[troydavis]

Here's the actual paper. Long-term Cannabis Users Show Lower Cognitive Reserves and Smaller Hippocampal Volume in Midlife: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9426660/

From the abstract:

> We tested the hypotheses that long-term cannabis use is associated with cognitive deficits and smaller hippocampal volume in midlife, which is important because midlife cognitive deficits and smaller hippocampal volume are risk factors for dementia.

> Participants are members of a representative cohort of 1,037 individuals born in Dunedin, New Zealand in 1972–73 and followed to age 45 years, with 94% retention. Cannabis use and dependence were assessed at ages 18, 21, 26, 32, 38 and 45 years. IQ was assessed at ages 7, 9, 11, and 45 years. Specific neuropsychological functions and hippocampal volume were assessed at age 45 years.

> Long-term cannabis users showed IQ decline from childhood to midlife (mean=−5.5 IQ points), poorer learning and processing speed relative to their childhood IQ, and informant-reported memory and attention problems. These deficits were specific to long-term cannabis users because they were either not present or smaller among long-term tobacco users, long-term alcohol users, midlife recreational cannabis users, and cannabis quitters. Cognitive deficits among long-term cannabis users could not be explained by persistent tobacco, alcohol, or other illicit drug use; childhood SES; low childhood self-control; or family history of substance dependence. Long-term cannabis users showed smaller hippocampal volume, but smaller hippocampal volume did not statistically mediate cannabis-related cognitive deficits.

[SamoyedFurFluff]

This associative effect is interesting in that there’s not a causal proven relationship albeit many common alternatives have been ruled out. It could very well be the kind of people who partake in weed were already predisposed to losing iq and developing dementia risk factors for some other abstract reason, and we can use weed smoking as a signal of something else being wrong.

Fascinating stuff tho

[iLoveOncall]

People will really try anything to make it seem like Cannabis is perfectly harmless even in the face of cold hard evidence, it's laughable.

[starkd]

Its not that hard to believe though. When you have used something for a long while, its difficult to face the fact that you may have been doing something to the detriment of your health. I see it as a coping mechanism.

I really don't understand what the allure of cannabis is. For me, an immediate effect was a decline not only in cognitive ability but also short term memory. Like not being able to hold a thought for more than 5 seconds. How is that pleasurable? It should be no wonder long term use trends in the direction of decline. Of course, for older or termininally ill patients, the pain management benefits may be worth the trade-off, but if the choice is living with pain vs. being perpetually stoned, I think I'd try living with the pain as much as long as I can.

(FTR, I am not against legalisation, so no need to accuse me of trying to take away your drug. I just think we need to make these decisions with caution.)

[imustbeevil]

> I really don't understand what the allure of cannabis is.

Everything that exists in reality, from the observable beginning to the projected end, follows a pattern of abstraction that is exact and single. Drugs give you access to "suspension of disbelief" in experiencing fiction that is larger than reality.

> Like not being able to hold a thought for more than 5 seconds.

Not really an effect of cannabis. Heuristically it's more like the opposite, focusing on one thing for hours. The same way people with ADHD take Adderall.

[starkd]

>> Everything that exists in reality, from the observable beginning to the projected end, follows a pattern of abstraction that is exact and single. Drugs give you access to "suspension of disbelief" in experiencing fiction that is larger than reality.

Thats a fancy way of saying it gets you stoned. You can intellectualize it all you want, but its just words. I can think of any number of ways to "suspend my disbelief": try holding your breath, or slapping yourself silly. Try putting your finger in an electric socket. Really, there's no shortage of ways.

[nebulousthree]

Your description of your experience with cannabis is telling. If you're frustrated with not being able to hold a thought for more than 5 seconds, then that might mean that you went into it with expectations of how it should go, and then spent your time being high trying to retain the "control" you had sober and bring those expectations to reality. This is a common mistake. The good parts of cannabis come from letting go of expectations of control. It's in letting go that hyper focused states or creative bursts can happen.

Not everyone is able to "let go" at will, but some can do it intuitively while others may have anxieties regarding control that must be worked through.

[imustbeevil]

> Thats a fancy way of saying it gets you stoned. You can intellectualize it all you want, but its just words.

This is a forum everything is just words. The reality is that not doing things is X and doing things is X+1, and all of you X people are -1.

> I can think of any number of ways to "suspend my disbelief":

Obviously drugs are better than all of those things. What is the argument there? You can jerk off with a knife too, it doesn't feel as good.

[SamoyedFurFluff]

Sorry I didn’t make myself clear. I think it’s entirely possible cannabis causes problems. I’m saying this study has successfully narrowed down reasonable associations to make direct cause more likely. But this also means if it is caused by another factor, we can use weed use as a signal for whatever that other factor is with high confidence. It’s multi use in that way which is helpful to establish. It shows evidence that people who are smokers of weed now either are doing damage to themselves or have potentially significant issues they need to address because something is doing damage.

[red-iron-pine]

It has drawbacks. No one is saying it doesn't, but now we have a gasp on them.

Like, wait until I tell you about how bad alcohol, sugar, or sleep deprivation is for you...

[devwastaken]

IQ statistics is pseudo science. Therefore we can dismiss the study out of hand. Soft sciences need to be able to prove their underlying methodologies, and have so far largely failed to do so. They rely on shifting around numbers and cherry picking data to get specific outcomes.

[gameman144]

> IQ statistics is pseudo science.

The correlation between IQ and general intelligence is one of the more reproducible results in psychology. Is there a different usage of IQ that you're doubting, or are you doubting that correlation itself?

[nebulousthree]

This doesn't really inspire confidence given the recent reproducibility crises.

[gameman144]

Wait, but the IQ/intelligence link is reproducible.

Are you just saying that "most reproducible" is a low bar? (If so, that makes sense.)

[nebulousthree]

Yes, sorry for the lack of clarity. I mean in the same way that infinity+1 > infinity is a trivial difference and only technically true.

[defrost]

Just as something to ponder, this caught my eye:

> The correlation between IQ and general intelligence is one of the more reproducible results in psychology.

and raises the question;

How do you measure | rank 'general intelligence' in a reliable and reproducable manner fully independantly of IQ measures in order to claim a correlation

.. there's just a smattering of chicken and egg there.