High-potency cannabis products impair memory in various ways, according to new research published in Scientific Reports by researchers in Washington State University.
Although public access to high-potency cannabis products has increased in recent years, federal restrictions still demand that researchers use relatively low-potency products in their research. As such, in the present study, scientists set out to find the effects of high-potency cannabis products using novel methods.
To study the effects of high-potency cannabis products legally, the researchers recruited participants who bought their own products and used them in their own homes, rather than in a lab or a federal property. Participants were not reimbursed for their purchases, although they were given Amazon gift cards in return for taking part in the study.
For the research, the scientists recruited 80 participants who were divided into four groups. Two groups were assigned to use cannabis flower with more than 20% THC content, with one containing cannabidiol (CBD) and one without CBD. The third group vaped cannabis concentrates with more than 60% THC and some CBD, and the last group remained sober.
While on a Zoom call with the researchers, the candidates used their products and underwent various psychological tests to assess their decision-making and memory.
In doing so, the researchers found that decision-making, including risk perception and confidence in knowledge, was unaffected. Moreover, no significant changes were noticed among the participants in memory tests involving temporal order memory- the ability to remember a sequence of events, and prospective memory- the ability to remember to do things at a later time.
The researchers noted however that those who smoked cannabis flower with CBD performed worse than those in the control group on verbal free recall tests. Meanwhile, those who used cannabis without CBD and those that used concentrates performed worse on a measure of source memory- being able to distinguish the way previously learned information was presented.
All three cannabis-using groups scored poorly on a false memory test. In this test, participants were presented with a new word and asked if they had been presented with it before. In this case, cannabis-using candidates were more likely to say they had seen the new word before than those in the sober group.
The researchers were surprised to find however that those who vaped high-potency concentrates performed similarly to those who smoked cannabis flower. This, say the researchers, might be because those on higher-potency products tended to use less of the substance than those smoking flowers, and so ultimately reached a similar level of intoxication.
“There’s been a lot of speculation that these really high-potency cannabis concentrates might magnify detrimental consequences, but there’s been almost zero research on cannabis concentrates which are freely available for people to use,” says Carrie Cuttler, lead author of the study.
“I want to see way more research before we come to any general conclusion, but it is encouraging to see that the concentrates didn’t increase harms.”