Cannabis Use Does Not Cause Brain Morphology

In 2014, the Journal for Neuroscience released a study suggesting that recreational marijuana use may lead to previously unidentified brain changes. The release of this study highlighted the importance of research aimed at understanding the long-term effects of low to moderate marijuana use on the brain. However, a very recent study that is set to be published in the journal Addiction, says otherwise.

It's no surprise to us that marijuana use is often associated with motivation, attention, learning, and memory impairments. It makes sense when the plant is commonly used to treat insomnia, anxiety, and PTSD. However, we also know that the entourage effect of cannabinoids and terpenes like pinene can increase focus, or limonene enhancing your mood for coitus. This 2014 Journal for Neuroscience report was also publicized quite a bit, so we're happy to find out from that, "a meta-analysis of 69 separate studies reported that cannabis exposure in adolescents and young adults is not associated with any significant, residual detrimental effects on cognitive performance. The results from a pair of recently published longitudinal twin studies similarly report that cannabis use is not independently associated with any residual change in intelligence quotient or executive function."

The specific study to be published in the journal Addiction, was done by a team of twenty international scientists from Australia, the United Kingdom, and the United States, who assessed the relationship between habitual cannabis exposure and grey matter volumes in seven regions of the brain. The conclusion was that frequent cannabis use does not in fact alter brain structure. The study authors concluded: “This is the largest exploratory analysis integrating brain imaging with self-report cannabis and comorbid substance use data. After correcting for multiple testing, there was no effect of cannabis use on the volume at any subcortical region of interest in young adults or middle-aged males. … In the context of expanding medicalization and decriminalization and the concerns surrounding the consequences of increased cannabis availability, our findings suggest that normal variation in cannabis use is statistically unrelated to brain morphology as measured by subcortical volumes in non-clinical samples.”

Information about the interaction of cannabis, especially research aimed at understanding the long-term effects of it's use remains limited since marijuana is a Schedule 1 Drug on the Controlled Substances Act. With thirty states and the District of Columbia currently having laws broadly legalizing marijuana in some form, we hope the federal levels of government change their policies towards a brighter future.

Read the full report here.

Read about the recent study findings to be published by Addiction, here at the NCBI.

Information courtesy of and National Center for Biotechnology Information.

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