WSU researchers use Zoom to study pot potency

Jul. 13—With the help of Zoom, Washington State University researchers have gained new insights into the immediate effects smoking a joint has on memory.

WSU psychologist and lead author on the study, Carrie Cuttler, said the teleconferencing software provided researchers a rare opportunity to investigate the effects of high-potency products commonly used in states where recreational use of the drug has been legalized.

As the substance continues to be tightly regulated by the federal government, Cuttler said research has been hobbled by a raft of restrictions. Among these is a rule that researchers may only use cannabis from a single source through the National Institute on Drug Abuse, which has a much lower potency than what is typically purchased on recreational markets.

However, through the use of Zoom and the recruitment of experienced cannabis users who purchased and imbibed their own high-potency products in their own homes and in a state where it is legal, Cuttler said they were able to circumvent these rules. She stressed participants were not compensated for their purchase, but were compensated for their time with Amazon gift cards, which notably cannot be used to purchase cannabis products.

"We looked at people using cannabis from a recreational dispensary that they purchased themselves using their own funds, then self-administered in their own homes, off federal property," she said. "We simply observed them over Zoom video chat and then we administered a series of memory tests after they've used one of three different high-potency cannabis products or remained sober."

Cuttler said THC, or tetrahydrocannabinol, is the component in cannabis that is largely responsible for the intoxicating effects of the drug. Cannabis that has been federally approved for research has a potency of around 6 percent THC, Cuttler said, but high-potency flower products exceed 20 percent THC and cannabis concentrates can range anywhere from 50 percent to 90 percent..

For the study, Cuttler said participants who were not a part of the sober control group were split into three categories. One smoked high-potency flower with at least 20 percent THC. Another group used a similar product that also included at least 0.7 percent CBD, another ingredient in cannabis that does not produce a high but has been indicated in some previous studies to help protect against memory impairment. The third group smoked high-potency cannabis concentrate that exceeded 50 percent THC that also included CBD.

While few would be surprised to hear smoking cannabis has an acute effect on memory, the details of how those effects manifest is more complicated than it may seem.

Cuttler said researchers found no detrimental effects on prospective memory or temporal order memory. She described prospective memory as "our ability to remember to do things at a later time," like a dentist appointment or remembering to take medication. Temporal order memory is associated with a person's ability to recall the precise sequence of previous events. She said cannabis also had a negligible effect on the user's performance on decision-making tests.

However all of those who smoked cannabis for the study showed a stronger susceptibility to false memory. For this measure, researchers presented them with a list of words that had been presented earlier in the study. When those from the cannabis-using groups were given a new word, they were more likely to answer that it had been a part of that list.

Cannabis users — but particularly those who smoked both THC and CBD — also struggled with a form of memory called free recall. When presented with a group of written words and pictures, they were able to remember fewer pictures and were more likely to mix up whether the subject was presented as a word or as an image.

Perhaps the biggest revelation in this study, Cuttler said, was that there was little difference in the level of impairment recorded in those who smoked flower, and those who smoked the much higher-potency cannabis concentrates. She said this may help assuage fears that these products may actually amplify the detrimental effects of smoking cannabis — and she has a suspicion as to why this may be.

"We found no differences in the cognitive test performance in the groups that used those two products and we think it's because they actually use less product." Cuttler said. "Those who are using the concentrate took significantly fewer hits than those using the flower, so they self-titrate this higher potency product."

Jackson can be reached at (208) 883-4636, or by email to sjackson@dnews.com.