Is Weed Melting Your Brain?

Maybe your parents were right about pot.

Are your pot-head friends the brightest bulbs in the box? Maybe they are, but imagine how much brighter they’d be if they weren’t toking away brain cells. Like it or not, how Americans view pot has changed. Twenty-seven states have moved towards decriminalizing cannabis (Hartman, 2021). This has been a significant shift away from the War on Drugs. Teenagers have been consuming marijuana via various methods for decades, and this trend continues into the modern day. Forty percent of 12th graders have smoked pot within the past year, with one in seventeen smoking daily (Johnston et Al. (2018). Considering how many adolescents use pot, how does this impact them long-term?

When researching pot users’ outcomes, the most obvious organ of importance is the brain. So, what does pot use during adolescent years do to cognition? Below I’ll address how it influences the brain, and whether this has any impact on intelligence. How does it influence behavior? Does this materialize into real world situations such as education?

“More research is needed…”

Do to pot being illegal, the amount of research done in the past has been limited. The scientific consensus has been that marijuana negatively impacts the brain, particularly memory. Previous research has been muddled due to how commonly marijuana is used alongside other drugs (National Institute for Drug Abuse, 2018). Smoking pot and drinking alcohol can make it tricky to identify which substances is doing what. Think about it, how many of the stoners you know are teetotalers? Within recent years, the amount of research being done has increased in intensity, via new brain imaging technology.

This field also lacks experimental research, as giving kids pot to smoke and then testing them for brain damage is frowned upon (gee, I wonder why?). Therefore, most data comes from looking at those who’ve used pot in adolescence. This will give us a good understanding how marijuana may impact people’s behavior, and their lives as a result.

What does the new research say?

The long-term effects of pot use during teen years are not understood by the public. Permanent effects would require marijuana to cause changes in the brain. This topic should be given more thought, as research suggests it does cause structural changes to the brain, specifically gray matter (Orr et Al., 2019) . These changes were noted in teens who have only smoked once or twice. Smoking pot increases instances of cortico-cerebellar abnormalities, which play a key role in the nervous system and motor function (Lopez-Larson et Al., 2012). This impact can influence a user’s overall mood and intelligence.

What truly matters is what these structural changes to the brain mean for cognitive performance. Research suggests that high cannabis use during teen years accurately predicts a lower IQ and slower function (Camchong et Al, 2017).  Continuing with the same metric, pot users seem to drop in IQ while non-users maintain or increase theirs over the same period (Meier et Al., 2012). This decline was worse for users who started smoking pot during adolescence. Cognitive decline has been found across five forms of functioning, including memory, processing speed, and verbal comprehension (Meier et Al., (2012). Generally, the research suggests that chronically using pot is detrimental for cognitive performance as demonstrated via multiple metrics.

Baked Behavior

So what? What do these changes mean for pot-heads? Well, changes to the brain cause changes in behavior. Overall, the scientific literature presents that pot users tend to engage in behaviors that are criminal or negative. For example, teachers  reported significantly more behavioral issues in pot users (Ehrenreich at El., 2015). Interestingly, all users have a higher high drop-out rate that does not vary by how much they smoke. Other research found that high marijuana use in adolescence is highly associated with criminal behavior (Brook et Al., 2011). Increased crime applies even to those who decrease their use in later years. This may seem intuitive, of course people who use illicit drugs underage are more likely to be criminals when they’re older. Yet even when adjusting for confounding variables, using pot seems to increase people’s tendency for criminality. From all these measurements, we can tell pot use is heavily associated with undesirable outcomes.

How do these behavioral differences materialize in the real world? The behavioral effects of pot use starting in adolescence are often measured in terms of class.  The general consensus being that heavy marijuana use during adolescence is correlated to a lower quality of life (Brook et Al., 2011, Brook et Al., 2013 and  Zhang et Al, 2016). The same research suggests chronic users of marijuana are considerably more likely to be unemployed. This elicits the stereotypical archetype of the lazy stoner (coincidentally also every stoner I’ve ever met). Another societal standard for success, attending college, is associated with significant lower rates of marijuana use (Terry-McElrath et Al., 2019). Taking this into account, there is a clear difference in socio-economics between pot users and non-users.

Chicken or the egg?

Are these negative outcomes truly a result of marijuana use, or do those prone to poor outcomes tend to use cannabis more often? Jackson et Al,. (2016) suggests that there is a notable difference in IQ between users and non-users before starting. Meaning that those with a lower IQ were more inclined to use marijuana. Pot use being associated with poorer outcomes may partially involve environmental factors. It is incredibly difficult to determine that marijuana is solely responsible for these wide disparities. Although the aforementioned pre-existing IQ gaps have been ruled out by via longitudinal studies (Meier et Al., 2012) . What is more likely, is that early cannabis use is a symptom of environment that further worsens a user’s socio-economic status.

It is logically intuitive that smoking pot as a hobby has monetary costs. Repeatedly buying a product that disrupts a person’s mental state is a net negative on that person’s finances. Job performance, or everyday functioning may be impaired. How much is a person’s time worth? How capable is that person when they’re high? The same could be said for alcohol or an other intoxicate, but that does not alleviate the economic burden marijuana can impose. But of course, if getting stoned is more important to you than retirement, by all means puff away (boomer.mp3).

Conclusion on the Confusion

 Although explaining away all of societal ills on teens using marijuana is a bit much, we know it has a impairing effect. Regardless how good it makes pot-heads feel, it’s well established weed’s not kind on your brain. It’s universally understood that pot changes a teen’s brain for the worse, the only disagreement being how much. It causes a variety of permanent, structural impairments. Negative behaviors are associated with young users, some of which appear universal regardless of how much pot is smoked. These patterns occur in academic environments, of which pot-users participate less in.

So the next time you reach for a blunt, stop and think for a second. Should I be doing this? What else could I be doing with my time right now? Take a look at the people around you. Are we as sharp as we used to be? How much money have we spent on pot recently? Are we more capable young adults if we’re doing pot? If you find yourself struggling to remember anything because of all the pot you’ve done, have I got just the blog post for you.


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