A recently published study has found adult medicinal cannabis patients do not experience adverse changes in either brain morphology (form and structure) or cognitive performance after a year of regular use.
The study sought to establish if there is an association between year-long cannabis consumption for medical symptoms and brain activation during cognitive processes implicated in cannabis use.
Researchers from Harvard Medical School and the McGovern Institute for Brain Research at the Massachusetts Institute of Technology based their study on structural and functional brain imaging (fMRI) data belonging to 57 newly authorized medical cannabis patients and a control group (32 participants) of non-cannabis users at baseline and after one year.
The medical cannabis cohort had received medical cannabis cards for symptoms of depression, anxiety, pain, or insomnia and were aged between 18 and 65 years. Testing at baseline and after one year included working memory, reward, and inhibitory control.
In their findings, the researchers stated:
“The absence of activation differences in this study suggests that adults using cannabis for medical symptoms over 1 year may not experience significant changes within reward, working memory, or inhibitory control domains.”
The study has been published in the JAMA (Journal of the American Medical Association) Network Open.
NORML’s Deputy Director Paul Armentano commented on findings of the study, stating:
“These study’s findings reinforce the fact that medical cannabis use is both safe and effective and they belie longstanding claims that cannabis exposure is either uniquely or significantly damaging to the brain.”
However, it should be noted that cannabis may not be “brain-safe” for teenagers when it is used recreationally and regularly. According to the Centers for Disease Control (CDC), the teen brain continues to develop until around age 25. It says:
“Cannabis use can have permanent effects on the developing brain when use begins in adolescence, especially with regular or heavy use.”
The CDC says using cannabis before age 18 may affect how the brain builds connections for functions such as attention, memory, and learning. This 2021 study suggests that cannabis use during middle to late adolescence may be associated with altered cerebral cortical development.
