cannabisnews.com: Long-Term Pot Use Takes Toll on Brain 










  Long-Term Pot Use Takes Toll on Brain 

Posted by FoM on March 05, 2002 at 16:07:41 PT
By Adam Marcus, News Reporter  
Source: HealthScout.com 

Many marijuana users say they smoke pot to help them "take the edge off," so it's no surprise the drug makes the mind a bit hazy. However, smokers who have toked for a long time may cause themselves irreversible brain damage that leads to permanent memory and thinking problems. So says a new study by international researchers who have found the cognitive deficits associated with marijuana use are worse in people with a longer history of taking the drug. 
However, at least one cannabis researcher says the findings don't jibe with a recent study showing that even long-term marijuana use causes no appreciable mental deficits. A report on the findings appears in tomorrow's issue of the Journal of the American Medical Association. More than 7 million Americans say they smoke marijuana at least once a week. Scientists generally agree that pot dulls the mind for about 12 to 24 hours, and users will suffer on cognitive tests until the drug washes out of their system. However, there's less agreement about whether long-term use of marijuana exacerbates these effects. The latest study, led by Nadia Solowij, a researcher at the University of New South Wales in Sydney, Australia, suggests the answer may be yes. Solowij and her colleagues, including scientists in the United States, studied 102 heavy pot smokers seeking treatment for their drug use. The volunteers, mostly young and middle-aged men, took a battery of nine memory, learning and cognition tests. Half reported taking the drug daily or nearly every day for an average of about 24 years. The rest said they had been smoking just as much, but for roughly half as long -- 10 years, on average. The tests included word recall tasks, card sorting, time-lapse estimation, and other standardized exams. All were performed after the subjects had refrained from using marijuana for an average of 17 hours. Long-term users scored worse than short-term users and a control group of 33 non-users on tests measuring recall and attention span, the researchers say. They were able to remember fewer words, retained less and had trouble retrieving information. Short-term smokers generally scored as well as the non-users, although both groups of users had problems noting the passage of time. The deficits were in the "moderate to large range," with the biggest difference in word memorization and recall, says Robert Stephens, a psychologist at Virginia Polytechnic Institute and State University and a co-author of the study. "But it's difficult to translate that into daily functioning." Stephens says those sorts of declines might spell trouble for academic learning or performing a complex task, although there's no evidence of that yet. Joseph E. Manno, a cannabis expert at Louisiana State University in Shreveport, says the new findings are "consistent with what you would expect from a drug that is cumulative." The question, Manno adds, is how significant the deficits become. "Are you really, really dangerous, or are you so sedated that you would never engage in any kind of activity that requires skill?" he asks. However, Dr. Harrison Pope Jr., a Harvard University psychiatrist, says that while the study may be smoke, it's not necessarily fire. It conflicts with a recent analysis he conducted of a group of studies showing that long-term pot smoking made no appreciable dent in seven of eight standard measures of brain function, and had only a minor impact on one learning test. In addition, nearly half of the long-term users in the latest study had also regularly used, been dependent on, or been treated for addiction to alcohol or other drugs, which might have affected their memory and cognitive ability. What's more, says Pope, the pot smokers were all seeking treatment for their habit, while the non-using volunteers were drawn from the community by advertisements. People in treatment programs often have other psychiatric problems, such as anxiety or depression -- and may be taking medication for those conditions -- that can affect their results on cognitive tests. Stephens says his group tried to control for these and other factors, including medication and substance intake. Thus, Pope says, "we cannot say for sure whether the greater deficits in the long-term users are necessarily attributable to their long-term use." In fact, he adds, his own work implies they might not be. One study he helped conduct showed the impact of marijuana on the brain dissolved when smokers had been off the drug for 28 days. "As long as there are substantial amounts of the drug still present, there's no question that impairment exists," Pope says. The active ingredient in pot, THC, hangs around in fat, slowly percolating out of the body and causing memory and cognitive hiccups that can linger for days. "But as to whether it permanently harms the brain, I would say that the jury is still out on that," he says. Source: HealthScout.comAuthor: Adam Marcus, HealthScout News Reporter Published: Tuesday, March 5, 2002Copyright: 2002 Healthscout.com Website: http://www.healthscout.com/Ethan Russo M.D. - Chronic Cannabis Usehttp://www.freedomtoexhale.com/ccu.pdfNerves Need Marijuana-Like Substance http://cannabisnews.com/news/thread9799.shtmlExpanding Our Minds About Pot http://cannabisnews.com/news/thread9698.shtml

