Scans Show How Cannabis Affects Brain

Scans Show How Cannabis Affects Brain
Posted by CN Staff on April 30, 2007 at 10:01:06 PT
By Reuters
Source: Reuters 
London -- Brain scans showing how cannabis affects brain function may help explain why heavy consumption of the drug triggers psychosis and schizophrenia in a small number of people, scientists said on Monday.Psychiatrists are increasingly concerned about the mental health impact of smoking large amounts of modern super-strength marijuana, or skunk, particularly among young people.
Until now, the mechanism by which cannabis works on the brain has been a mystery but modern scanning techniques mean experts can now detect its impact on brain activity.Professor Philip McGuire and Zerrin Atakan of London’s Institute of Psychiatry said their work using magnetic resonance imaging, or MRI, showed patients given the active cannabis compound tetrahydrocannabinol (THC) had reduced function in the inferior frontal cortex brain region.This area is associated with controlling inappropriate emotional and behavioral responses to situations.“What THC seems to be doing is switching off that part of the brain, and that was associated with how paranoid people became,” McGuire told reporters.Their research will be presented at a two-day International Cannabis and Mental Health Conference at the Institute of Psychiatry this week.Similar findings from other teams also highlight the link between THC dose and the risk of schizophrenia-like symptoms, conference organizer Professor Robin Murray said.“It’s no longer a contentious issue. The expert community, by and large, accepts that cannabis contributes to the onset of psychotic symptoms in general and the severe form of psychosis, schizophrenia,” he said.Double-Strength Joints One reason for the growing problem is thought to be the increasing strength of modern strains of cannabis, which are cultivated to produce the maximum amount of THC.In recent years, the average THC content of marijuana sold in Britain has doubled to 12 percent from around 6 percent, while in the Netherlands it is about 18 percent, Murray said.Most users of cannabis still do not have a problem with the drug but a minority, possibly because of genetic factors, are vulnerable to long-term damage from modern skunk -- which Murray says is to old-fashioned dope what whisky is to lager.The rise in THC content is linked with a decline in another active ingredient called cannabidiol (CBD), since the two products compete biochemically inside the cannabis plant.CBD, which reduces anxiety but does not produce the euphoric high of THC, may help offset some of the paranoid feelings.Markus Leweke of Cologne University said a clinical trial involving 42 patients showed CBD was as effective as the established medicine amisulpride, sold as Solian by Sanofi-Aventis, in treating patients with psychosis.“It seems there are good guys and bad guys within cannabis,” Leweke said.Note: Compound may trigger psychosis in some heavy users, scientists say.Newshawk: Taylor121 Source: Reuters (Wire)Published: April 30, 2007 Copyright: 2007 Reuters LimitedRelated Article:Study: Marijuana Damages Brain -- Cannabis Archives
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Comment #19 posted by FoM on April 30, 2007 at 21:11:47 PT
Thanks The GCW
It's posted now.
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Comment #18 posted by The GCW on April 30, 2007 at 20:44:43 PT
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 One of the active chemicals in cannabis inhibits psychotic symptoms in people with schizophrenia, according to a study which compared it with a leading anti-psychotic drug. Although the finding could lead to new treatments for schizophrenia, scientists think it may also explain why cases of cannabis-induced psychosis are apparently on the rise.
Most cannabis research focuses on tetrahydrocannabinol (THC), the active ingredient that produces the high. Recent studies have shown THC makes symptoms of schizophrenia worse and triggers the condition in a small proportion of users.But the new research shows that another chemical, cannabidiol (CBD), has the opposite effect. "One possibility is that there are good guys and bad guys within cannabis," said Markus Leweke, of the University of Cologne. He and his team compared the effects of CBD and a leading anti-psychotic drug, Amisulpride, on 42 patients with schizophrenia. After four weeks the symptoms of both groups had improved, but those treated with CBD suffered fewer side-effects.
