Dopes smoke dope.

[Gob]

Young people who smoke cannabis run the risk of a significant and irreversible reduction in their IQ, research suggests.

The findings come from a study of around 1,000 people in New Zealand.

An international team found those who started using cannabis below the age of 18 - while their brains were still developing - suffered a drop in IQ.

A UK expert said the research might explain why people who use the drug often seem to under-achieve.

For more than 20 years researchers have followed the lives of a group of people from Dunedin in New Zealand.

They assessed them as children - before any of them had started using cannabis - and then re-interviewed them repeatedly, up to the age of 38.

Having taken into account other factors such as alcohol or tobacco dependency or other drug use, as well the number of years spent in education, they found that those who persistently used cannabis suffered a decline in their IQ.

The more that people smoked, the greater the loss in IQ.

The effect was most marked in those who started smoking cannabis as adolescents.

For example, researchers found that individuals who started using cannabis in adolescence and then carried on using it for years showed an average eight-point IQ decline.

Stopping or reducing cannabis use failed to fully restore the lost IQ.

The researchers, writing in the US journal Proceedings of the National Academy of Sciences, found that: "Persistent cannabis use over 20 years was associated with neuropsychological decline, and greater decline was evident for more persistent users."

"Collectively, these findings are consistent with speculation that cannabis use in adolescence, when the brain is undergoing critical development, may have neurotoxic effects."

One member of the team, Prof Terrie Moffitt of King's College London's Institute of Psychiatry, said this study could have a significant impact on our understanding of the dangers posed by cannabis use.

"This work took an amazing scientific effort. We followed almost 1,000 participants, we tested their mental abilities as kids before they ever tried cannabis, and we tested them again 25 years later after some participants became chronic users.

"Participants were frank about their substance abuse habits because they trust our confidentiality guarantee, and 96% of the original participants stuck with the study from 1972 to today.

"It is such a special study that I'm fairly confident that cannabis is safe for over-18 brains, but risky for under-18 brains."

Robin Murray, professor of psychiatric research, also at the King's College London Institute of Psychiatry but not involved in the study, said this was an impressive piece of research.

"The Dunedin sample is probably the most intensively studied cohort in the world and therefore the data are very good.

"Although one should never be convinced by a single study, I take the findings very seriously.

"There are a lot of clinical and educational anecdotal reports that cannabis users tend to be less successful in their educational achievement, marriages and occupations.

"It is of course part of folk-lore among young people that some heavy users of cannabis - my daughter callers them stoners - seem to gradually lose their abilities and end up achieving much less than one would have anticipated. This study provides one explanation as to why this might be the case.

"I suspect that the findings are true. If and when they are replicated then it will be very important and public education campaigns should be initiated to let people know the risks."

http://www.bbc.co.uk/news/health-19372456

[dales]

i forgot the question

[rubato]

I think it might either be correlation or a more indirect form of causation. The inference that cannabis, by some chemical mechanism, alters the neural structure of the brain is weak, in my opinion.

It might be correlation in that the sorts of developing brains which seek immediate stimulation are the sorts of brains which later on show lower functioning. In a related area they have shown that the best predictor of success in life is the ability to delay gratification. Therefore it is merely a correlation that people who cannot delay gratification smoke pot and people who cannot delay gratification are lower functioning.

It also might be indirect causation in that the learning which happens in that age range is some of the most important in developing higher-functioning thinking processess and that if a significant percentage of time they are 'zoned out' they are missing out on valuable experiences which they cannot remediate later on. All of the hours they were stoned or suffering the aftereffects (which IIR reduced functioning for several days afterwards) represent time lost from learning things they needed. The imprint of experience is brighter, more vivid, recalled more acutely later on when your brain is turned all the way on as opposed to when it is damped down part way.

I recall a character in novel who explained why he almost never drinks alcohol by saying:
"I prefer the intoxiciation of lucidity" Lafcadios Adventures Andre Gide. (It might have been "Straight is the Gate"?)

yrs,
rubato

[dales]

whatever

[Lord Jim]

"I prefer the intoxiciation of lucidity"

On that score, rube is pretty much a teetotaler....

It would be interesting to see if there are any earlier studies for comparison. I'm thinking of this because of the way the potency of the marijuana generally available has so vastly increased since the time when most of us were teenagers. I imagine this would have to have some impact.

[rubato]

All crap. No content.

That's you

[Gob]

All crap. No content.

That's you

Now that's what you call "content"!!

[rubato]

All crap. No content.

That's you

Now that's what you call "content"!!

Look up and read.

Or have someone who can, read it to you?

Moron.

yrs,
rubato

[Sean]

[rubato]

Let's see. I post an intelligent and thoughtful comment.

Dales posts his usual smartass bullshit

Gob, & LJ, post their usual personal hate-crap.

About par for this course.

Now that the scorecard is up to date ...

yrs,
rubato

[dales]

Evidently we're all too stoned to give a stuffed sh-t, rube.

Relax, lite up a fattie and go ball your wife.

[Andrew D]

And after their "eight-point IQ decline," pot smokers' average IQ is still some thirty points higher than that of prohibitionists. Go figure.

[Rick]

And after their "eight-point IQ decline," pot smokers' average IQ is still some thirty points higher than that of prohibitionists. Go figure.

Thanks I always knew I'd turn out alright...