Teenage Marijuana Use Lowers IQ?

A recent study shows a link between heavy marijuana use and a decrease in IQ:

http://abcnews.go.com/blogs/health/2012/08/27/teenage-marijuana-use-may-hurt-future-iq/

 

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So what? At least they won't be driving into a tree.

 

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That about sums up my thoughts on the subject.

 

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I don't think that I entirely believe it, at this point. My guess is that future studies will show that things are more complicated.

In my opinion, whatever "stoner" stereotypes might exist out there typically refer to the behavior of people who are currently or recently stoned. Being stoned does reduce a person's cognitive acuity while they are stoned, in some ways at least. People high on marijuana might conceivably have greater ability in some specific tasks, such as music. Marijuana is traditionally associated with musicians -- just think 'jazz'. I suspect that's true with visual artists too. It's conceivable that being stoned raises perceptual acuity and creativity across the board, while simultaneously reducing verbal abstract-cognitive abilities.

There may be a selection effect at work here as well. Some of the kids who were smoking pot heavily and who showed IQ declines might have been experiencing different sorts of problems (motivational, emotional, psychiatric or whatever) that can show up as lower scores on performance tests, even if the person's underlying intelligence is unimpaired. Correlation isn't always the same thing as causation.

In other words, heavy pot smoking might conceivably be a behavioral symptom of problems of a different sort. I think that we see that happening with alcohol abuse. Individuals with alcohol problems are often statistically more likely to have psychiatric problems and criminal histories. The question then is whether the alcohol is actually causing those performance defects, or whether the alcohol use might sometimes just be an individual's attempt to self-medicate or to escape from the suffering associated with a deeper underlying difficulty.

And just obviously, kids who are smoking pot heavily during their school years aren't likely to do as well as their peers in school, which is apt to show up in the later course of the individual's life. He or she will be less likely to attend a university, or is more apt to attend a less-selective school. I think that I've read that schooling has been shown to be able to move people's IQ scores (which is probably reason to question how closely these numbers capture innate cognitive abilities, as opposed to trained problem-solving skills).

But finally, and this is probably the one that's most persuasive to me personally, what this study reports doesn't match my own experience. I've met quite a few very-bright people here in Silicon valley, scientists, engineers, business-people, attorneys and whatnot. And in conversation, many of them have mentioned that they used to smoke lots of marijuana, back in the day. (I know that I sure did.) If anything, I think that I associate a preference for marijuana with higher intelligence, while I associate preference for alcohol with lower intelligence. (But again, that association of alcohol with more aggressive low-life-ism is likely more correlation than causation.)

 

The weight of scientific and clinical evidence suggests that long-term drug use exert mostly negative effects on creativity. Just because writers, artists, actors, musicians, or even scientists may write about their experience with drugs does not necessarily mean that drugs are essential for the creative process.

How could cannabis alter the teenage brain?

Weedsters may be laidback when they’re stoned, but when they’re not, they are amped up assholes. So, I tend to agree with the study below that suggests that adolescent brains are at risk of white matter injury from cannabis. White matter changes rapidly during adolescence. We already know that the nerves that connect teenager’s frontal lobes with the rest of the brain are slower because they don’t have as much white matter as adults in this area. The frontal lobes play a huge role in making logical decisions, impulse-control, organization, and is involved in other functions like emotion. Like the article states, they need to determine if recovery is possible, or if the damage is permanent.

Cannabis and the Adolescent Brain

http://www.ncbi.nlm.nih.gov/pubmed/22669080

 

The word Jazz was originally west coast slang for 'enthusiasm', what a bouncy syncopated rhythm usually inspires...not the mellow passive disposition of the stoner.

 

I have read quite a few scientific papers. This does not read like one of them though. I wonder why not?

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New Zealand is currently rather notorious for bogus cannabis studies, many of which were done in order to further disparage NZ natives (Mauri) who are usually the target group for same. I would suggest the usual political motivation unless proven otherwise.

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Yeah, that describes Carl Sagan and Ronald Regan to a "T", doesn't it? Tell me, oh he who paints with such a broad brush, exactly how many contrary cases does it take to completely negate a hypothesis (like yours)?

(hint - less than 2 and more than 0) I just gave you 2.

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EDIT: I note that they did not control for other substances in the smoke from burning vegetable matter - stuff like carbon monoxide, styrene, anthracine, acetone etc. If you do not control for those you cannot rule them out, and there are a lot of those toxins in any smoke.

 

Well, it would be much simpler if it were just paint by numbers. I, for one, think that cannabis use contributes to mood swings. At what age did Carl Sagan begin to smoke marijuana and who is Ronald Regan?

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Ah - you are not an American then, and seem to have little knowledge of recent world history. Ronald Reagan was the 40th president of the USA. You can learn more about him from Wiki at: http://en.wikipedia.org/wiki/Ronald_Reagan Historically, he was the person credited with bringing down the Soviet Union and the Berlin Wall. Perhaps you have heard of those. I have never heard of anyone describing him as "an amped up asshole".