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Comment #17 posted by mayan on April 30, 2007 at 18:04:47 PT
Ministry of Truth
After 9/11 and 7/7, I don't put much stock in what the tools of the U.S. and British establishments say. Here's a new piece which kind of puts their true interests in perspective...Heroin is "Good for Your Health": Occupation Forces support Afghan Narcotics Trade - Multibillion dollar earnings for organized crime and Western financial Institutions:
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Comment #16 posted by FoM on April 30, 2007 at 17:02:58 PT
I am feeling better now that Spring is here. The news down here is hard to take. I don't mean news about Cannabis but news in general. We gotta keep on keepin' on as long as we are able. Take good care of yourself. 
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Comment #15 posted by Marc Paquette on April 30, 2007 at 16:50:03 PT:
Well high! :)
Hi FoM - how are you my dear friend? :)Thanks for the good words sweetie - hang in there too, as your'e doing a great job as well! :)Marc
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Comment #14 posted by FoM on April 30, 2007 at 16:18:05 PT
I just wanted to say hi! Keep up the good work you are doing.
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Comment #13 posted by FoM on April 30, 2007 at 16:12:16 PT
Senate Considers Bill To Overhaul FDA
April 30, 2007Excerpt: Other amendments under contemplation include bids to further clamp down on conflicts of interest among FDA‘s expert advisers, guarantee agency scientists the right to publish their work without interference and subject medical marijuana to the same standards and penalties as any other drug sold to patients. Complete Article:
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Comment #12 posted by Marc Paquette on April 30, 2007 at 16:07:47 PT:
Making a storm in a glass of water!
Dear Friends;They say that cannabis only affects "a small number of people". How small? - 1% or 2%? LOL I bet that much more people are affected by using, acetaminophen, nasal sprays and any "legal" pharmaceutical narcotics! And how many deaths due to "legal" tobacco and alcohol? What are these prohibitionists trying to pull on us? Cannabis may affect a very small percentage of young people who are pre-disposed or already suffer from schizophrenia, but the dangers are so small, that it doesn't warrant or justify any reason for medias to amplify the situation of a non-toxic medicinal herb, while ignoring the majority of those who suffer from schizophrenia because of "legal" addictive and toxic alcohol, and "legal" addictive and toxic pharmaceutical narcotics and also their "legal" pharmaceutical antidepressants which in many cases, the use worstens the psychological state of some people and they fall into deeper depression, mutilation(s), suicide, or kill a loved one or someone else! Cannabis doesn't do this, and it doesn't kill anyone!! There may 2 important facts envolved in this matter.1) Visits to psychiatrists are decreasing due to too many patients using cannabis only to treat their chronic anxiety and depression - and psychiatrists feel that their purpose and jobs are threatened.2) Pharmaceutical companies are displeased and worried to see the sales of their antidepressants go way down!What other "sane" explanation would explain "why" mental health associations, their psychiatrists and pill suppliers use medias to misinform the puclic by boosting a minor problem affecting a tiny percentage of people?Marc
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Comment #11 posted by Sam Adams on April 30, 2007 at 13:53:35 PT
Studies & scientists
All I can think about when I read these is that it's YOUR life they're talking about! These aren't just harmless geeky guys off in some lab.  Their "results" will be used by your medical masters to decide which herbs & medicines you get to use, and which you cannot use or can only use as a criminal in our "modern" society.Once your health fails, you lose your freedom and enter a world where other people have total power over your life.
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Comment #10 posted by ekim on April 30, 2007 at 13:40:14 PT
New Truth Verification Technology
No Lie MRI, Inc. provides unbiased methods for the detection of deception and other information stored in the brain.
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Comment #9 posted by dongenero on April 30, 2007 at 13:12:40 PT
AP, Reuters....funny isn't it? these two friggin negative articles pop up all over AP and Reuters.The article last week about cannabis inhibiting lung cancer?....never showed up on AP or Reuters. Stopping lung cancer? Don't print doesn't fit the agenda! What a farce our media is anymore. Eschew the mainstream media. Seek out the truth from other sources. You have to be diligent to glean the truth from the various internet sources but, obviously the mainstream media is not serving us a good measure of the truth.
