Study: Marijuana Damages Brain

Study: Marijuana Damages Brain
Posted by CN Staff on April 30, 2007 at 09:08:04 PT
By The Associated Press
Source: Associated Press
London --  New findings on marijuana's damaging effect on the brain show the drug triggers temporary psychotic symptoms in some people, including hallucinations and paranoid delusions, doctors say.British doctors took brain scans of 15 healthy volunteers given small doses of two of the active ingredients of cannabis, as well as a placebo.
One compound, cannabidiol, or CBD, made people more relaxed. But even small doses of another component, tetrahydrocannabinol, or THC, produced temporary psychotic symptoms in people, including hallucinations and paranoid delusions, doctors said.The results, to be presented at an international mental health conference in London on Tuesday and Wednesday, provides physical evidence of the drug's damaging influence on the human brain."We've long suspected that cannabis is linked to psychoses, but we have never before had scans to show how the mechanism works," said Dr. Philip McGuire, a professor of psychiatry at King's College, London.In analyzing MRI scans of the study's subjects, McGuire and his colleagues found that THC interfered with activity in the inferior frontal cortex, a region of the brain associated with paranoia. "THC is switching off that regulator," McGuire said, effectively unleashing the paranoia usually kept under control by the frontal cortex.In another study being presented at the conference, a two-day gathering of mental health experts discussing the connections between cannabis and mental health, scientists found that marijuana worsens psychotic symptoms of schizophrenics.Doctors at Yale University in the U.S. tested the impact of THC on 150 healthy volunteers and 13 people with stable schizophrenia. Nearly half of the healthy subjects experienced psychotic symptoms when given the drug.While the doctors expected to see marijuana improve the conditions of their schizophrenic subjects — since their patients reported that the drug calmed them — they found that the reverse was true."I was surprised by the results," said Dr. Deepak Cyril D'Souza, an associate professor of psychiatry at Yale University's School of Medicine. "In practice, we found that cannabis is very bad for people with schizophrenia," he said.While D'Souza had intended to study marijuana's impact on schizophrenics in more patients, the study was stopped prematurely because the impact was so pronounced that it would have been unethical to test it on more people with schizophrenia."One of the great puzzles is why people with schizophrenia keep taking the stuff when it makes the paranoia worse," said Dr. Robin Murray, a professor of psychiatry at King's College.Experts theorized that schizophrenics may mistakenly judge the drug's pleasurable effects to outweigh any negatives.Understanding how marijuana affects the brain may ultimately lead experts to a better understanding of mental health in general."We don't know the basis of paranoia or anxiety," said McGuire."It is possible that we could use cannabis in controlled studies to understand psychoses better," he said. McGuire theorized that could one day lead to specific drugs targeting the responsible regions of the brain.Source: Associated Press (Wire)Published:  Monday, April 30, 2007Copyright: 2007 Associated Press CannabisNews -- Cannabis Archives
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Comment #18 posted by observer on December 21, 2008 at 13:19:29 PT
Creativity - Schizophrenia - Cannabis
"personality surveys revealed that the artists and poets shared certain traits with schizophrenics." -- this what is being measured? Aspects of creativity? Cannabis is widely used as an aid to creative work. Are these creative aspects of cannabis then conflated with schizophrenic traits? I think this is exactly what is happening. I think creativity is often a threat to obsessive rule followers. 
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Comment #17 posted by BGreen on May 01, 2007 at 21:36:51 PT
Bingo, John Tyler
King's College, London, is the source of the majority of the British "Reefer Madness" propaganda.These aren't peer reviewed studies, instead they are very shoddy "research" that is parroted by the press without ever appearing in a respected medical journal. When a study is published in a peer review journal, it gives other qualified professionals the chance to examine and evaluate the study, lending credibility to those studies which pass the examination of other professionals.The Reverend Bud Green
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Comment #16 posted by John Tyler on May 01, 2007 at 18:04:20 PT
Junk Science
This is just a dressed up version of ridiculous claim that cannabis makes you lazy, crazy and stupid. This has been proven wrong over and over again. I think I have seen that name, Dr. Deepak Cyril D'Souza, in other “studies”. I think he must be on the prohibitionist payroll. Why not study alcohol’s effect on the brain. Doesn’t it kill millions of brains cells? And what about kids bopping soccer balls with their heads, I hear that causes brain damage. Why do these people pick out cannabis to criticize when so much else is worse? Some group is bankrolling this “junk science”.
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Comment #15 posted by Hope on April 30, 2007 at 21:54:52 PT
Brain scans, etc.
We've been through this before. Why don't they just say their brains turned to ashes? Oh...they already used this one. It's the same old lie, like Observer said...just modernized for the day.And, like Whig said, I didn't think you could see psychoses with a brain scan.