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Comment #23 posted by overtoke on March 07, 2002 at 14:00:51 PT:
The real reason for test results
The volunteers, mostly young and middle-aged men, took a battery of nine memory, learning and cognition tests. Half reported taking the drug daily or nearly every day for an average of about 24 years. The rest said they had been smoking just as much, but for roughly half as long -- 10 years, on average.They noted the OLDER GROUP (FOURTEEN YEARS OLDER) scored lower on cognitive tests.Hello? The results would have been the same with any group of people with that difference in age.Example: I'm 28 and have smoked for 10 years. I'm 42 and have smoke for 26 years. It's easy to see that the smoking has no bearing on those particular reults.
HempSense.net
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Comment #22 posted by FoM on March 06, 2002 at 11:40:26 PT
DdC
You asked if it's worth posting and I say yes. If we don't know what is being said we won't know how to say how we feel about it all. It is most definitely for educational purposes only though.
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Comment #21 posted by DdC on March 06, 2002 at 11:35:18 PT
Racist Nazi Fascism Is Not a Medical Condition!
Never can be. From Rayguns Bush monkey test to heart attacks to this latest Reefer Mad Bushit. Burn down the Yellow Journals! Thousands of years of use in India found no adverse long term results. Fascist profits over health is the name of their game. FoM is this garbage really worthy of posting?
Peace, Love and Liberty
DdCInfo exchange: Cannabis
http://www.infoxchange.net.au/ydanews/spring94.htm
"In regard to the moral effects of the drugs, the commission is of the opinion that their moderate use produces no moral injury what so ever..." -Report of the British East Indian Hemp Commission.1894. Around that time one Harry Anslinger, the chief of the U.S. Bureau of Narcotics, found that people were listening with some concern, when he spoke of marijuana (which, by the way, is not a narcotic) as "..the foremost menace to life, health and morals in the list of drugs used in America". Most of this interest may be found in the coincidence of use in America at that time being in the Black and Hispanic populations, who were, in a depressed economy, being seen by the white population as unwanted surplus labour. As his outcries against marijuana advanced, so did Anslinger's career (shades of Joseph McCarthy). The USA Merck Manual of Diagnosis and Therapy 1987
"Cannabis can be used on an episodic but continual basis without evidence of social or psychic dysfunction. In many users the term dependence with its obvious connotations, probably is mis-applied... The chief opposition to the drug rests on a moral and political, and not toxicologic, foundation". Dementia Associated With Alcoholism American Description Diagnostic Criteria Impairment in short- and long-term memory
At least 1 of the following: 
Impairment in abstract thinking 
Impaired judgment 
Other disturbances of higher cortical function 
Personality change 
Memory impairment and intellectual impairment caused significant social and occupational impairments 
Absence of occurrence exclusively during the course of Delirium 
Memory loss followed prolonged, heavy ingestion of alcohol 
Exclusion of all causes of memory loss other than alcoholism Associated Features Learning Problem 
Dysarthria/Involuntary Movement 
Hypoactivity 
Psychotic 
Depressed Mood 
Somatic/Sexual Dysfunction 
Addiction 
Sexually Deviant Behavior 
Odd/Eccentric/Suspicious Personality 
Anxious/Fearful/Dependent Personality 
Dramatic/Erratic/Antisocial Personality Differential Diagnosis Normal process of aging; Delirium; Schizophrenia; Major Depressive Episode; Factitious Disorder with Psychological Symptoms; Alcohol Amnestic Disorder; other causes of Dementia. 
http://www.canjneurolsci.org/21maytoc/alcoholi.htm Alcohol Dementia Directory
http://home.sufia.net/user/outreach/al-d.htm Related Links
http://alcoholism.about.com/health/alcoholism//?once=true& Cannabis Prevents Brain Damage
http://pub3.ezboard.com/fendingcannabisprohibitionwhyitstimetolegalize.showMessage?topicID=24.topicCannabis May Offer Protection Against Tumors
http://pub3.ezboard.com/fendingcannabisprohibitionffffhyperlinked.showMessage?topicID=4.topicCannabis Blocks Irreversible Brain Damage
http://pub3.ezboard.com/fendingcannabisprohibitionffffhyperlinked.showMessage?topicID=3.topicThe Hype Brain Damage in Dead Monkeys
(Rayguns suffocates Bonzo)
http://pub3.ezboard.com/fendingcannabisprohibitionwhyitstimetolegalize.showMessage?topicID=50.topic1968 UK ROYAL COMMISSION, THE WOOTTON REPORT:
"Having reviewed all the material available to us we find ourselves in agreement with the conclusion reached by the Indian Hemp Drugs Commission appointed by the Government of India (1893-94) and the New York Mayor's Committee (1944 - LaGuardia)that the long-term consumption of cannabis in moderate doses has no harmful effects" "the long-asserted dangers of cannabis are exaggerated and that the related law is socially damaging, if not unworkable" 