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Comment #8 posted by Richard Zuckerman on April 30, 2007 at 11:34:39 PT:
According to the movie entitled "The Corporation", corporations would be considered "psychopathic" under the DSM IV Revised. We are in much more danger from these "psychopathic" corporations than the few heavy "Marijuana" users. Nevertheless, there is no lethal dose from "Marijuana", despite the temporary adverse effects in a relatively few heavy users.Today, I was at Rutgers University, New Brunswick, New Jersey, campus, giving out the posters for this coming Saturday's Global Marijuana March, Some of these people seemed surprised that recently appointed Congressional Health Committee Chairman, Frank Pallone, Jr., who has a branch office in New Brunswick, N.J., now supports Med Pot! I asked them to contact Congressman Pallone for support of Med Pot. I have already called for support of the Hinchey-Rohrbacher Bill to cut off funding the DEA and to oppose S. 372, "Intelligence Authorization Act", which funds the U.S. intelligence agencies!!!!!
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Comment #7 posted by rafael on April 30, 2007 at 11:18:32 PT
comment #2
Yes, that is true. Some people can really freak out (have anxiety attacks) smoking the more sativa dominant strains. As far as I know, the more indica dominant strains don´t cause this effect.But that´s just with some people, mainly inexperienced smokers.p.s. It seems the reefer madness that´s going around UK nowadays is starting to appear on the US media.
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Comment #6 posted by museman on April 30, 2007 at 11:15:07 PT
Well, 'marijuana' may make one paranoid, but cannabis doesn't. ;}I am familiar with the effect. Here's something that I discovered;Cannabis takes on vibrational attributes of it's grower. If the herb is grown lovingly, and with good intention, then the 'high' will reflect that. If it is grown under the influence of fear and paranoia (not easy to avoid in growing a crop these days) then those influences are passed on to the end result. That's why people who grow their own for personal use and not sales or distribution tend to find their comfortable strains, and stay with it. I have smoked 'fear weed' but no one has ever gotten paranoid from smoking mine. And it's not a matter of potency.
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Comment #5 posted by Taylor121 on April 30, 2007 at 10:47:49 PT
Well, I'm not saying that marijuana makes specifically you paranoid, but it does for some people. 
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Comment #4 posted by museman on April 30, 2007 at 10:41:18 PT
"All this study said is marijuana makes you paranoid, something we have all known for a long long time."Cops (used to) make me paranoid, cannabis makes me free. These days, the cops just make me disgusted, and cannabis still helps to make me free.Paranoia is a side effect of society, not of cannabis.
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Comment #3 posted by freewillks on April 30, 2007 at 10:23:27 PT
I picked up on the same thing about " Most users of cannabis still do not have a problem with the drug" I also buy into the THC/CBD Ratio.Personaly I wiish we could walk into the five and dime and buy a pack that would state what the percentage is (THC/CBD)I bet most people would opt for the higher CBD. CBD acts like a non addictive Xanax.
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Comment #2 posted by rob on April 30, 2007 at 10:19:08 PT
CBD Treats psychosis?
I wasn't aware CBD was effective for treating psychosis.That implies that strains of Indica with there higher level of CBD should cause less "Freak out".Have you guys found this to be true? any thoughts?
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Comment #1 posted by Taylor121 on April 30, 2007 at 10:08:27 PT
Nothing really new
I don't really find that this study showed anything too new. We already knew that in a lot of people, marijuana causes some paranoia. What is honest about this article compared to the AP article is that it acknowledges, " Most users of cannabis still do not have a problem with the drug"The people that should worry are young teens and people that have a history of mental illness in their family. Cannabis could "bring out" their illness in those cases.However, cannabis use for healthy adults does not cause any long-term problems. All this study said is marijuana makes you paranoid, something we have all known for a long long time.
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