@SzAdmin posted a new topic, subject "New Study shows how Cannabis / Marijuana damages White Matter in Brain of people with First Episode Psychosis / schizophrenia". It read:

   The team explored the impact of cannabis potency in inducing psychosis. They used an MRI technique to look at the white matter of 99 people, 56 of which had reported a first psychotic episode. **They found that white matter damage was significantly greater among heavy users of high-potency cannabis compared to occasional or low-potency users.**
    
    Dr. Paola Dazzan, reader in neurobiology of psychosis from the Institute of Psychiatry, Psychology & Neuroscience (IoPPN) at King's College London, and senior researcher on the study, said in a statement: **“We found that frequent use of high potency cannabis significantly affects the structure of white matter fibres in the brain, whether you have psychosis or not. This reflects a sliding scale where the more cannabis you smoke and the higher the potency, the worse the damage will be.”**
    
    Source:
    
    IFLScience
    
    ### Study Reveals What Cannabis Does To Your Brain
    
    According to a new study, smoking high-potency skunk-like cannabis can significantly damage white matter, which is responsible for connecting different are

So @anon9798425 replied

    By high potency I assume they mean skunk, and that skunk use is what they have studied? And by damage I assume they mean reduction white matter volume?

Then @SzAdmin said

    anon9798425:
    
    > I assume they mean skunk, and that skunk use is what they have studied?
    
    I wouldn't assume anything - I think what they are saying is that high potency (i.e. high in THC) cannabis really hurts your brain - and yes, that means white matter reduction.
    
    “skunk” doesn't have a scientific definition - so I think they don't mean whatever that is. They didn't so much study the cannabis - as much as they studied the brains of people who developed psychosis and who reported that they had smoked cannabis.
    
    More details below:
    
    ncbi.nlm.nih.gov
    
    ####  Effect of high-potency cannabis on corpus callosum microstructure.
    
    S Rigucci, TR Marques, M Di Forti, H Taylor, F Dell'Acqua, V Mondelli, S Bonaccorso, A Simmons, AS David, P Girardi, CM Pariante, RM Murray and P Dazzan, _Psychological medicine_ , Mar 2016 
    
    The use of cannabis with higher Δ9-tetrahydrocannabinol content has been associated with greater risk, and earlier onset, of psychosis. However, the effect of cannabis potency on brain morphology has never been explored. Here, we investigated whether cannabis potency and pattern of use are associated with changes in corpus callosum (CC) microstructural organization, in patients with first-episode psychosis (FEP) and individuals without psychosis, cannabis users and non-users.The CC of 56 FEP (37 cannabis users) and 43 individuals without psychosis (22 cannabis users) was virtually dissected and segmented using diffusion tensor imaging tractography. The diffusion index of fractional anisotropy, mean diffusivity (MD), axial diffusivity (AD) and radial diffusivity was calculated for each segment.Across the whole sample, users of high-potency cannabis had higher total CC MD and higher total CC AD than both low-potency users and those who never used (p = 0.005 and p = 0.004, respectively). Daily users also had higher total CC MD and higher total CC AD than both occasional users and those who never used (p = 0.001 and p < 0.001, respectively). However, there was no effect of group (patient/individuals without psychosis) or group x potency interaction for either potency or frequency of use. The within-group analysis showed in fact that the effects of potency and frequency were similar in FEP users and in users without psychosis.Frequent use of high-potency cannabis is associated with disturbed callosal microstructural organization in individuals with and without psychosis. Since high-potency preparations are now replacing traditional herbal drugs in many European countries, raising awareness about the risks of high-potency cannabis is crucial. 
    
    and
    
    en.wikipedia.org
    
    ### White matter | Clinical significance
    
    Multiple sclerosis (MS) is one of the most common diseases which affect white matter. In MS lesions, the myelin shield around the axons has been destroyed by inflammation. Alcohol use disorders are associated with decrease in white matter volume. Animal studies suggest that alcohol may cause loss of white matter by damaging oligodendrocytes, the glial cell responsible for maintaining myelin. Changes in white matter known as amyloid plaques are associated with Alzheimer's disease and other neurode...
    
    and
    
    en.wikipedia.org
    
    ### Cannabis (drug) | 
    
    The price or street value of cannabis varies widely depending on geographic area and potency. In the United States, cannabis is overall the number four value crop, and is number one or two in many states including California, New York and Florida, averaging $3,000 per pound ($6,600/kg). Some believe it generates an estimated $36 billion market. Some have argued that this estimate is methodologically flawed, and makes unrealistic assumptions about the level of marijuana consumption. Other estimate...

To which @anon9798425 replied

    No need to link me Wikipedia pages, but thanks for the link to the actual study.

After which, @marctjester added

    watch this… pretty funny…

After which, @anon63589023 added

    Treebeard you live in the uk…? Where they call it skunk.
    
    We used to fiend for skunk…the problem's I'm an addict and hate aa and sobriety 
    
    That said I'm more of a drinker these days which is still bad too.

So @anon9798425 replied

    turningthepage:
    
    > Treebeard you live in the uk…? Where they call it skunk.
    
    No, thankfully I don't. Not sure if I have tried skunk but from what I've read I don't think so. On the other hand maybe it's the same here as in the UK. I don't know but the stuff I've been smoking is not the most potent stuff there is. Trying to quit and I'm almost there BTW.

Then @anon63589023 said

    It just means dank, piff, fire, chronic, etc… It's slang for “good weed” they use in the uk. I used to be a marijuana enthusiast so I know. Now I have periods of doing it every other night, then periods of once a week. It's not a mind expanding psychedelic experience like it used to be anymore. Hard to stop anything if you enjoy it
    
    When I got paranoid from weed I didn't smoke for over a year, then when I increased antipsychotics I stopped getting paranoid and started again

After which, @bridgecomet added

    **My Dad has BPD—he smoked for 30 years-it helped with his anxiety. Now, he has been in a deep depression and the weed is not working for him anymore. My sisters are jetting back and forth to NJ to stay with him until he gets through this. He is now on Lexipro.  
    I call what he smoked skunk-because that is what it smelled like. The stuff we used to smoke when I was a kid never smelled like that.  
    My ex used to smoke and stopped when he starting getting paranoid, or didn`t feel right anymore. He has MS now.**

Then @crimby said

    I never enjoyed the high of marijuana that much, though I smoked a fair amount of it just to be sociable. It makes me paranoid. It gives me dry mouth. It makes me think things I don't want to think. Judging from my personal experience, I can believe that marijuana damages the brain. I always felt fuzzy for a few days after smoking it. I think this effect does lessen with subsequent use. In some ways marijuana is less dangerous than alcohol, in that marijuana doesn't incapacitate like alcohol does. Alcohol incapacitates worse than any drug I know. I do love alcohol, God help me.

So @far_cry0 replied

    i heard a lot about this white matter…actually what is white matter,???  
    what is its functions and roles in human brains…???

After which, @anon40540444 added

    I haven't smoked weed since 2001. I got some laced with PCP, and I started tripping. BAD!! Never again. To hell with weed. It has no place in my life, and never played a big part in the first place. Sometimes I find it shocking how many schizophrenics will smoke weed anyway, usually knowing (but not caring) that it is harmful.


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