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Comment #20 posted by freddybigbee on March 06, 2002 at 09:06:24 PT:
Poor Sample Selection
"Solowij and her colleagues, including scientists in the United States, studied 102 heavy pot smokers seeking treatment for their drug use."The sample is seriously flawed. People seeking treatment obviously have some sort of serious problem.To study tokers vs non, you would want to select subjects at random from the population, score their tests, then determine their usage history and analyze scores for various usage categories (non-user, short-term, long-term, light, heavy, etc).To study out-of-control individuals who seek treatment and consider them representative of the population at large is just silly. Did these researchers ever take a college science course?
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Comment #19 posted by Toker00 on March 06, 2002 at 07:47:15 PT
boppy
Your daughter will be at the other end of the spectrum than I was. She needs to apply for Technical Director, or Theatre Manager. I started in theatre by accepting a job my brother-in-law offered me when he was Tech. Director at San Antonio Little Theatre, or SALT, in San Antonio, Tex. Although you have to have a high level of skill to be a Set Carpenter, your daughter will have to be able to do it ALL. Does she have two brains? That always helps. She should love her career. Wait for her first big opening night. The adrenaline rush is incredible.Peace. Realize, then Legalize. 
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Comment #18 posted by boppy on March 06, 2002 at 07:17:41 PT
Off topic....TOKER00
My daughter is graduating from Indiana University with a major in stagecraft and aspects thereof. How did you get involved with stage building? She's starting to look for opportunities. And I agree with you comments too, by the way. If you could take a moment drop me a line at cooldaddyg_98 yahoo.com. Thanks.
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Comment #17 posted by Jose Melendez on March 06, 2002 at 07:03:24 PT:
Cannabis, Cognition, and Residual Confounding 
The findings reported by these leading researchers must be evaluated
               carefully. First, Solowij et al report only an association between lifetime
               duration of cannabis use and impairment at 17 hours since last cannabis
               use and therefore cannot extrapolate from this finding to infer whether
               impairment persists for longer periods. Second, the strength of the
               evidence for an association, even at the 17-hour mark, must be evaluated
               in context with other reports.
 Previous data from Solowij favor the
               possibility of persistent deficits associated with lifetime duration of
               cannabis exposure.6 However, the weight of evidence from other studies
               seems tilted in the opposite direction. For example, a recent meta-analysis
               of neuropsychological studies of long-term marijuana users found no
               significant evidence for deficits in 7 of 8 neuropsychological ability areas
               and only a small effect size (ie, 0.23 SD units; 99% confidence interval,
               0.03-0.43) for the remaining area of learning.7 Another recent study5 from
               our laboratory, published subsequent to this meta-analysis, found virtually
               no significant differences between 108 heavy cannabis users and 72
               controlsscreened to exclude those with current psychiatric disorders,
               medication use, or any history of significant use of other drugs or alcohol
                on a battery of 10 neuropsychological tests after 28 days of supervised
               abstinence from the drug. In addition, no significant associations were
               found between the number of episodes of lifetime cannabis use and any of
               the test scores at day 28 even though the heavy users had smoked a
               median of about 15 000 times over periods ranging from 10 to 33 years.5
               Further analysis of these data for associations between lifetime use and
               performance at day 0 and day 1 of abstinence revealed trends that were
               almost always in the same direction as those reported by Solowij et al,1
               but the effect sizes were much smaller (unpublished data).
Cannabis, Cognition, and Residual Confounding 
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Comment #16 posted by Dan B on March 06, 2002 at 02:02:51 PT:
It Works, FoM
I just clicked on your link, and the pdf file works. Thanks for providing it.Dan B
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Comment #15 posted by FoM on March 05, 2002 at 21:23:50 PT

