As the public perception of marijuana’s risks softens, a primary question complicating the drug’s newly destigmatized status is its effect on young people, especially in terms of brain development.
Marijuana accounts for 90 percent of illicit drug use among American teenagers, according to the 2017 book Is Marijuana Harmful?, written by Bradley Steffens for the educational publisher ReferencePoint Press. In 2015, more than one-third of twelfth-graders in the United States used cannabis at least once, a rate two and a half times higher than the general population.
Steffens noted that “studies show the use of marijuana affects memory, thinking, and behavior in adults; however, the symptoms are not permanent if a person stops using the drug.” The prognosis for teenagers is more worrying. In 2014, researchers at Harvard and Northwestern universities conducted brain scans of young adults and “found differences between those who used marijuana and those who did not,” specifically in the structure of the nucleus accumbens, which Dr. Hans Breiter of Northwestern called “the core of motivation, the core of pleasure and pain.” And in Melbourne, Australia, scientists at the Murdoch Children’s Research Institute found that “long-term cannabis use is hazardous to white matter in the developing brain.” This “white matter” is composed of cells “that allow different parts of the brain to communicate with each other.”
In Lafayette, California, Dr. Alex Stalcup serves as medical director at the New Leaf Treatment Center, a drug rehabilitation clinic for adults and adolescents. Board-certified in addiction medicine, Stalcup trained as a pediatrician at the University of California, San Francisco, and was medical director at the Haight-Ashbury Free Medical Clinic between 1987 and 1990. At New Leaf, Stalcup has worked with marijuana-dependent teenagers for “a little more than 20 years.” His patients consist of affluent, East Bay, teenagers, whose parents bring them to his outpatient rehab, and of “kids who are poor that are sent to us by probation or parole or the courts for assessment or possibly treatment.”
Stalcup described his adolescent patients as “bong-in-the-backpack kids. They’re sitting in high school in the back of the room, and they reek of weed, and somebody checks their backpack and finds a bong. A lot of those kids are referred to us.” Usually, these teenagers “wake up in the morning, and first thing, they roll over and take a bong hit. They take bong hits every hour throughout the day, or they have a vape pen they carry with them to school. So, they’re basically stoned all the time. And they’re not that functional; they just don’t function that well. They don’t do their homework; they don’t do their chores. Their hygiene is bad. The kids they hang out with are not very stimulating. They spend five, 10, or 15 hours a day playing video games. So, basically, it’s a whole marijuana lifestyle, and I think they can live that way, but it certainly does take them from the life that otherwise would be associated with being 17.”
The doctor explained that drugs “are chemicals that activate the pleasure chemistry of your brain. If you overstimulate the pleasure center, like any other part of the brain, it becomes underactive. Whether it’s tobacco or heroin or cannabis, all drugs – if you overdo it, anyway – injure the pleasure center of the brain. You know that you’re in trouble when the amount that used to get you high doesn’t work anymore, and you need to go higher on the dose. That’s a sign that your pleasure system is failing and becoming generally unresponsive to pleasure. Well, the damaged pleasure extends beyond dope,” and before long, adolescent cannabis abusers “don’t get reward from much of anything.” In medical terminology, the inability to feel pleasure is called anhedonia. Marijuana-dependent teenagers experience the condition “as boredom, terrible boredom, nothing interesting, nothing to motivate them. Trying to get these kids to a movie, even, is a big challenge.”
In treating these patients “the first thing we try and do is figure out what else is going on, and it may well be and commonly is that cannabis is the way they cope with a really, really bad situation.” Stalcup estimated that two-thirds of the teenagers at New Leaf suffer from depression. “They cry all the time. They want to die. They sit in their rooms in the dark. They can’t sleep; they have nightmares. They are really hurting pretty bad. They really are having a very hard time. Wouldn’t you smoke a joint?” Cannabis-dependent teens typically “come with a lot of baggage.” Stalcup has noticed that many “have had five homes in five years” or are “being bullied” or have learning difficulties. With girls, “there’s a pretty reliable history of abuse, especially unwanted sexual contact, and they often have associated conditions, like eating disorders or cutting.”
Stalcup asserted that, if the underlying issues aren’t resolved, “taking away the drug use won’t work. It’s counterproductive and may be hurtful.” Still, separation remains the first impulse for many well-meaning adults. In Lafayette and neighboring Orinda, parents often “will have the means to send you away to a boarding school, prep school, or treatment school. Some of these are terrible and really abusive; some of them are pretty good. What the kids I see hate the most is being sent to wilderness camp. They hate that. And then they have to come back and re-enter their drug environment, so as a treatment strategy it’s pretty dumb.”
On the other hand, “treating the co-occurring mental health disorders is often a revelation to everybody, especially the kid himself, who didn’t know he was that depressed. One really important principle of getting sober is that you can’t just abandon your main source of pleasure without leaving a big hole in your life.” To replace cannabis, Stalcup advocates physical activity, explaining that “the pleasure system is naturally activated by sports. They won’t work as well as drugs, ever, really, but they work.”
There are other options. “Studying music, studying drama, studying writing, taking up animals, volunteering in animal care; behind each of these there’s now a body of literature saying that these things really help young addicts get better. So, we get them horse-riding lessons, or we get them a job working at an auto body shop, and the research clearly shows these things repair the damaged pleasure centers. We believe the goal of rehab is to repair the damage to pleasure, so people can begin to take joy in life.” For Stalcup, the hard part “is to get unmotivated kids to try something that they don’t want to do.”
