Very Heavy Pot Use Clouds Mental Function: Study

Yahoo News ^ | 11/29/02 | Very Heavy Pot Use Clouds Mental Function: Study

[Libloather]

Very Heavy Pot Use Clouds Mental Function: Study
1 hour, 58 minutes ago
By Dana Frisch

NEW YORK (Reuters Health) - People who smoked unusually large amounts of marijuana performed worse on tests of mental function than their peers who smoked less pot, even after a 30-day abstinence period, according to a new report.

Heavy users performed worse on 69% of the 35 tasks than light users, though their performances were not "clinically abnormal," the researchers found. The 22 participants were admitted to hospital during the course of the study and submitted to random urine tests to ensure they remained abstinent.

Lead author Dr. Karen Bolla characterized the study group as being "unusual" because of the large number of joints they smoked per week. Heavy users smoked on average 91 joints a week, or about 13 a day, while light smokers smoked an average of 11 marijuana cigarettes a week.

Bolla, who is an associate professor of neurology and psychiatry at Johns Hopkins University School of Medicine in Baltimore, Maryland, said the results cannot be generalized to social smokers or those who use pot for medicinal purposes, because they smoke far less marijuana. The potency might also differ, she said.

"What this study shows is that marijuana can be neurotoxic if you smoke a lot of it," Bolla told Reuters Health. She said this is particularly concerning since the average age of study participants was 22 years old, and the brain is still developing at that age. "You're putting a lot of foreign stuff in there that we don't really know what it does to a developing brain," she said.

The study, published in the November issue of the journal Neurology, found that the mental functions most severely impacted were memory, executive function (overall reasoning and functioning) and manual dexterity.

Bolla writes that these tasks in particular were affected because they are controlled by the hippocampus, prefrontal cortex and cerebellum. These brain areas are densely populated with cannabinoid receptors that attach to THC, the active ingredient in marijuana.

In mice, excessive marijuana use might damage parts of the brain and "knock out certain kinds of neurons," said Bolla. This can lead to receptors in the brain being over-stimulated or under-stimulated, changing their response to chemical messengers in the brain, similar to what might result from a brain injury.

Marijuana is the most widely used illicit drug in the US. An estimated 7 million people use marijuana weekly, according to 2000 data from the US Department of Health and Human Services.

This is only the second study to examine the residual effects of marijuana use after more than a couple of days of abstinence. Dr. Harrison Pope Jr., a professor of psychiatry at Harvard Medical School and author of the other study, found no difference in performance on cognitive tests between heavy marijuana users and "control" subjects.

Pope said in an interview that his "hunch" was that the difference between his results and Bolla's were the "sheer intensity" of marijuana use among the participants in Bolla's study. Heavy users in Pope's study smoked on average 1 or 1.5 joints over the course of a day.

According to Pope, people who smoke a lot of marijuana and start earlier will do worse on tests of mental function. Whether the toxicity of the drug itself is responsible, or factors like being in school less and being unfamiliar with testing or being more impaired initially and turning to pot for that reason, is difficult to know, he added.

SOURCE: Neurology 2002;59:1337-1343.

[tacticalogic]

Like, hey, man, er, uh, you know, like, er, hey, awesome.

It's not er, it's 'ere!.

[Trailerpark Badass]

Heavy users performed worse on 69% of the 35 tasks than light users, though their performances were not "clinically abnormal," the researchers found.

So, I would imagine that this means that the Super Fiends performed better on 31% of the tasks?

[slimer]

Wow man, that's heavy! ;>)

[Johnny Shear]

I have smoked pot since I was 12. I have known a LOT of "Stoners" and even more regular smokers (Like me). During college in the 80's, I saw more drugs and was around more drug abusers than anyone I know.

That being said...

I have NEVER known ANYONE to smoke THIRTEEN FREAKING JOINTS A DAY ON AVERAGE!!!

Yeah, I have seen people (Including myself) smoke 13 joints in a day (Actually, that's not even true...The joints were shared so the total amount of jointage is considerably less) but nothing even CLOSE to an average of 13 joints a day.

