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August 2016

Weeding Through Marijuana’s Effects on the Brain

Author Affiliations
  • 1Center for BrainHealth, School of Behavioral and Brain Sciences, The University of Texas at Dallas
JAMA Psychiatry. 2016;73(8):773-774. doi:10.1001/jamapsychiatry.2016.1133

The changes in legislation surrounding cannabis use in the United States and worldwide have placed researchers in a race against time to get ahead of potential pitfalls and quagmires that come with venturing into the unknown of whether cannabis affects the brain. Statistics illustrating that 4.2 million (60.9%) of 6.9 million illicit drug users in the United States with a substance use disorder have cannabis use disorder1 brings this problem to bear. In vivo human neuroimaging research has delivered indicators of divergent brain patterns associated with cannabis use.2 Along with the increasing number of findings demonstrating altered brain structure and function associated with cannabis use is also the mounting need to determine whether these brain anomalies are the cause or the consequence of cannabis use. The implications of the answer to this important question are boundless. If we knew that these alterations precede the onset of cannabis use, we can identify individuals who would be at risk for cannabis use disorders and intervene early on. On the other hand, if observed alterations are a consequence of cannabis use, individuals (and clinicians) could make informed decisions surrounding cannabis use and its applicability. Of timely relevance, this knowledge could guide reasonable, justified, and relevant policies.