There are many who still question both the short and long term potential effects of cannabis (marijuana) use on multiple aspects of brain function, and those questions may take decades to fully answer.
However, this study attempted to determine the non-acute effects of marijuana use on associative memory investigated with functional magnetic resonance imaging (fMRI). 20 frequent cannabis users and 20 non-users were matched for age, gender and IQ.Â
Both performance and brain activation were measured in the associated areas. Interestingly, marijuana users demonstrated less activation in brain regions compared to non-users, but they performed normally on the tasks. In addition, no changes in brain tissue composition was found between users and non-users.
Therefore in this study, lower brain activation does not indicate brain impairment, and may not be associated with cognition (thinking) at all.