One uses a variety of paint brushes to do paint by number, none of them very large. It would indeed be much simpler to use just one big brush and one colour of paint, though the results may be somewhat less than the manufacturer designed if you choose to do that.

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I do not know what age Mr Sagan was when he began to consume cannabis, but it did not appear to have damaged his intellect or made him an "amped up asshole". To the contrary, he was a quiet, thoughtful and very well - spoken scientist. Your hypothesis failed that little test I mentioned above, so you have your opinion but nothing by way of science. Dismissing large groups of people with an unproven snide remark may be simple, but it is neither scientific or ethical. The same kind of statements have been made by others regarding individuals sexual or religious preferences, women's rights and minority's physical or intellectual characteristics.

I can agree in general with the statement that young people would be well - advised to abstain from adult vices/habits due to their not being physiologically or intellectually mature enough to weather such. Simply because the liver is generally not mature yet then either.

 

Man, I’ve been getting that a lot lately. I guess harmless wit takes talent. Maybe I should stick with my irresistible sarcasm. Duuuude, it’s Reagan, not Regan. I’m American. In fact, I live in the Emerald Triangle, behind the redwood curtain.

Really? Most of their findings were published in the Proceedings of the National Academy of Sciences. Did you only read the blog? Did you notice that I also linked the original paper? You can purchase the full text through the Oxford Journals.

http://www.ncbi.nlm.nih.gov/pubmed/22669080

Ya? Do you paint, Vincent? Are all of New Zealand’s cannabis studies bogus?

The studies show that people who began smoking marijuana as adults did not show similar cognitive impairment. Based on his writings, it appears that he began using cannabis as an adult.

http://marijuana-uses.com/mr-x/

 

I don't stay up real late at night worrying about my spelling, but yes, I paint quite well, thanks for asking.

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Yeah, once you get known for something it takes a long time for that to wear off - especially when - as NZ has found - your bogus work is taken up by conservative media and put forward as solid reason to rewrite hard - won laws.

I cap the amount of time I spend on one of these topics for practical reasons.

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I have a lot of stuff to do and not a lot of time to do it in, George.

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Interesting - I note that the article in the OP does not say anything about controlling for race or socioeconomic status (although education would be a decent proxy for the latter, I'd think). So one wonders if the sample of smokers isn't heavily comprised of Maoris, who in turn are showing IQ declines for some other, confounding reason.

But yeah, I generally regard any study on marijuana as politically suspect until proven otherwise.

 

Bush?

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Hmm, I wonder…a coincidence or bigmouth.

 

"I had a little friend once, but he don't move no more."

 

Whew, connected causality…good deal!

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It doesn't match my experience either. One of the dumbest things I've ever done is to cut semester units below the minimum 12 in 1966. I didn't start my love affair with cannabis until 1967 while 'visiting' southeast asia.

 

Hey Brucep, :wave:

Criticizing a study from personal experience equates to anecdotal evidence. Got links?

Experts said the new research is an advance because its methods avoid criticisms of some earlier work, which generally did not measure mental performance before marijuana use began.

"I think this is the cleanest study I've ever read" that looks for long-term harm from marijuana use, said Dr. Nora Volkow, director of the National Institute on Drug Abuse, which helped fund the research.

http://en.wikipedia.org/wiki/Long-term_effects_of_cannabis#Memory_and_intelligence

http://medicalxpress.com/news/2012-08-adolescent-pot-mental-deficits.html

http://www.huffingtonpost.com/2012/08/27/teen-pot-use-iq_n_1834392.html

 

It WAS anecdotal evidence. ?. So my anecdotal links are self taught calculus and self taught GR. The possibility the research is 'clean' would be nil in my estimation. It doesn't take a 'recent study' to determine school aged children shouldn't be smoking marijuana before school. I'd be more inclined to think I'm the expert compared to the people who conducted this study. First of all I wouldn't rely on comparative IQ scores to arrive at any conclusions about whether folks lost innate intelligence because they started smoking pot at a young age. Look who funded this research and called it clean. I'd like to check her IQ.

 

http://www.ncbi.nlm.nih.gov/pubmed/22669080

“Anecdotal evidence can have varying degrees of formality. For instance, in medicine, published anecdotal evidence by a trained observer (a doctor) is called a case report, and is subjected to formal peer review. Although such evidence is not seen as conclusive, it is sometimes regarded as an invitation to more rigorous scientific study of the phenomenon in question. For instance, one study found that 35 of 47 anecdotal reports of side effects were later sustained as "clearly correct."

http://en.wikipedia.org/wiki/Anecdotal_evidence#Scientific_context

How old were you when you started smoking weed, Dr. Bruce?

In my opinion, Nora Volkow appears to be extremely intelligent.

[video=youtube;1jLU0oSHs6Q]http://www.youtube.com/watch?v=1jLU0oSHs6Q[/video]

http://www.drugabuse.gov/about-nida/directors-page/biography-dr-nora-volkow

 

I doesn't matter whether she's intelligent or not. The study is 'crackpot' useless other than to say kids shouldn't smoke pot before school. Most grownups would agree with that. The delta IQ isn't a good 'measuring stick' in my opinion. Like who cares?