

Even Recreational Marijuana May Be Linked To Brain Changes - ytNumbers
http://www.forbes.com/sites/alicegwalton/2014/04/15/even-recreational-marijuana-may-be-linked-to-brain-changes/

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rainmaking
This is not that surprising; one would expect the brain to adapt after
exposure to a substance that affects its chemistry.

It is also completely meaningless, as there is no comparison done to measure
brain change in response to alcohol, nicotine, sugar, caffeine or even
different diets.

Finally, the article implies the brain change is harmful with no explanation,
which puts it square into junk science land. Shame on the authors.

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uslic001
How is 11.2 joints a week use categorized as recreational use?

[http://jn.sfn.org/press/April-16-2014-Issue/zns01614005529.p...](http://jn.sfn.org/press/April-16-2014-Issue/zns01614005529.pdf)

Marijuana use control MJ user No. days/week 0 3.83 (2.36) N/A No. joints/week
0 11.2 (9.61) N/A No. joints/occasion 0 1.80 (0.77) N/A No. smoking
occasions/day 0 1.80 (0.70) N/A Age of onset (years) — 16.6 (2.13) N/A
Duration of use (years) — 6.21 (3.43) N/A

I would consider that to be more than recreational use.

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mylons
do they quantify the joint too in terms of weight?

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uslic001
No. They could be smoking giant Bob Marley joints.

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mikhailt
The problem is that pretty much anything we do differently from our ancestors
harms the brain while it is still growing. Using sugar casually probably harms
the brain just as much as smoking pot casually does.

Sitting all day harms the brain. Heck, living in certain parts of the country
can harm the brain.

I agree with limiting pot use until the age of 18 but that applies to
everything else that's unnatural as well, such as sugar and salt (assuming we
set a limit that's healthy based on ancestor's diet and no BS chemicals).

So many things changed in the last century that our bodies can't adapt quickly
to support our diet and lifestyle. It takes tens of thousands if not hundreds
of thousands of years for the body to adapt to the environment we're living in
and how we're using our bodies. That's why obesity is starting to become #1
problem for the whole world as we continue to go further into the information
age.

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rainmaking
Not sure if pot smoking is something we do different from our ancenstors...

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Im_Talking
Bullshit study. Sampling of 40 people means nothing. Also, it said that
certain parts of brain changed in terms of shape and density but did not
determine whether this is a bad or good thing. In addition, I would like to
know who funded the study.

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a_bonobo
Paper:
[http://jn.sfn.org/press/April-16-2014-Issue/zns01614005529.p...](http://jn.sfn.org/press/April-16-2014-Issue/zns01614005529.pdf)

The statistical treatment looks solid, good p-values and they even controlled
for multiple testing with an adjusted p-value cut-off (alpha) of p < 0.0125

Funding is a bit biased: This work was supported by the National Institute on
Drug Abuse (Grants 14118,026002,026104,and 027804 to H.C.B. and Grant 034093
to J.M.G.), the Office of National Drug Control Policy, Counterdrug Technology
Assessment Center (Grants DABK39-03-0098 and DABK39-03-C-0098), and the
National Institute of Neurological Disorders and Stroke, National Institutes
of Health (Grant 052368 to A.J.B.). H.C.B. was also supported by the Warren
Wright Adolescent Center at Northwestern Memorial Hospital and Northwestern
University, Chicago.J.M.G. was supported by a Harvard Medical School Norman E.
Zinberg Fellowship in Addiction Psychiatry Research

Figure 1 has the gist, interestingly, gray matter density slightly increased
with Marijuana usage. The changes weren't that extreme for the most part, but
statistically significant. The L accumbens has the largest F (Table 2),
indicating a larger difference in gray matter density, the other areas don't
look that extreme.

I guess no-one can really say what that means exactly - is it good, is it bad?
Everything you do seems to change the structure of your brain in some way
(like reading a novel [1]), so it's really hard to tell whether this is 'good'
or 'bad'.

P.S.: It's a bit annoying that Internet discussions about publications
nowadays immediately just scream 'sample size!' without looking at the stats
themselves.

[1]
[http://www.theatlantic.com/education/archive/2014/01/study-r...](http://www.theatlantic.com/education/archive/2014/01/study-
reading-a-novel-changes-your-brain/282952/)

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ASneakyFox
Any time stats are used as "evidence" then you know its bs. You can just keep
picking variables until you got a chart you want.

