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| -Short Attention Span Theater- |
| Cannabis may shrink brain, scientists report |
| 2008-06-05 |
| Smoking cannabis for long periods of time may shrink parts of the brain that govern memory, emotion and aggression, according to researchers in Australia. Scientists used magnetic resonance imaging to scan the brains of people who admitted to smoking more than five joints a day for at least 10 years and compared them with brain images taken from non-drug users. Those who smoked cannabis regularly had on average a 12% smaller hippocampus, the part of the brain which is thought to be involved with emotion and memory, and a 7% smaller amygdala, which plays a role in regulating fear and aggression. For the study, researchers imaged the brains of 15 cannabis smokers and 16 individuals who did not use the drug. The scientists, led by Murat Yücel at the University of Melbourne and colleagues at the University of Wollongong, said scans on larger numbers of people were needed to confirm the extent of the effect. "Although modest use may not lead to significant neurotoxic effects, these results suggest that heavy daily use might indeed be toxic to human brain tissue," the scientists report in the journal Archives of General Psychiatry. Cannabis users also fared worse in tests of verbal memory and were more likely to have low-level symptoms of psychotic disorders such as schizophrenia and mania. Last month, a team at New York University scanned the brains of a group of 17- to 30-year-olds who had smoked cannabis two to three times a week for at least a year. In that study, the brains of drug users looked no different from those who had never taken cannabis. In 2004, Cyril D'Souza, a professor of psychiatry at Yale University, reported that THC, the active ingredient in cannabis, caused fleeting schizophrenia-like symptoms in users, ranging from suspiciousness and delusions to poor memory and attention span. |
| Posted by:tipper |
| #23 What did the pot smoker's brains look like before they smoked? Sample sizes of 15 and 16 are fairly small. I wonder what the error rates are. Hey don't Bogart that joint! |
| Posted by: JohnQC 2008-06-05 18:41 |
| #22 Those who smoked cannabis regularly had on average a 12% smaller hippocampus Yeah, but you should see the size of my eohippus! |
| Posted by: SteveS 2008-06-05 16:05 |
| #21 Maybe that's the problem with pot. It leaves one insufficiently aggressive. |
| Posted by: Abdominal Snowman 2008-06-05 14:47 |
| #20 Those who smoked cannabis regularly had on average a 12% smaller hippocampus, the part of the brain which is thought to be involved with emotion and memory, and a 7% smaller amygdala, which plays a role in regulating fear and aggression. Marijuana smokers in my experience aren't aggressive. Alcohol is way more of a problem in this regard. |
| Posted by: gorb 2008-06-05 13:54 |
| #19 How do people who smoke that much cannabis remember ten minutes ago, let alone ten years? |
| Posted by: Rambler in California 2008-06-05 13:29 |
| #18 Personally, I don't know ANYONE who can smoke that much. Scooter, You've just been hanging out with the wrong crowd. |
| Posted by: Frozen Al 2008-06-05 12:02 |
| #17 > the brains of people who admitted to smoking more than five joints a day for at least 10 years Maybe people who LIE/BOAST have a smaller hippocampus and amygdala? |
| Posted by: Bright Pebbles 2008-06-05 12:01 |
| #16 people who admitted to smoking more than five joints a day for at least 10 years Jesus H. Christ!!!! |
| Posted by: bigjim-ky 2008-06-05 11:32 |
| #15 No problem...the expansion of your waistline owing to Double-Stuff Oreos, Cheeto's (be careful of a person displaying yellow nostrils, by the way!), etc... will balance the books..... |
| Posted by: Uncle Phester 2008-06-05 11:07 |
| #14 We believe in nothing, Lebowski. Nothing. And tomorrow we come back and we cut off your Johnson! |
| Posted by: Mad Eye 2008-06-05 10:57 |
| #13 Where's the more than appropo Big Lebowski picture to go w/this thread? ...yeah, well, that's just like your opinion, man. |
| Posted by: Broadhead6 2008-06-05 10:34 |
| #12 If I smoke 18,250 joints in 10 years, my brain might shrink. And you would vote for Obama. |
| Posted by: JFM 2008-06-05 09:48 |
| #11 Dr. Egon Spengler: We'd like to get a sample of your brain tissue. Louis: Okay. |
| Posted by: Anonymoose 2008-06-05 09:32 |
| #10 So basically , if im a chronic pot smoker , and suffer from severe sternutation , my poor brain is screwed .. |
| Posted by: Mad Eye 2008-06-05 09:32 |
| #9 If I smoke 18,250 joints in 10 years, my brain might shrink. Good to know. |
| Posted by: Goober Glearong2367 2008-06-05 09:25 |
| #8 Dontcha hate articles like this that are so long that by the time you get to the bottom, you forget what it's about? Uh.... me neither what? |
| Posted by: Frank G 2008-06-05 08:54 |
| #7 Remember kids, just say ... ooohh pretty colors! |
| Posted by: DarthVader 2008-06-05 08:28 |
| #6 Those who smoked cannabis regularly had on average a 12% smaller hippocampus "Duude! A smaller hippocampus would mean, like, not all the hippos would get into school 'cause there, like, wouldn't be room for 'em. Bummer!" |
| Posted by: Mike 2008-06-05 07:23 |
| #5 Woah, dude, like, pot like, you know, like shrinks the brain? You mean, you're, like, just figuring that out? |
| Posted by: Mike 2008-06-05 07:19 |
| #4 Is it possible that cannabis smokers have smaller brains to begin with? You have admirably understood why interpreting statistics is not a job for amateurs. |
| Posted by: JFM 2008-06-05 07:14 |
| #3 Not sure about that cannabis linked shrinking... Is it possible that cannabis smokers have smaller brains to begin with? |
| Posted by: Spike Uniter 2008-06-05 07:03 |
| #2 It might also be a) People with mental health problems smoke cannabis b) Smoking anything shrinks the brain. |
| Posted by: Bright Pebbles 2008-06-05 05:05 |
| #1 My brain was too big anyway... Just for the record, 5 jays a day is a hellava lot of weed! Personally, I don't know ANYONE who can smoke that much. |
| Posted by: Scooter McGruder 2008-06-05 04:54 |