It wants registration now for the pdf format?
I checked it and it opened before I posted it but now it says you must register. I hope it works for others. Strange.I'll try again. It's open for me now but will it work after I post it? Soon find out.http://jama.ama-assn.org/issues/v287n9/fpdf/jed20003.pdf
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Comment #14 posted by FoM on March 05, 2002 at 21:17:24 PT

JAMA
Thanks puff_tuff! I was just going to post it too. We were thinking along the same lines. Cool!Here's the pdf format.

http://jama.ama-assn.org/issues/v287n9/rpdf/joc11416.pdf
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Comment #13 posted by puff_tuff on March 05, 2002 at 21:06:27 PT

JAMA
This is the study that JAMA publishedCognitive Functioning of Long-term Heavy Cannabis Users Seeking Treatment 
http://jama.ama-assn.org/issues/v287n9/abs/joc11416.htmland this is the JAMA Editorial shredding the studyCannabis, Cognition, and Residual Confounding 
http://jama.ama-assn.org/issues/v287n9/ffull/jed20003.html
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Comment #12 posted by FoM on March 05, 2002 at 20:47:28 PT

If I Have Brain Damage
If I have brain damage it would be because of the legal prescription drugs I took for years. Some of those drugs make you live in your very own twilight zone of unreality in my opinion.
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Comment #11 posted by goneposthole on March 05, 2002 at 20:47:24 PT

Legalize Hemp in all forms
Prohibition does not work.It is obviously taking a toll on the prohibitionist's brain.Pot has been used for thousands of years; that's long-term.
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Comment #10 posted by Rainbow on March 05, 2002 at 20:41:39 PT

Journal of the American Medical Association
And what is really sad is the journal publishing this "scientific" study.I sure wish these folks would referee the science. We are sending the wrong message to our children. Do phony science and get published. Quality does not matter if you support the government view.Really a sad comment.Rainbow 
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Comment #9 posted by Toker on March 05, 2002 at 20:26:42 PT:

im sorry..
The pot must have clouded my typing skills, below i meant ..still HAVEN'T been 100% backed up.
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Comment #8 posted by Toker on March 05, 2002 at 20:22:52 PT:

lets just take a moment..
No, smoking cannabis might not be the healthiest thing in the world, but neither is smoking a cig or drinking a beer. Unless you can show the people real facts on why cannabis cannot be legalized, rather than the obvious truth, which is the government is just afraid of losing money and knows they are unable to monoplize, we don't want to hear anymore of the recent studies which still have been 100% backed up.   peace. relize then legalize
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Comment #7 posted by SpaceCat on March 05, 2002 at 19:51:10 PT

