Depending on who you listen to, marijuana is either a harmless, non-addictive drug that lets people relax, or a highly-addictive gateway drug to serious addiction. In this report, we cut through the propaganda and reveal the science behind marijuana. How does it really affect your brain? How do different ingestion methods affect marijuana's mood-altering powers? The science behind getting stoned.
In a tiny underground lab on the sprawling campus of Washington State University, Dr. Rebecca Craft carefully administers a controlled dose of tetrahydrocannabinol to an unsuspecting lab rat, then gently places it back in its small plastic cage. “Now we wait for an hour,” says the experimental psychology professor and department chair, who has been studying the effects of marijuana in various test subjects for more than ten years.
Tetrahydrocannabinol—better known as THC—is the infamous compound that causes the “high” feeling associated with using marijuana. Craft’s most recently published study focuses on the differences in the effects of THC on the sexes, a topic that, perhaps surprisingly, has seen very little research thus far. Most people who have looked at the pain relieving effects of cannabis and other drugs have almost exclusively used male rats, as females have cycling hormones that can interfere with results. Yet women not only make up more than half the population, they also experience many more types of pain than men.
Craft and her team gave male and female rats THC over a 9 day period and then observed their responses to a series of pain tests – seeing how much weight they would tolerate on their paw before pulling it away, and how long they would let their tails be dipped in 50°F water. The results were surprising. Female rats were not only more sensitive to the pain relieving drug than males, but they also built a much faster tolerance to the drug, needing more and more to achieve the same pain relief results. “These results may indicate that women have to be more careful in their marijuana usage in order to avoid becoming addicted.”
As one of a small cadre of researchers approved by the federal government to use cannabis, Dr. Craft views the recent legalization of marijuana in Washington and Colorado as a potential boon to a field that has progressed only very slowly since she first began her work. But she’s under no illusions that it will happen overnight. “The wheels of research turn very slowly,” she says as she inspects a rat for initial signs of influence. “My hope would be that not only on the Federal level would they be encourage more research, but also in the state of Washington that there would be more researchers who would pursue this.”
Craft is not alone in her concern over the lack of credible research into a substance that has been growing steadily in popularity and promises to only continue to be more widely used with changes to marijuana laws throughout the country. Denise Walker is Director of the University of Washington’s Innovative Program Research Group, the first in-depth marijuana treatment research center in the country, started in the mid-1980s by renowned marijuana addiction expert Roger Roffman. Walker and her colleagues’ biggest concern is the effect of increased marijuana usage among youths.
They recently developed a unique treatment intervention program—The Teen Marijuana Check-Up—in which they worked with local high school students who were heavy pot users. The teens voluntarily participated in a private, relaxed discussion about their usage and how it was affecting their lives. “It’s very different from how they usually arrive in a treatment setting, which is by force, either from their parents or from the juvenile justice system.” The results of their initial test program were stunning. “In just two visits, particpants reduced their usage, on average, from 39 days in a 60-day period to 32 or 31.”
Walker can’t help but imagine what could be achieved with this voluntary model over the course of a longer intervention. “Often times people are more motivated to change their behavior if it’s within their own free will and this intervention creates that opportunity. Unfortunately right now, looking at this kind of population and this drug from a treatment perspective – we’re like the only game in town.”
As the legalization and medicalization of marijuana gain steam throughout the country, Craft and Walker hope that state and federal government can strike a balance between understanding the effects of this substance better and preventing usage from spiraling out of control. But many users remain somewhat indifferent to the dearth of research out there. Jeff, 38, of Seattle trusts that any new science will only confirm what he already knows. “After twenty plus years of smoking every day and still doing well and feeling great, I mean this can’t be all that bad for me, right?” As the science of marijuana continues to develop, hopefully we can provide better answers to that question.
For more on the legalization of marijuana and its effects, check out the recent First Run Features Release ‘Evergreen’ produced and written by Nils Cowan:
A native of Calgary, Canada who cut his teeth in the documentary industry of Washington, D.C., Nils moved to the Pacific Northwest in 2009 after working on a National Park Service film about Mt. Rainier and falling in love with the area. He has been producing non-fiction content for thirteen years, from broadcast and independent documentaries to museum films and non-profit PSAs. One of his most recent films, 'Beyond the Visible’ which reveals the inner workings and transformational science of the Very Large Array Telescope in New Mexico, was just awarded the 2014 Cine Golden Eagle Award for non-fiction storytelling. Nils lives in Seattle with his wife and two kids.More stories by Nils Cowan