Scans "reveal brain damage from cannabis is like schizophrenia"

Skyline_GTR

Bluelight Crew
Joined
Aug 28, 2002
Messages
4,326
Location
UK
SCIENTISTS have shown for the first time that the damage to brains from smoking cannabis is the same as that in schizophrenia sufferers. Images taken using a new scanning technique provide evidence that cannabis disrupts the brain’s electrical signals in the same way as in schizophrenia.

The findings add to growing evidence the drug may be a significant cause of mental illness in adolescents and a possible trigger for schizophrenia in those who are genetically vulnerable.

Previous studies have examined patients’ behaviour and medical histories. This is the first time direct evidence of a link has been found inside the brain.

“What we saw should cause alarm because the type of damage in cannabis smokers’ brains was exactly the same as in those with schizophrenia and in exactly the same place in the brain,” said Dr Manzar Ashtari, associate professor of radiology at the Albert Einstein College of Medicine in New York. Her research was presented last week to the Radiological Society of North America in Chicago.

Ashtari added: “To me, this is proof of the damage cannabis can do and it is shown up graphically for the first time. All the research by psychiatrists so far has strongly suggested cannabis-smoking youngsters run a higher risk of developing psychotic behaviour. Now we have extremely strong evidence that shows what damage has been done.”

The new research will add to pressure on the government to change its policy on cannabis. Last year the drug was downgraded from class B to class C, which means the police no longer routinely arrest people caught with small amounts.

The Advisory Council on the Misuse of Drugs is shortly expected to tell Charles Clarke, the home secretary, that evidence of the harm caused by cannabis is not strong enough for this decision to be reconsidered.

Ashtari’s team used a new technique called diffusion tensor imaging to look into the brains of 15 cannabis smokers, who had all given up taking the drug a month before the study.

They had smoked an average of once a day for a year and were aged 15 to 18. Their brains were compared with those of schizophrenics and of healthy people.

The scans looked deep into the “white matter” — the material that connects brain cells. In patients with schizophrenia, electrical signals are no longer routed correctly.

Schizophrenia sufferers find they are unable to separate real from unreal experiences and may see hallucinations, hear voices, lose the ability to concentrate and become paranoid. Sufferers typically develop the illness between the ages of 17 and 30.

In both the schizophrenia patients and the cannabis users, damage was found to white matter in a bundle of nerves and other fibres in the left frontal lobe. This area is associated with language and hearing.

This part of the brain is still developing during adolescence, which means it is vulnerable to damage. “We were able to see in real time abnormal behaviour in this area which was not present in the brains of adolescents who did not have schizophrenia and had not smoked cannabis,” said Ashtari.

Robin Murray, a professor at the Institute of Psychiatry in London, said: “This does seem to be a landmark study, although we will need to see it repeated. For the first time, we are able to see the effects of cannabis smoking on the brain.”

----------------------------------------------------

Scans reveal brain damage from cannabis is like schizophrenia

The Sunday Times
Martyn Halle
11 December 2005


Link
 
So now the media is going to turn this into "smoking pot makes you schizophrenic."

This article mentions nothing of the symptoms that a cannabis smoker may share with an any-stage schizophrenic. They clearly don't know enough about either one to draw any conclusions, though they are implied, because "identical" damage according to the scientists has no reason to produce identical symptoms.
 
...or if it is permanent at moderate doses..

...or if the "damage" that it does is ALL of what schizophrenic does, or just a symptom of a larger structural problem.

(structure vs. activity)....
 
Also, it seems that the study only focused on adolescents from the age of 15-18. What about people who start smoking after their brain has already gone through the adolescent stage of development?
 
Oh yes, what about all of that?

Well, they did their (FIRST) study on this group, and simply stated what they saw on their monitors. It was kind of a shot in the dark, you know.

I have schizophrenia in my family, I've smoked way too much pot in those target years, and I know my brain doesn't function in the same way it used to--such that I have to think differently to get the same results I used to get normally.

Kind of a dumb article, but I'm glad it's out there with this information.
 
This doesnt come as a shock to me really. There are alot of studies done on schizophrenia-cannabis. The results dont always point the same way. It's common knowledge that there is a link between cannabis use and schizophrenia. Although it's hard to know if smoking cannabis is a result of psychotic symptoms or that smoking cannabis results in psychotic symptoms.

Im biased on the topic, because I went through a psychose myself and I smoked alot of cannabis in my early teens. I dont smoke anymore and that's for a reason. I went to a congres last saterday about psychoses to see some presentations on a few studies currently done here in Holland. Again it was mentioned that smoking cannabis can result in a psychose.
There was another presentation by M. van Velzen and her study looked a bit like this one. She too concluded that there is a difference with 'normal people' in the language area on the left side in people with schizophrenia. This side is thought to be involved with interpretation of language.

