Casual marijuana use may damage your brain

[Sparko]

No, thanks. Unlike yourself I prefer critical engagement with arguments presented.

What a smug smartasss reply.

[Paprika]

Just chill bro and dig the cool tune...

No, thanks. Unlike yourself I prefer critical engagement with arguments presented.

[Paprika]

The covariants, including increased alcohol consumption, age, sex, and cigarette smoking were adjusted for in table 2 of the study. They were never said to diminish the reliability of the differences. Specifically, they said "these differences remained significant after controlling for age, sex, alcohol use, and cigarette smoking". The discussion at the end of the study pretty bluntly says

"The present study demonstrates that, even in young, nondependent
marijuana users, morphometric abnormalities relative to
nonusers are observable, many of which are exposure dependent.
These observations also demonstrate that fundamental relationships
observed in covariance analyses among structural measures
of controls are absent in marijuana users, suggesting that marijuana
use may be associated with a disruption of neural organization"

Statistical significance is really

Secondly, the authors also note that "First, the sample size does not provide power to examine complex interactions such as sex differences."

Next, they're measuring differences in brain density on regions of the brain relating to addiction. And they only control for alcohol...is that supposed to be the only common addiction around?

Lastly, one should actually look at the data instead of merely statistical "significance":

Yes, there's a slight general trend that marijuana use is correlated with increases in GMd in the left nucleus accumbus. But we also observe that there are two instances of 0 marijuana consumption that experience greater change in GMd than most of the people that consume marijuana. Obviously there are other factors in play and these need to be sorted out.

[Darth Xena]

That is not everyone's experience. I do not wish to name who, but I spent about twenty years knowing someone in Florida who smoked every day multiple times and never had a health issue. It was only after this person stopped smoking for a job and turned to the "acceptable" and legal drug of alcohol that health and social issues came up.

I also had another friend who didn't smoke as long, but it was daily and had none of those issues as well.

In fact, now that I think about it, I have known a lot of moderate to heavy pot users and none of them had that issue--- not saying it doesn't happen obviously, but it certainly wasn't my normative experience. I think it made some of them lazy (or as that "study" noted, amotivated) but not all of them.

[Catholicity]

I used to smoke pot daily when I was 18. I can tell you that it will trigger a hacking cough, and breathing problems VERY fast. The smoker just doesn't care because of the high. The next day your coughing crap out of your lungs..... Ugly greenish mucousy crap. DAILY!!! I can't possibly see how this is any good for the oxygen circulation in the blood/ hence the idea that it probably lowers how much you get in your brain.

[Darth Xena]

First time I ever said it :)

[Cow Poke]

the pro gay gene people

I believe this is the first time I have ever seen that specific combination of words.

[Sparko]

You guys are harshing my mellow.

[Darth Xena]

No, sorry, since one cannot know what effect those other variables gave they can guess. A guess isn't an adjustment. The NORML article listed other serious problems.

And the small ample size is a huge problem.

If this were a gay gene study with that small sample the pro gay gene people would never hear the end of it and we all know that is true - whether or not anyone here will admit it.

[Teallaura]

The covariants, including increased alcohol consumption, age, sex, and cigarette smoking were adjusted for in table 2 of the study. They were never said to diminish the reliability of the differences. Specifically, they said "these differences remained significant after controlling for age, sex, alcohol use, and cigarette smoking". The discussion at the end of the study pretty bluntly says

"The present study demonstrates that, even in young, nondependent
marijuana users, morphometric abnormalities relative to
nonusers are observable, many of which are exposure dependent.
These observations also demonstrate that fundamental relationships
observed in covariance analyses among structural measures
of controls are absent in marijuana users, suggesting that marijuana
use may be associated with a disruption of neural organization"

Well, there goes co-variants...

[Bill the Cat]

No actually you are using a fallacy fallacy since it is a perfectly legitimate flaw in the study. One which you would be pouncing on if something similar were promoted as showing as "gay gene." You would MOST certainly be jumping up and down pointing out other relevant factors that could have absolutely zero to do with the gene in question but be a factor in the outcome.

Yet not here.

If I were homosexual, and I believed in those gay gene studies, I would be thinking this smells of unjust weights and measures.

Because it does.

This study doesn't prove a thing, and it is not really intended to. Its intent was to give some leads on areas that would be fruitful intensive study. Yet that is not how people are running with it, and the way it is so uncritically accepted by those who already had a bias in that direction, to me, is rather telling. I believe I am pretty consistent in this regard and would hope that my standards are consistent rather than merely hawking something because of confirmation bias.

It may very well be true, as Paprika pointed out. In fact it would not surprise me if it was. As the NORML article pointed out (which article I do not believe you read as it dealt with this point pretty specifically and showed how it was not fallacious), any "intoxicating" substance likely is not the best thing for a developing brain. Including alcohol. Including Caffeine. Including processed sugars. The last two I believe are far greater threats that pot or alcohol.

