Study Looks At Marijuana’s Impact On Brain

INDIANA:  Though marijuana is the most commonly used illegal drug in the country, little is definitively known about its impact on the brain.

A study taking place at Indiana University is designed to help change that.

Clinical psychologist Brian O’Donnell and colleague Sharlene Newman are recruiting current and former marijuana users to participate in a study in which their brains will be analyzed for changes in structure and function.

“From animal studies, there’s reason to believe it (marijuana use) will affect parts of the brain and also the connections between them, and some of our preliminary studies suggest that is the case,” said O’Donnell, a professor in the department of psychological and brain sciences.

The study — funded by a $275,000 grant from the National Institutes of Health — is taking place as marijuana gains acceptance in some parts of the country. Marijuana has been legalized for recreational use in Colorado, Washington state, Alaska and Oregon, and many states now have medical marijuana programs, according to the National Conference of State Legislatures.

 

Marijuana May Be Protective Against Traumatic Brain Injury

CALIFORNIA:  Based on a survey of patients with traumatic brain injuries, a group of Los Angeles Biomedical Research Institute researchers found those who tested positive for tetrahydrocannabinol (THC), the active ingredient in marijuana, were more likely to survive than those who tested negative for the illicit substance.

We surveyed 446 patients who were admitted to a major urban hospital with traumatic brain injuries between Jan. 1, 2010, and Dec. 31, 2012, who were also tested for the presence of THC in their urine. We found 82 of the patients had THC in their system. Of those, 2.4% died. Of the remaining patients who didn’t have THC in their system, 11.5% died.

While most – but not all – the deaths in the study can be attributed to the traumatic brain injury itself, it appears that both groups were similarly injured. The similarities in the injuries between the two groups led to the conclusion that testing positive for THC in the system is associated with a decreased mortality in adult patients who have sustained traumatic brain injuries.

 

Casual Marijuana Use Linked To Brain Changes

MASSACHUSETTS: Using marijuana a few times a week is enough to physically alter critical brain structures, according to a new study published Tuesday in The Journal of Neuroscience.

“Just casual use appears to create changes in the brain in areas you don’t want to change,” said Hans Breiter, a psychiatrist and mathematician at the Northwestern University Feinberg School of Medicine in Chicago, who led the new study.

There is actually very little research on the potential benefits and downsides of casual marijuana smoking — fewer than four times a week on average.

In his study, done in collaboration with researchers at Harvard University, scientists looked at the brains of 20 relatively light marijuana users and 20 people who did not use it at all. All 40 were college students in the Boston area.