DALLAS: Staci Gruber vividly remembers her first hit of marijuana, back when she was in college. It made her so paranoid, she locked herself in a bathroom. She couldn’t decide whether to remain in hiding or to run. But she knew she’d never try pot again.
She didn’t lose interest in the drug, however. Today, she runs the 2-year-old Marijuana Investigations for Neuroscientific Discovery, or MIND, project at McLean Hospital in this suburb of Boston. With cognitive testing and neuroimaging, MIND is conducting a longitudinal study of medical marijuana.
“There’s a lot we don’t know about long-term effects, and that’s what I’m here to find out,” Gruber said.
Gruber, 49, has already made her mark on the field.
She ran a small study, published in 2013, that found teenagers and young adults who smoked marijuana were more likely to exhibit impulsive behavior than their peers and were more likely to have certain changes in the brain’s white matter. A followup study found that those changes could reorganize brain regions associated with inhibitions. This year, Gruber’s research team also found that chronic recreational users of pot had poorer cognitive and executive functioning, particularly if they began using marijuana as teens.
MIND’s current work involves adults who are legally permitted to use marijuana-based products for medical conditions. The researchers are particularly interested in the non-psychoactive components of the marijuana plant, such as cannabidiol, an ingredient in many preparations of medical marijuana.
“We have this one word, marijuana, which we think means every part of the plant, and it doesn’t. The cannabinoids I study aren’t even the ones that get you high,” Gruber said. “But whether you’re for medical marijuana or against it, what we really need is information.”
Marijuana has been studied before. But previous research has focused on the cognitive effects of smoking pot recreationally. Earlier studies of medical marijuana have looked mostly at efficacy — how well it treats symptoms of conditions like multiple sclerosis, cancer, and HIV/AIDS.
Gruber and her colleagues, by contrast, are trying to determine the long- and short-term impact of medical marijuana on cognition, brain structure and function, quality of life, sleep, and other clinical measures.
“[This] is a primary concern for patients considering cannabinoid treatment, and it may have implications for public policy,” Gruber said…