In fact, there has already been some studies leading to that conclusion, but in much younger age groups, which is why (at least in part), like alcohol, in Colorado, you must be 21 to buy recreational marijuana. I would have zero issue to making that age older if this study and others like it are confirmed.

(and I would point out that this study was funded by people with a very obvious agenda---- that doesn't automatically mean the conclusions were skewed, but it is also a good idea to follow the money--- big Pharma buys studies to its benefit in the past, and I think it is just being shrewd to keep in mind who the pockets are behind things)

The covariants, including increased alcohol consumption, age, sex, and cigarette smoking were adjusted for in table 2 of the study. They were never said to diminish the reliability of the differences. Specifically, they said "these differences remained significant after controlling for age, sex, alcohol use, and cigarette smoking". The discussion at the end of the study pretty bluntly says

"The present study demonstrates that, even in young, nondependent
marijuana users, morphometric abnormalities relative to
nonusers are observable, many of which are exposure dependent.
These observations also demonstrate that fundamental relationships
observed in covariance analyses among structural measures
of controls are absent in marijuana users, suggesting that marijuana
use may be associated with a disruption of neural organization"

[Teallaura]

As reported, the thing shows a correlation, doesn't claim causation, and clarifies that further study is needed for a definitive answer. Pep never brought up an actual flaw - he addressed interpretation (namely, ours).

Methodologically, the only issue I know of is sample size - but it wasn't much of an issue (control pretty well answers it as far as I can see). I only know about that one because of the interview I saw. No one in this thread has brought up any methodological concerns (interpretation is a different issue - and doesn't constitute a flaw).

Now, if someone wants to bring up an actual flaw, fine - but it's a really silly argument that claims we're ignoring flaws when they haven't even been brought up.

As for it being a hatchet job, it's possibly the worst hatchet job in history. Waxman's 'study' (in reality a lit review) that 'proved' abstinence ed didn't work was a typical hatchet job - it didn't qualify itself at all. I've seen multiple qualifications cited from this study in just the citations from this thread - hatchet jobs don't do that. Biased sources can do decent work - which is why it's fallacious to assume bias = bad work. The thing stands or falls on its own merit - attacking the source when the work is obviously qualified about its limitations is just silly. Does that make it a good study? No - but it does eliminate the hatchet job theory.

So, anyone got an actual flaw for us to examine? BTC is correct that all studies have flaws and the mere claim is no refutation. The issue is how severe is(are) the flaw(s) present and that you determine by looking at each.

And for the record, I've routinely tossed studies that supported my position when I found severe flaws with them - heck, a couple that were marginal and I just disagreed with the methodology (I still hate really small samples even if normally acceptable). And I've accepted ones that I totally disagreed with but found no severe flaws (which, FYI, doesn't make a study right, either!). I didn't bother tearing apart methodology on a maybe - see the first citation - and don't see the point now but if someone wants to point me at an actual problem, I'll go look.

[Darth Xena]

EVERY study has flaws. But putting the word study in quotes is no way to debate its merits. And this is not the only study that links the two either.

[Darth Xena]

A modified tu quoque isn't either...

No actually you are using a fallacy fallacy since it is a perfectly legitimate flaw in the study. One which you would be pouncing on if something similar were promoted as showing as "gay gene." You would MOST certainly be jumping up and down pointing out other relevant factors that could have absolutely zero to do with the gene in question but be a factor in the outcome.

Yet not here.

If I were homosexual, and I believed in those gay gene studies, I would be thinking this smells of unjust weights and measures.

Because it does.

This study doesn't prove a thing, and it is not really intended to. Its intent was to give some leads on areas that would be fruitful intensive study. Yet that is not how people are running with it, and the way it is so uncritically accepted by those who already had a bias in that direction, to me, is rather telling. I believe I am pretty consistent in this regard and would hope that my standards are consistent rather than merely hawking something because of confirmation bias.

It may very well be true, as Paprika pointed out. In fact it would not surprise me if it was. As the NORML article pointed out (which article I do not believe you read as it dealt with this point pretty specifically and showed how it was not fallacious), any "intoxicating" substance likely is not the best thing for a developing brain. Including alcohol. Including Caffeine. Including processed sugars. The last two I believe are far greater threats that pot or alcohol.

In fact, there has already been some studies leading to that conclusion, but in much younger age groups, which is why (at least in part), like alcohol, in Colorado, you must be 21 to buy recreational marijuana. I would have zero issue to making that age older if this study and others like it are confirmed.

(and I would point out that this study was funded by people with a very obvious agenda---- that doesn't automatically mean the conclusions were skewed, but it is also a good idea to follow the money--- big Pharma buys studies to its benefit in the past, and I think it is just being shrewd to keep in mind who the pockets are behind things)

[Sparko]

I'm curious to know: what do you think of my comments about the study?

Just chill bro and dig the cool tune...