420, smoking weed, and drug problems : Marijuana facts

Co-authored by: Jamie Felzer

It’s April 20th, or 4-20, and anyone who smokes marijuana knows what that means – It’s time to smoke weed- a lot of weed!

In honor of this “stoner” holiday, or perhaps in reverence of its implications, I wanted to put together a post that explored some recent findings having to do with the most commonly used illegal substance in the U.S.
These two studies deal specifically with smoking weed, teenagers, and drug problems.

Study 1 – Misconceptions of marijuana use prevalence

An article in the Journal of Studies on Alcohol and Drugs has revealed that most young adults greatly overestimate how many of their peers smoke weed. Teens surveyed believed that 98% of their peers smoked marijuana at least once a year – In reality, only 51.5% off the teens reported actually ever smoking marijuana.

To make matters worse, even though only 15% of the teens reported using once a month or more, the estimate among peers was closer to 65%!!! Since we know that perception of peer behavior affects adolescents greatly, such misconceptions can easily lead to false peer-pressure towards marijuana use.

So next time instead of assuming everyone smokes weed, think again.It’s one of the most commonly used drugs but the notion that everyone smokes weed is simply wrong.

Reference: Kilmer, Walker, Lee, Palmer, Mallett, Fabiano, & Larrimer (2006). Misperceptions of College Students Marijuana use: Implications for Prevention. Journal of Studies on Alcohol and Drugs, 67, pp. 277-281.

Study 2 – Teens reducing use can reduce marijuana dependence risk

This next study dealt with early patterns of weed smoking as possible predictors of later problems use. They followed more than 1500 respondents from adolescence (ages 15-17) into young adulthood (ages 21-24).

The article revealed some interesting overall patterns, but I’ll keep the results short and simple, it is 4-20 after all…

The good news? Teens who reduced their use during the first phase of the study (the teens years) were at a significantly lower risk for marijuana dependence and regular use in early adulthood. This suggests that successful interventions may be effective at reducing later problem use.

The bad news? All marijuana smokers who used at least weekly showed the highest risk for later problems even if they reduced their use… This is not that surprising of a finding though since dependence usually involves regular use.

The bottom line? Reducing marijuana use at any stage will lower your risk for later problem use, but those who find themselves smoking often are most likely to end up in some trouble even if they try to cut down. Knowledge is power, so if you think you might be at risk and are concerned, talking to someone can’t hurt. Knowing marijuana facts can’t hurt either.

Reference: Swift, Coffey, Carlin, Degenhardt, Calabria & Patton (2009). Are adolescents who moderate their cannabis use at lower risk of later regular and dependent cannabis use? Addiction, 104, pp 806-814.

For a different view on 420, see this video:


Gambling on marijuana use makes for bad decisions

I just can’t seem to stay away from the marijuana debate, even given the recent defeat of Proposition 19 that aimed to legalize marijuana in California. This article is a short one, but speaks to some of the cognitive issues associated with marijuana use.

A study (see here) conducted by a Wake Forest University team (Including Doctor Linda Porrino) found that habitual marijuana smokers (those who smoked an average of twice a day for seven years) may be bad at detecting negative outcomes.

The experiment used fMRI scanning technology to examine the brain activity of smokers and controls during the Iowa Gambling Task, which uses four decks of cards. Two of the decks yield large, infrequent, rewards as well as losses. The other two decks yield small, more frequent rewards, and less losses. The first two are considered the “bad” decks, and the latter two the “good” decks, because selecting from the small-gain, small-loss, decks will result in more gain overall. The task is considered a pretty good, if complex, measure of risk-taking, decision making, and loss-discounting.

Marijuana users lose money while controls gainThe take-home result from the study: Not only did marijuana smokers take longer to learn how to maximize their rewards, but their decision-making brain regions seemed to show lower overall responding during the task, meaning they were less active while performing the decisions. And as you can see from the graph on the left, while the controls were able to achieve overall gains, the same was not true for the long-term marijuana users even after 100 repetitions. It seems that marijuana smokers’ brains were not as efficient at detecting losses and responding to them. Maybe that’s why marijuana users are the first to claim that marijuana use has no negative outcomes associated with it…

As usual, it is important to note that since the participants in the study were not randomly assigned to long-term marijuana smoking, it’s impossible to know if these deficits are specifically caused by marijuana use or if they were pre-existing. Nevertheless, these results strongly suggest that individuals who engage in long-term use of marijuana are cognitively distinct from those who don’t. I think that plays into the argument that marijuana legalization would not increase use, because if that’s actually true, then there’s something different about individuals who choose to smoke weed and it is not the legal status that matters. I suspect that in actuality, people who currently choose to smoke marijuana long-term are in fact distinct, in some ways, from some of the people who would take up smoking the stuff if it became legal.

Citation:

Christopher T. Whitlowa, Anthony Liguoria, L. Brooke Livengooda, Stephanie L. Harta, Becky J. Mussat-Whitlowb, Corey M. Lamborna, Paul J. Laurientic and Linda J. Porrino (2004). Long-term heavy marijuana users make costly decisions on a gambling task. Drug and Alcohol Dependence, 76, 107-111.

Nicotine vaccine? It seems addicts would love one!

Okay, so there’s no vaccine for nicotine yet, but if researchers ever find one (like they did for cocaine), this recent study by a group at the University of Pennsylvania suggests that smokers are ready and willing. In fact, more than half of them were biting at the bit!

In case you’re wondering (and don’t feel like reading), the vaccine would work by producing nicotine antibodies in the vaccinated individuals. Those antibodies would attach to any nicotine in the blood and prevent it from doing its thing (binding to nicotinic Ach receptors) thereby making smoking, well… boring. Hopefully, when smokers stop feeling the effect, they’ll stop smoking. Or that’s the thinking behind the whole idea anyway. Given other research that shows that nicotine smoking leads to some pretty strong contextual associations (read: “the environment and other associated stimuli become very rewarding”), I doubt whether the vaccine would work as well as people hope.

But, at least smokers seem willing to try it!