Carl Sagan
Yeah, what a dullard. Not to mention Paul McCartney, Richard Feynman, Louis Armstrong, etc., etc.In the spirit of Toker00, I design and run large computer networks. Just implemented Active Directory (Microsoft's latest plan for World Domination) for a University with 20,000 users, flawless first time.Daily Smoker 22 years.
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Comment #6 posted by PonziScheme on March 05, 2002 at 19:22:34 PT

NORML responds to study
NORML has a press release rebutting the study.
http://www.norml.org/news/index.shtml#story1
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Comment #5 posted by Toker00 on March 05, 2002 at 18:21:12 PT

Bogus, indeed.
"Are you really, really dangerous, or are you so sedated that you would never engage in any kind of activity that requires skill?" he asks.How about NEITHER, you dip. Look. I've smoked Cannabis for thirty years, never been a danger to anyone, execpt a sparring opponent, I have built the foredeck of an HMS ship onstage, live theatre sets and props just like the ones that tour from New York "Broadway" shows, custom homes on the west side of Houston, and if you know Houston, you know we're talking about massive square footage and levels. Daily, I wire, plumb, and build. But I am either labeled DANGEROUS OR UNABLE TO LEARN A SKILL? Well, I be damn. Imagine what I COULD have been.Peace. Realize, then Legalize. 
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Comment #4 posted by mayan on March 05, 2002 at 17:20:45 PT

Another ALF Ad!
The American Liberty Foundation(founded by Harry Browne & Perry Willis) will follow up its CNN "Yard Sign" ad with a FOX News "Intruder" ad. They are trying to reach the conservative crowd by running rtba(right to bear arms)ads. They will eventually cover other issues(hopefully regarding mmj or industrial hemp). Someone here at C-News discussed a similar strategy a while back. We have to reach those on the right to expand our camp! See the ad:
http://www.americanlibertyfoundation.org/second.htm
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Comment #3 posted by FoM on March 05, 2002 at 17:08:30 PT

Test This Way
Have a controlled test. Have 2 people that are 100 percent sober sit down in a room and one will drink a beer and one will smoke a joint. After the joint by one and beer by another is finished check them and see who is impaired. Alcohol for adults is legal. Cannabis is not.
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Comment #2 posted by potpal on March 05, 2002 at 17:02:00 PT

Test me...test me...
Whether long term use of cannabis harms your memory or not, which I strongly disagree with from experience, its not a good enough reason to lock people up, fine them, force them into treatment centers, ruin their careers, take away their homes, put their kids in foster homes, call them criminals/terrorists, kill them, etcetera...might as well do the same to anyone suffering from the long slow terminal degenerative disease called 'aging'...
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Comment #1 posted by mayan on March 05, 2002 at 16:59:54 PT

Bogus Study
In addition,nearly half of the long-term users in the latest study had also regularly used,been dependent on,or been treated for addiction to alcohol or other drugs,which might have affected their memory and cognitive ability.What's more says Pope,the pot smokers were all seeking treatment for their habit,while the non-using volunteers were drawn from the community by advertisements. People in treatment programs often have other psychiatric problems,such as anxiety or depression -- and may be taking medication for those conditions -- that can affect their results on cognitive tests. Stephens says his group "tried"(quotation marks mine) to control for these and other factors, including medication and substance intake. My first reaction to this article was this - the smokers were not allowed to smoke for 17 hours before the tests...after a lifetime of smoking on a daily basis. How can one draw the conclusion that marijuana causes permanent damage to the brain after only a 17 hour refrain? This study is absolutely ridiculous & any thinking person can see that it has no credibility.Furthermore, is the University of New South Wales funded by the state? If so, it would seem that the University has an incentive to produce findings that would satisfy the state(to receive more funding to produce more bogus findings).
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