won't impact users' decision-making skills.

That's according to researchers at Washington State University, who tested high-potency cannabis by observing 80 volunteers who agreed to purchase and use weed for the purpose of the study, since adult-use marijuana is legal in Washington.

Volunteers were separated into four categories: those who used potent cannabis flower (20% or more THC and CBD); those who used potent cannabis flower without CBD; those who vaped weed concentrates containing more than 60% THC and CBD; and, sadly, those who did not participate in cannabis use of any kind. 

Through a series of cognitive tests observed over Zoom, researchers were able to determine that smoking weed causes impairment of memory, specifically free recall (a psychological term that refers to the ability to remember information in any order), source memory, or being able to recall whereinformation was learned, and false memories, which is simply remembering something as being real in your mind, when in fact it is fabricated or completely made up.

Researchers found that marijuana did not have a negative effect on what is referred to as prospective memory, or one's ability to remember to do things at a later date, like pay bills and fulfill appointments. Cannabis users also performed well when it came to recalling the order events took place. 

Unsurprisingly, the sober group performed better overall when it came to false memory tests than the three test groups that were using marijuana.  

While memory impairment has long been joked about as an unscientific side-effect of cannabis use (see: Dude, Where's My Car?), the study challenged previous findings that suggest weed containing CBD could improve memory. But what the WSU study also discovered was that the weed-toking volunteers did not struggle with decision-making, specifically when it came to risk assessment and confidence, and that weed vape-users and smokers had similar results, despite the difference in potency. 

“Because of federal restrictions to researchers, it was just not possible to study the acute effects of these high-potency products,” lead researcher and WSU psychologist Carrie Cuttler said in a press release. “The general population in states where cannabis is legal has very easy access to a wide array of high- potency cannabis products, including extremely high-potency cannabis concentrates which can exceed 90% THC, and we’ve been limited to studying the whole plant with under 10% THC.” 

So, uh, where do we sign up to participate in further studies?

This story first appeared in Detroit Metro Times, an affiliated publication.

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