Two new studies published online last week in JAMA (Journal of the American Medical Association) Psychiatry provide little support for previous claims that cannabis exposure is significantly harmful to the developing brain.
The first study, which assessed the effects of cannabis exposure on brain volume in sibling pairs, reported that any identifiable differences “were attributable to common predispositional factors, genetic or environmental in origin.” By contrast, authors found “no evidence for the causal influence of cannabis exposure” on brain morphology.
The trial is “the largest study to date examining the association between cannabis exposure (ever versus never used) and brain volumes.”
The study is one of two recent clinical trials to be published recently rebutting the claims of a widely publicized 2014 paper, which alleged that even casual marijuana exposure may be linked to brain abnormalities, particularly in the region of the brain known as the amygdala.
In January, researchers writing in the Journal of Neuroscience reported, “no statistically significant differences … between daily [marijuana] users and nonusers on [brain] volume or shape in the regions of interest,” after researchers controlled for participants’ use of alcohol. Similarly, the most recent JAMA study, “casts considerable doubt on hypotheses that cannabis use…causes reductions in amygdala volumes.”
A second study appearing last week in the journal assessed whether cannabis use during adolescence is associated with brain changes that may be linked to an increased risk of schizophrenia.
While researchers reported finding an association among male subjects who possessed a high genetic predisposition toward schizophrenia, authors reported that no such association existed among male subjects who were at low risk for the disease, or among females in either the high risk or low risk categories. The finding is consistent with the theory that early onset cannabis use may potentially exacerbate symptoms in a minority of subjects predisposed to the disease, but it contradicts claims that marijuana exposure is a likely cause of schizophrenia, particularly among those who are not already vulnerable to the disease.
Munchie Showdown: Pop-Tarts vs. Toaster Strudel
First Alcohol Association Supports Recreational Marijuana
How To Make Firecrackers
Oklahoma Health Department Sued Over Medical Marijuana Restrictions
News6 days ago
Israel Moving to Decriminalize Marijuana Use This Week
Science7 days ago
The Truth About Terps
Health6 days ago
Study Finds Cannabis May Not Be Effective at Treating Chronic Pain
News5 days ago
The DEA Has Released This Year’s Drug Slang Handbook
Movies6 days ago
Top 14 2018 Movies to Watch While High
News6 days ago
Synthetic Marijuana Flooding Florida Prisons
News6 days ago
Michigan Approves 11 New Conditions for Medical Marijuana Program
Business6 days ago
The Weird and Wonderful World of Las Vegas Weed Culture