This particularly study seems a bit sketchy. However maybe it's really a new landmark. It's hard to judge because the original research paper isnt released.
I didnt searched for it either, Im a bit lazy. Must be the result of smoking a lot of weed in the past :)
 
The sample size was n15, they DID NOT prove that cannabis caused the damage, and people have been smoking massive amounts of pot for thousands of years. I'm fairly unconvinced by this article...
 
cannabis disrupts the brain’s electrical signals in the same way as in schizophrenia.
is it talking about shortly after cannabis being administered, a couple days after, or a couple months after (significant wash-out phase)? this article is just turning science into propaganda
 
im likin this relative arguement because I myself wasnt prepared to totally indulge on this weed rhetoric. I think it has a ring of truth, but not in all its entirety. Id like to see more in depth conducive experiments. Not as many discrepencies.
 
qwe said:
is it talking about shortly after cannabis being administered, a couple days after, or a couple months after (significant wash-out phase)? this article is just turning science into propaganda

The article states the scans were done 30 days after last use.
 
qwe said:
or a couple months after (significant wash-out phase)?

Immediately noticed that as well, 1 month just simply isn't enough for people that have been smoking cannabis daily for over a year. For the rest, I don't really know what to make of this, they leave too many stuff out and it just seems like another propoganda article.

Meanwhile, Bilz0r posted an interesting abstract of an article a while ago, stating that there IS a genetic pre-disposition that makes people vulnerable to get a psychosis under the influence of cannabis.
 
Am I interpreting this wrong?

This leaves so many questions unanswered.

Do you only find this "damage" in schizophrenics and pot smokers or are some brains naturally more or less this way?

If these changes are the same as schizophrenia, why do the vast majority of smokers show so few shizo like symptoms? Obviously there's a lot more to schizophrenia than what they are scanning for. It seems irresponsible to say it's the "same kind of damage" when we're certainly not seeing the same kind of symptoms. Is it a matter of extent or is the guy criminally oversimplifying something here?

It's already obvious that anyone with shizophrenic tendencies needs to stay away from psychedelics. It's also obvious that pot causes changes in the brain. Maybe they just finally found something to scan for that can tell you whether or not somebody's smoked weed, and this particular method of scanning shows you something similar to that seen in schizophrenics when scanned the same way.

That doesn't prove weed causes brain damage, it just means what weed does in the brain and what schizophrenia does are similar in this single regard. Since obviously full blow schizophrenia involves deeper changes in the brain, this particular thing they're looking at might not even be that important.....am I missing something?
 
The abstract of their presentation is here:

http://rsna2005.rsna.org/rsna2005/V2005/conference/event_display.cfm?em_id=4419258

The results, specifically:

"A two-way ANCOVA was performed with FA levels in the SMA as the dependent measure, patient grouping and cannabis status (+/-) as main effects and age as a covariate. The overall model was significant (p<0.001) with cannabis status (p<0.002) and age (p<0.003) as significant main effects. In patients, after controlling for gender and premorbid social deficits, cannabis use accounted for 20% of the variance in FA values of SMA. In patients, abnormalities of FA in the SMA region were significantly associated (r=0.55, p=0.008) with worse performance of working memory."

I'm the wrong person to ask about diffusion tensor imaging, but my understanding is that it somehow measures the motion of water to determine the orientation of fibers passing through a region. My questions are:

Why is there no main effect of patient status on SMA (supplementary motor area) FA, if that is the "type of damage seen in schizophrenia?"

How does one rigorously measure "premorbid social deficits?"

Why do SMA abnormalities only correlate with working memory in patients? Doesn't this imply that SMA abnormalities are NOT associated with working memory impairments in the cannabis users?

It's almost certainly true that smoking pot every day for a year will probably affect brain functioning 30 days after you stop, but it seems to me like the relevant thing is whether there is functional impairment. For example, the study below found that people who had smoked weed in the last 6-36 hours had increased activity in more brain regions than controls when performing a working memory task with really easy (3 second) delays. However, performance was not different between the groups. Why they would do a working memory study without using a range of delays, I'll never know, but it proves the general principle that imaging results aren't the same thing as behavioral results.

http://www.ncbi.nlm.nih.gov/entrez/...&dopt=Abstract&list_uids=15205869&query_hl=44
 
I smoked 10 grams high-grade cannabis per week for 18 months, and smoked around an average of 4-6 grams per week (casually, not stoned all day) for like a year before that.

No schizophrenia yet, and I'm 19, almost to the age where it normally occurs.

Let's wait and see (although I quit smoking since then).

Also, I quote the other dude... "It seems irresponsible to say it's the "same kind of damage" when we're certainly not seeing the same kind of symptoms."

If the damage is the same, and they don't all have schizo, then maybe schizo causes the damage, rather than vice-versa. Irresponsible science and sensationalism. I'll wait for some more reports to come out. Shit, it didn't even say how many cannabis users had it and how much they smoked. For all we know, from their reports, you can smoke 1g one time and 100% of people who do this will have it, or maybe you can smoke 2g per day for 2 years and 23% of the people will show it.
 