Now...Maybe back in the 70's and before, people regularly did this because the pot was about as potent as an aspirin, but since the introduction of high THC pot (Early 80's), NO ONE is smoking 13 a day. Hell, even 11 a week is a LOT!!

This study is a joke.

[HumanaeVitae]

"Very Heavy Pot Use Clouds Mental Function: Study"

The Evidence

[Torie]

I had to cut down on my pot use in law school to the bare minimum, and in fact thereafter. Quite annoying, but it really did impair performance. Really. And even after "recovery" things were sort of sluggish. Really. Frankly, you can't read a paragraph when stoned and remember the beginning by the time you get to the end. About the only thing I could do in that state was math problems (and one doesn't do math problems in law school). Odd.

[wardaddy]

I have seen dreads smoke that much. I could never keep up back in those days when.....

What was this thread about again?

[coloradan]

Very Heavy Pot Use Clouds Mental Function: Study

Incarceration Clouds Mental, Physical, and Spiritual Function: Reality.

[FreedomCalls]

The article speaks of those who are "very heavy" smokers. Not "average smokers," not "heavy smokers," but "very heavy smokers."

Jah, mon, I and I ask your iree Rastaman abou' dis.

[FastCoyote]

"I've never ONCE called Liberteens - mice..."

And I've never called conservatives simpleton morons. So what's your point?

I assume you have access to cans of hair spray. Do you sniff it everyday just because you could if you wanted too? Apparently you guys believe no one has any self control at all, so therefore there should be a law against anything that some stupid arse might shove up his nose. Therefore we should ban Chlorox, amonia, sleeping pills, carrots, peas, aspirin - in fact anything and everything that can be abused.

[CWRWinger]

Is marijuana addictive? Are there any withdrawl problems going cold turkey? Is it easier to quit than smoking?

[wardaddy]

Johnny, how old are you?

I smoked the evolution of pot myself personally. From sh!tty Mex brick weed in 1971 to good Colombian and Jamaican that started coming around in 1973/74....then it was Oxacan foxtail/wife beater long lime green buds (not too shabby) around 1975/76 and then the grand arrival of the first SENSE around summer of 1977 and onwards....sticky skunk bud. I remember my first sensemilla joint....it got 4 or 5 folks buzzed and it lasted longer than usual.

Yes indeed, there was decent pot around in the 70s my man...and lots of black hash as well and honey or red hash oil too. All very very stone-worthy. There was always lots of seedless Thai around as well.

No doubt that hydro pot today has reached esoteric dimensions but good skunk and even good sativa was avaliable as early as the mid 70s.

I gave it up around 82 or 83....life got in the way but i still take a peek at my little brother's weed from time to time. It's great but not exponentially better.

[coloradan]

450 pound bales of marijuana, when placed on people, cause difficulty breathing and may lead to death.

[FourPeas]

They should give a medal to anyone whose lungs could stand 13 joints a day!

I know someone who should get a medal then. It really isn't that difficult if you start when you first wake-up in the morning and keep going until you go to sleep at night.

[wardaddy]

Actually, incarceration provides a clarity unmatched by much outside of combat.

[GRRRRR]

Dave? Open up the door man, it's ME...DAVE!

It's Officer O'Malley and YOUR'E BUSTED...

The most often used word in the English Language: "'ere"...

ELO and Boston, both sides = one party bowl

[Tailback]

This article belongs in the "Duh!" category. Excessive eating causes obesity. Excessive promiscuity leads to STD's. Excessive drinking of alcohol leads to liver problems. Excessive spending leads to bankrupcy. Excessive smoking leads to emphysema.

I'm not ripping on you for posting this Libloather but this is a really stupid article.

[wardaddy]

The only "withdrawal" is mental. You get used to being stoned all day or every night then you will miss it when you're dry....at least I did.

It was rather easy to quit voluntarily when I felt like that phase of limited responsibility in my life had passed but I can rememeber those dry summer months when last years harvest was dwindling and the next autumn one was not yet here and we would go on full alert to procure.

[WaterDragon]

Could be extensive pot use accounts for the very slow learning curve of the Democrats.