Stalcup affirmed that many of the adolescents at New Leaf “really get better; they really get well, and they blossom.” Even so, he acknowledged that, for some, heavy marijuana use may take a permanent toll, particularly in the prefrontal cortex, which “is the seat of consciousness” and “the part of the brain that evaluates pros and cons and makes decisions. It’s the slowest part of the human brain to develop. Significant development comes at age 18 but continues up to 22 to 24. That process of maturation of the prefrontal cortex is slowed significantly by daily cannabis use.”
Stalcup often encounters patients from earlier in his career “who started smoking pot when they were really young – 12, 13, 14 – and were stoners throughout adolescence. And maybe they’ve gone on and are not using at all, but it’s like they never grew up. You talk to them; it’s like you’re talking to a kid.” In Stalcup’s view, these former addicts are not “simple-minded” and often are “as smart as anyone else,” but they still possess a distinctly “childlike” quality. “In a way, they’re very sweet. We talk about peace and love. I like them very much, but they’re different. I’m not sure if it’s bad or wrong.”
According to Stalcup, it may not be possible to isolate marijuana as the sole cause of the difference, because most teenagers who use weed extensively also employ other drugs, at least occasionally. Similar confounding elements undermine studies examining the effects of cannabis on young people, which often are better able to prove correlation than causation. Virtually any mental abnormality flagged by researchers as a product of adolescent dope abuse may instead have been a catalyst for that abuse.
Regardless, Stalcup is “really optimistic” about his patients’ chances for a return to normalcy. He finds that former “teen stoners” are “easy to spot in their twenties and half their thirties,” but by the time they reach their forties the distinction often fades. Stalcup called this process “maturing out” and speculates that perhaps the brain has been “doing catch-up.”
In San Francisco, a 23-year-old Mission District resident, speaking anonymously, attested that she’s used marijuana daily since the age of 19, with only a few hiatuses, the longest of which was two weeks. She first smoked pot at age 16, but didn’t start using it regularly until two years later, when she was old enough to receive a medical identification card, and became an everyday smoker in college. Now, when she’s at home, she typically smokes one spliff – a hand-rolled cigarette composed, in her case, of about 70 percent tobacco and 30 percent marijuana – an hour. The habit didn’t prevent her, a San Francisco State University graduate, from going to school – though at times she “lost interest” – and doesn’t stop her from holding down a job.
She recognizes now that she began to smoke to self-treat her anxiety and depression, conditions for which she’s never sought psychiatric help. But in high school, “I wasn’t so precise. I wasn’t thinking about it exactly like that. I was just like: this thing’s fun to do; I enjoy myself when I do smoke, so why not?” She noted, however, that as a teenager she often “felt empty,” frequently thought abstractly about death, had “very low self-esteem,” and “didn’t like the way I looked.” Her family was “broke all the time;” her mother was “moody” and “really hard” to be around.
With marijuana, however, “I liked being more silly, and it was something to do.” Ultimately, the experience was profound. The sense of “absurdity” that she felt while high seemed to speak to the irrationality of life in general. In the past, she’d had a tendency of “overanalyzing” herself and others, and her “clearer thoughts” about the world had inevitably led her to a state of panic. Cannabis allowed her to perceive that “everything is silly. It seemed to make more sense.”
Marijuana also made her more talkative. Before smoking pot she’d been cripplingly shy. It was the ordeal of “having to deal with other people” in the acquisition process that’d prevented her from obtaining the drug regularly when she was 16 and 17, before she could go to a dispensary. Cannabis soothed her social anxiety. “In conversations before I smoked weed, people would talk, and if they said something stupid, I would just evaluate that in my head. I would be an observer. But once I started smoking weed, when someone said something stupid or smart or funny, I could respond to that thing.”
Ironically, this new capacity for discussion revived her old habit of overthinking, this time in the form of anxiously dwelling on her failures of self-expression within conversations in which, under the prior conditions of her anxiety disorder, she never would have been able to engage in the first place. In some sense, the end result was “the same.” Even so, “I think I just value participating,” she said. “If I’m saying something, even if I think it’s stupid, at least it was something.”
Sometimes she worries about memory loss. She has moments where “you walk into a room and you’re like: why am I here? It could be because I’m stoned, but it happens to people when they’re not stoned.” She accepted that her capacity to absorb certain kinds of information – especially anything technical or detail-oriented – has been compromised. She’d struggle reading a science textbook. But as a poet and a painter, she said that “it’s a different kind of intelligence I’m valuing. When I’m smoking weed, I can think about a bigger picture, or not think about it, or get lost in it. My attention span can waver, then, and I can bounce from one thing to the other.” She contended that this could be a good thing in art.
While defending cannabis’s anxiolytic properties, she admitted that it’d possibly made her depression worse. “Maybe if I wasn’t smoking, I could feel sad and then go outside and do something which might make it better, whereas if I’m smoking weed I’m more inclined just to stay inside and be at home. I think that’s what it is: pot makes me okay with my feelings.” This can be a much-needed relief, but she sees how it might also prevent her from addressing the root of her problems.
Still, she’ll “probably continue” to smoke. “I just need to get better at knowing the right times to do it. Right now, it’s been a habit for so long that I just do it when I have spare time because I have spare time. I think there should be a difference between me doing it because it’s a habit and me doing it because I feel anxious in the moment. Or I feel like I should at least take the time to acknowledge that I’m feeling anxious and that’s why I want to do it. Sometimes, maybe, I’m doing it, and I’m not thinking about why I’m doing it.”