The growing legal use of recreational and medical cannabis has generated an increased concern for potential side effects from long-term use, particularly regarding problems with memory and sleep. Until now, the effect of cannabis use on sleep and on memory have only been studied separately. Research led by Francesca Filbey, PhD, from the Laboratory of Neuroimaging of Reward Dynamics at The University of Texas at Dallas’ Center for BrainHealth^®, in collaboration with a team from the University of Amsterdam, aimed to fill this gap by testing how sleep impacts memory among cannabis users.

The study, “The role of sleep in the link between cannabis use and memory function: evidence from a cross-sectional study” was recently published in The American Journal of Drug and Alcohol Abuse.

A total of 141 adults with cannabis use disorder (CUD, defined as using cannabis regularly, more than 5 days per week during the past year) and 87 non-current users participated in this study. 

Participants self-reported their frequency of sleep problems within the past week and completed a variety of cognitive assessments that tested their verbal memory, visuospatial learning and memory performance.

Results revealed that the CUD group reported more sleep problems than the non-CUD group, and that this contributed to visuospatial memory problems as well. There was no difference between the two groups in verbal memory performance.

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Lead author Tracy Brown, a UT Dallas psychology PhD student in Dr. Filbey’s lab, stated, “Although sleep is one of the primary reasons people use cannabis, our findings suggest that long-term cannabis use actually results in poorer sleep, which is associated with poorer memory. These findings are useful to inform the consumers, clinicians and policymakers about the therapeutic considerations for cannabis, particularly regarding its use as a sleep aid.”

He added, “For researchers, this study points to the importance of analyzing sleep when evaluating the effects of cannabis on brain health.”

IMAGE CREDIT: Andrea Piacquadio.