Washington State University recently harnessed the power of this video telephony and online chat system to assess the decision-making performance of cannabis consumers; with satisfactory results.

The WSU study1, published in the journal Scientific Reports2, saw a team of researchers observe cannabis consumer behavior via the video conferencing app.

Each study subject underwent a series of cognitive tests after vaping potent cannabis concentrates or cannabinoid-rich cannabis flower that they had purchased from licensed cannabis dispensaries in the legal U.S. State of Washington, D.C.According to the WSU researchers, there was no significant influence on cannabis consumer performance after participating in decision-making tests.

However, the group did acknowledge some minor memory impairments pertaining to distorted memories, free recall, and memory origin."Because of federal restrictions to researchers, it was just not possible to study the acute effects of these high-potency products," said WSU psychologist and the study's lead researcher, Carrie Cuttler. "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."Although the outcome of this study is on-par with the results of past research into low-strength cannabis, the WSU's investigative effort is the second to explore the effects of cannabis concentrates on memory. Moreover, it is just one of just a handful of reviews into cannabis with a tetrahydrocannabinol (THC) potency exceeding 10%. THC is the primary psychoactive substance contained in the green plant.

Cannabis' Impact on Memory: How was the study carried out?

Despite only recently being published, this study into cannabis's impact on memory initially started in 2018. Impressively, Cuttler and her team were able to investigate the effects of potent cannabis without worrying about overstepping federal law.

It's important to note that each study subject purchased their weed (reimbursement was offered in the form of an Amazon gift card) and used the product(s) in their own home, instead of inside a laboratory setting or on federally-owned property. Furthermore, the researchers refrained from handling cannabis themselves. Each participant was aged 21+ and identified themselves as an experienced cannabis consumer, and no previous adverse effects were reported after using the plant.

 To paint a clearer picture of cannabis' impact on memory, researchers divided all 80 participants into four groups:

Two of the groups consumed cannabis flower with a THC content exceeding 20%. However, one of the strains contained the non-psychotropic compound cannabidiol (CBD), whereas the other did not contain any CBD.

• A third group vaped cannabis concentrates that contained more than 60% THC and some CBD.

• A fourth group remained sober.

• The WSU Division of the Office of the Attorney General and the university's research ethics board gave their blessing to the study's method.

Cannabis' Impact on Memory: What were the results?

Contrary to misconceptions surrounding cannabis and its rumoured cerebral impacts, such as brain damage and psychosis – myths that have repeatedly been dispelled3. The researchers found no significant negative connotation(s) between cannabis use and decision-making—examples of the decision-making tests that study subjects underwent include knowledge assurance and risk perception.

Additionally, there were no significant disparities between the sober and cannabis-consuming groups; e.g., no differences were acknowledged regarding remembering to attend appointments and carry out tasks later. Interestingly, those who used weed performed well on 'temporal order memory' — an official definition for the order in which someone remembers a sequence of past events.

Even more interesting was the fact that those who smoked CBD-containing cannabis flower struggled more with verbal free recall tests than the sober group. Aside from the CBD consumers, those who used concentrates also performed unsatisfactorily on a source memory assessment, which involved recalling the origin of learned information.

On the other hand, the results of a false memory test were poor for all three cannabis-consuming groups. This type of test involves the study subject recognizing or recalling a list of semantically related words.

Study authors also noted an unexpected result from the study into cannabis' impact on memory — individuals who vaped high-potency concentrates with more than 60% THC performed similarly to the people who smoked cannabis flower. According to the researchers, this is likely because people who consumed cannabis concentrates were more inclined to self-titrate in an attempt to experience the same "high" as flower consumers.

"There's been a lot of speculation that these 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," noted Cuttler. "I want to see way more research before we come to any general conclusion, but it is encouraging to see that the cannabis concentrates didn't increase harm."

Summary

 Despite being limited due to cannabis' federally illegal status in the United States and across much of the globe, the existing studies into animals and humans present ample evidence that cannabis exposure during development may potentially result in persistent or permanent adverse changes in the brain. For example, based on the results of numerous studies4cited by the National Institute on Drug Abuse (NIH), rats demonstrated problems with memory and learning after being exposed to the mind-altering substance THC before birth, shortly after birth, and during young adulthood. Researchers claim that cognitive changes are connected to functional and structural alterations in the hippocampus.

Results of imaging tests that have been carried out to understand better the plant's impact on brain functioning and structure are widely inconsistent. A handful of studies5hypothesize that regular adolescent cannabis consumption results in modifying brain connectivity and decreased volume of numerous brain regions responsible for a broad scope of integral functions, including memory, learning, and impulse control. Fortunately, this past June, the U.S. Drug Enforcement Administration (DEA) announced6 that it would be prioritizing efforts to broaden cannabis access for research purposes. This means that we could soon be getting more accurate insights into cannabis' impact on memory.

1 https://www.researchgate.net/publication/352932884_Acute_effects_of_high-potency_cannabis_flower_and_cannabis_concentrates_on_everyday_life_memory_and_decision_making%C2%A0

2 https://www.researchgate.net/journal/Scientific-Reports-2045-2322

3 https://www.healtheuropa.eu/leafcann-common-misconceptions-about-cannabis/98605/

4 https://www.drugabuse.gov/publications/research-reports/marijuana/references

5 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3930618/

6 https://www.dea.gov/stories/2021/2021-05/2021-05-14/dea-continues-prioritize-efforts-expand-access-marijuana-research