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Comment #14 posted by afterburner on April 30, 2007 at 21:53:56 PT
I Wonder What GW Pharmaceuticals Thinks of This
Someone once said, "The city is the mind of man at war with itself." (not PC) This sentiment is surely true of the United Kingdom with legal secret cultivation vs. mind-care professionals protecting their turf. And the United States with one group of scientists believing in mind manifestation (psychedelics) and healing vs. another group devoted to a belief in mimicking psychosis (psychotomimetic). Ditto for US politicians.Here's an earlier article from prohibitionist Indiana, and we all know what member of the US Congress hails from there:Pot Makes You Crazy 
Posted by CN Staff on November 02, 2006
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Comment #13 posted by The GCW on April 30, 2007 at 20:46:15 PT
UK: Cannabis chemical curbs psychotic symptoms...
UK: Cannabis chemical curbs psychotic symptoms, study finds(Coming soon to MAP, -Newshawked by Richard Lake),,2069281,00.htmlJames Randerson, science correspondent Tuesday May 1, 2007 The Guardian 
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Comment #12 posted by BGreen on April 30, 2007 at 12:57:29 PT
This study proves MARINOL = DANGEROUS!
We've said all along that the symbiotic effect of cannabinoids found in the cannabis plant was one of the most important differences between it and the synthetic pills they keep telling us "do what marijuana does but without the negative side effects."You can't legitimately talk about paranoia when you've already declared a two-generation-long war against a certain class of people. Experience tells people that if they're caught with/using cannabis that their lives will be ruined.That's not paranoia, that's a legitimate and logical threat that cannabis partakers were conditioned to expect.If studies on the entire plant aren't going to ever take place, then you can bet that they're GOING to isolate dangerous compounds from this totally innocuous plant, just as they did with coca, just as they did with caffeine ... and just as we've warned time and time again they're doing with cannabis.The Reverend Bud Green
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Comment #11 posted by mai_bong_city on April 30, 2007 at 11:12:03 PT
and yeah, mri
is really no way of measuring - it would have to be some permanent change in the brain - PET scans might show activity in areas of the brain....but these were not pet scans.
i think the whole thing is bunk.
and bravo, museman, on comment #9.
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Comment #10 posted by observer on April 30, 2007 at 11:08:42 PT
Effects of THC painted as 'Damage'
Let's get down to brass tacks here. People use cannabis because of the effects it has. Studies like this re-frame any effects of cannabis as "damage". Studies that paint any mental effect of cannabis as "damage" are bunk. This is old-fashioned reefer madness, with an updated wardrobe and a face-lift.
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Comment #9 posted by museman on April 30, 2007 at 11:06:42 PT
These 'scientifc' studies are deluded. By measuring the mind-altering effects of cannabis, against the mind-numbing reality of the status quo, one could easily assume all manner of 'problems' and 'errant behavior.' When the position of study is negatively based, and biased, can you even credit it at all?My 'hallucinations' prove to me that the existence and imminence of God is of a much higher priority than 'job-functionality' and the abilty to hold down a shallow conversation. My 'paranoia' only came into existence with the WOD.People who are mentally unstable should not watch TV, but smoking cannabis can heal wounded minds -if one does not try to cram the false values of a failed society into the mix -like the 'professions' of psychology and psychiatry do.A wounded mind is one that cannot reconcile the obvious disparity between what the status quo SAYS is true, and what actually is true. The mental confusion that creates depression is a direct effect of social judgement, rejection, and rigorously upheld error. When the 'whole world' laughs and mocks you for your understanding, innocent childlike minds, react badly. If you are rigid in worldy disciplines, with no room for new growth, having your stupidity revealed can be traumatic as well.I am a sovereign being. I have no superior on this earth. No one is qualified to judge me. No one is qualified to describe to me how I should live my life. No one is qualified to compare my experience to their textbook analogies, and no one is qualified to rule over me in any way. Those who attempt to do so are in error.I choose whether I will smoke cannabis, or whether I will smoke camel dung. Camel dung doesn't appeal to me, but then alcohol does appeal to many. Go figure. If anyone wants to become more stupid by consuming a poison such as alcohol. that's their own business. Leave me and my life choices alone. If those choices actually interfere with anyone elses, I'd like to see the facts -other than the same old prohib lameness we are all used to- otherwise just flake off all you false upholders of lies, injustice, and inequality. You're not the boss of me!
