Kelly Sagar is a Research Associate of Psychiatry at McLean Hospital/Harvard Medical School where she works in the Cognitive and Clinical Neuroimaging Core and Marijuana Investigations for Neuroscientific Discovery (MIND) Program, under the direction of Dr. Staci Gruber. Kelly received her Master’s in school psychology in 2015 and is currently enrolled in Boston University School of Medicine’s Behavioral Neuroscience PhD program where she is also completing a concentration in transdisciplinary addiction science.
Although cognitive decrements have previously been reported among recreational marijuana (MJ) users, few studies have examined whether medical marijuana (MMJ) patients exhibit similar cognitive issues. As recreational MJ users and MMJ patients often differ in terms of reasons for use, product selection, and age of onset, it is imperative to examine whether cannabis may exert a differential impact on cognition when used for medical purposes, particularly as states continue to pass MJ-related legislation. Accordingly, the current study aimed to assess cognitive outcomes related to MMJ use. Specifically, executive function and verbal memory were examined longitudinally in MMJ patients; baseline assessments were conducted prior to initiation of MMJ treatment and patients also returned for three- and six-month visits. Unique patterns of change were observed across cognitive domains; MMJ patients demonstrated improvements in executive function, but also exhibited evidence of transient verbal learning decrements, which appeared to resolve after patients habituated to MMJ use. Additional research is planned to examine patterns of cognitive performance across additional domains and over a longer course of MMJ treatment. Studies examining potential moderating variables are also an important future step.