Skyline_GTR said:
Images taken using a new scanning technique provide evidence that cannabis disrupts the brain’s electrical signals in the same way as in schizophrenia.
they never actually say what this new scanning tech is. just like the pet scan bs with e. just more propaganda.


hopefully someone puts Dr Manzar Ashtari in his place
 
Damn. A whole ten-minute talk on a study performed on a handful of subjects?? That's certainly enough to convince me that the neural makeup of schizophrenics overlaps significantly with that of stoners! Except, you know, for the amazingly gigantic holes in the design and execution of this study, and the gross oversimplification of every brain system and psychiatric disorder involved...

- People with a 'predisposition' towards schizophrenia can be drawn into psychosis by a LOT of things. Simply growing over, a major life change, a buildup of little things, a totally random series of events or one moment where consciousness is lost - and *certainly* ANY KIND OF MIND-ALTERING CHEMICAL. DUH. Perform this same study on, say, schizophrenics and chronic X users, or opiate addicts, or tweakers - and I imagine we'd see the same result. We might even see the same result without the addition of any substances - schizophrenics vs. 'potential schizophrenics' with a history of depression and social isolation, or schizoprhenics vs. PTSD victims, anorexics, hyperactive kids. Whatever. It's the whole 'don't push me 'cause I'm close... to... the... edge!' syndrome - if you have schizophrenia in your genes (or in your brain, in your environment, in your *!@&$)^$% personal web of fate!), it's likely that ANY aggravating mental circumstance, which might not make permanent neurological changes in the brains of "normal" subjects, will hasten the onset of schizophrenia.

- Diffusion Tensor Imaging. White Matter. What is the connection to BEHAVIOR? What is the connection to one's PSYCHE? EMOTIONS? I certainly don't see it, beyond a *totally not* "causal" relationship between how brain tissue looks before and after whatever event is being studied. How does this relate to the psychiatric and perceptual complexities of a disease like schizophrenia, which can barely even be defined as one single disease to begin with? PLASTICITY HAPPENS, people. We are always changing the shapes of our brain parts, when we think, when we respond to events in our environment, when we use certain circuits and electrical/chemical sequences over and over and over again, or when we ignore other pathways and let them die off, forgotten. Just because you perceive some similarities between *the appearance of* schizophrenic-brains and another group of subjects doesn't mean those similarities alone are the entire basis for a correlation between overall brain *functioning* between the two groups. There's a lot more to brain, mind, and personality than structure alone - there are a million other variables to take into consideration when trying to define what shapes the behavior and brain function of any individual - try, perhaps, adding a few supporting points regarding environment, electricity, neurochemistry, immunology, the world the individual has lived in and adapted to, etc. etc. etc... and then you *might* have a 1/1000th of the interacting variables that come together to make every human being the way they are.

- Study design... why the 2X2 design (Schizophrenics, Stoner Schizophrenics x 'Normals,' Stoner 'Normals') Why not just simplify the entire equation and compare Stoners to Schizophrenics? I kind of feel like this weights the study unevenly...

- Relevance of the SMA to, um, anything? "Since the supplementary motor area (SMA) is consistently been observed as the area with ongoing development during adolescent we have primary focused on this region." Okay.... that has absolutely nothing to do with the neural substrates of schizoprhenia, psychosis, the effects of cannabis... it's just convenient because it's been studied before, and deemed by some to play a role in adolescent development. Know what else plays a role in the critical periods of social and emotional development? EVERYTHING. I would be a lot more convinced of this study's validity if they hadn't narrowed their focus this way - maybe they could have looked at other brain systems and areas that are more directly linked to the disease itself, or even just to brain parts that have more to do with emotions and cognition, rather than... motor functioning?


Longtime lurker... just waiting to unleash a tirade... good to meet you all :)
 
definitely an interesting article, and i definitely want to hear more about this when they know more. but until then i think its safe for me to smoke every once in a while. :) if i start to hear voices then maybe i will stop.
 
I think most people would stop if they started hearing voices^^

This article is lacking in a good amount of test subjects and explains the theory so lackluster/vaguely that it is not even believable.
 
a "landmark" study, finally some "proof" for the neurological dangers of cannabis...stuff like this really is not good.

In both the schizophrenia patients and the cannabis users, damage was found to white matter in a bundle of nerves and other fibres in the left frontal lobe. This area is associated with language and hearing.
Great detail there. I understand there were much more eloquent and detailed replies before this one, but simply how can they draw assumptions like in this study. Isn't it misleading to say that there was some disruption observed somewhere in the left frontal lobe and that a similarity between scans of the potheads w/ the schizophrenics implies equal brain damage or effects? They're obviously trying to emphasize that marijuana causes significant brain damage in more than just schizophrenic manifestations.
 
I've smoked pot for over ten years and it's true, I'm certainly schizophrenic.

No I'm not.

Yes I am.


No I'm not.

Yes I am. KILL thE baD cLOWN!
 
Top