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Comment #8 posted by whig on April 30, 2007 at 10:59:30 PT
Complete disinformation
"British doctors took brain scans of 15 healthy volunteers given small doses of two of the active ingredients of cannabis, as well as a placebo."What did the brain scans show?"One compound, cannabidiol, or CBD, made people more relaxed. But even small doses of another component, tetrahydrocannabinol, or THC, produced temporary psychotic symptoms in people, including hallucinations and paranoid delusions, doctors said."Did this have any relationship to the brain scan results?What are your diagnostic criteria?Did the "temporary psychotic symptoms" result in danger to the person or anyone else, or did they resolve safely? Is there a well characterized definition of TPS, and does it differ substantially from temporary confusion?
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Comment #7 posted by whig on April 30, 2007 at 10:52:05 PT
Diagnosing psychosis with brain scans?
That does not even make sense.You cannot brain scan for psychosis.
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Comment #6 posted by mai_bong_city on April 30, 2007 at 10:21:56 PT
i think
as a person who has a mental illness, i've found that cannabis is important in maintaining my balance. mood stabilization - i mean, when i have it i don't have the surge of mania, and when depressed, i don't feel suicidal.
that said, i have been working with neurologists and neuropsychologists and the endocannabinoid system exists in the brain of every creature excepting insects....just as other neurotransmission systems in the brain (serotonin) some imbalance in the natural system is what's in play here.
especially in paranoid-type reaction - it is often the person's already sufficient endocannabinoid levels that are now flooded beyond normal capacity - in someone with a deficiency in these neurochemicals, this is not often the case. i don't get paranoid, i get 'right'. also, the difference in indica and sativa and how they act on the body systems - indica more on the body first, brain second. sativa - brain first. my brain seems to need a certain amount of supplement for me to feel normal. my illness is immunosuppressive and neurological in nature - so for me, a sativa acts first on my brain to control the rest of my symptoms physically - the brain being the control center, of course. i do not get that proper effect when using an indica-dominant strain. my body gets the levels, but doesn't know what to do with it if my brain's not on-board.
i think it just has to do with using subjects whose own endocannabinoid levels are perfectly in balance and then giving them something of....excess.
if you could measure those levels, such as in my brain, pre-dosing (and did they use the complete cannabinoid chain found in the plant? no, just synthetic portions) i think you would find some sort of frontal cortex issue to begin with, that then becomes properly regulated when the right strain and potency is introduced.
just my thoughts.
i'd be dead or bat-shit nuts without it. 
i don't think i'm the only one.
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Comment #5 posted by rob on April 30, 2007 at 10:00:39 PT:
Yep, sometimes the ol' wacky weed makes yah crazy. I used to have panic attacks when I smoked pot, but back then I had them when I didn't too. Pot just triggered it. It was a stressful time in my life. I even go far as to say I should not have smoked then, but that was awhile ago. Every now and then I have a couple bowls in my vapo with n0 ill effects.And to tell you the truth, if I went into a hospital high as hell, I would probably still freak the hell out. Weed is a perceptual drug. Set and setting matter.
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Comment #4 posted by Taylor121 on April 30, 2007 at 09:45:33 PT
Check out the Reuters Article
It's much more balanced
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Comment #3 posted by dongenero on April 30, 2007 at 09:42:54 PT
Oh c'mon now........honestly
I would not deny that cannabis changes your perceptions to a mild extent. It can even cause a bit of paranoia depending on the situation and the strain of cannabis. I have to think that psychosis is way overstating any direct response to cannabis.psy·cho·sis (s-kss)
n. pl. psy·cho·ses (-sz)
A severe mental disorder, with or without organic damage, characterized by derangement of personality and loss of contact with reality and causing deterioration of normal social functioning.My guess is that there is a lot more psychosis in the US and British governments than there are in the cannabis using population. Lets see a study of citizens mental health resulting from the psychotic foreign policies of our respective governments. 
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Comment #2 posted by cannabliss on April 30, 2007 at 09:39:51 PT
Science "Reporting"
A common problem with such articles is they leave so many specifics unmentioned and then make blanket generalizations.What was the dose given to these people, over what time, what constitutes a schizophrenic symptom, etc. Maybe these people were too stoned...I'm not one to say smoking pot is just like having a glass of milk, but to say that half the people experienced schizophrenic symptoms strains credibility past the breaking point.In my extensive, reality-based experiments, I have seen hundreds of instances of pot smoking with no psychotic symptoms - unless relaxation, giddiness, and hunger are symptoms of psychosis.
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Comment #1 posted by OverwhelmSam on April 30, 2007 at 09:30:53 PT
So What
Alcohol causes people to become violent, cigarettes cause cancer, coffee causes anxiety, boxing causes brain damage. 
Cannabis consumers are affected in different ways, some get paranoid, but it's not paranoia if the fear is real.If you are standing on the edge of a 1,000 foot cliff, the paranoia is not imagined, the fear of falling is a real danger.
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