
The Adult Brain Does Grow New Neurons After All, Study Says - Elof
https://www.scientificamerican.com/article/the-adult-brain-does-grow-new-neurons-after-all-study-says/
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KaiserPro
I have always had great difficulty in believing that in the human body,
_everything_ is regularly regenerated with the exception of neurons/ganglia.

The case in point is the sciatic nerve is massive, and prone to constant
stresses and strains, yet supposedly never regenerates.

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earenndil
I thought nerves aren't regenerated either?

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wickedsmile
Intact I read somewhere Cannabis consumption results in Neurogenesis. I am
trying to find something for citation but unable to find anything backing this
claim

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meko
Claims of legitimacy aside, The CBD portion of cannabis is supposed to have
this affect, not thc.

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heavenlyblue
Why CBD specifically? Where do you get that data?

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jjcc
There was a talk in DEFCON about different substances that could stimulate
neurogenisis and potential risks. The speaker mentioned the 1986 Nobel
laureate Rita Levi-Montalcini who found NGF gave herself some dosage of NGF.
The lady lived to 103 years old but the remarkable thing is that she is very
productive in very old age. Later I found those peptids are extremly expinsive
for normal people to consume

[https://www.youtube.com/watch?v=KPwjn17XQfs](https://www.youtube.com/watch?v=KPwjn17XQfs)

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BroEconomics
This? [https://www.amazon.com/Neuron-Growth-Factors-NGF-
capsules/dp...](https://www.amazon.com/Neuron-Growth-Factors-NGF-
capsules/dp/B001HBQ5A0)

Doesn't seem that expensive

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walamaking
No, she used the good stuff (eyedrops).

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rc_hadoken
Are you joking or are you serious? How are you going to respond to a serious
discussion with a flippant fact and not point us in the right direction? Care
to share where eye drops are obtained? I'm so curious

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jjcc
He is not joking. The speaker mentioned in the talk. Peptides are not stable
substance to be put into capsule. And the Bioavailability of NGF make it not
effective even by injection let alone put pills in mouth. Nasal spray and
sublingual are two other ways to absorb supplements but eye drop probably is
the most effective one.

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chisleu
It's important to note that this is talking about normal brain neurogenesis.
We have long known that external stimulus such as ECT, and chemicals such as
25i-nbome are neurogenic.

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pier25
25i-nbome? The psychedelic substance?

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blackflame7000
Yea I don't think synthetic LSD makes you smarter haha.

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chisleu
However, psilocybin (the active component of magic mushrooms) is also a strong
neurogenic compound, although not as effective as ECT. 25i-nbome is much
stronger than ECT, even in tiny doses which are far below the threshold for
any noticeable changes to perception.

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blackflame7000
I mean if that's what you call getting high now then go for it. You are
completely discounting any damaging effects and the associated disconnect with
reality.

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mdorazio
Two things to note from the article:

1) It seems to mostly be focused on neurogenesis in the hippocampus, not
necessarily elsewhere in the brain.

2) It seems the key item these researchers hit on to invalidate the previous
study was the method of preservation for brain tissue in deceased individuals,
not study of tissue in living humans. I think new studies in that latter area
in the future will put the matter to rest.

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superkuh
Neurogenesis has always been about the hippocampus in humans. It's been
lightly suggested it might happen in the olfactory bulb (as in other animals)
but not very seriously. When neuroscientists talk about human neurogenesis in
adulthood it is _always_ about the hippocampal formation and the dentate
gyrus.

For an up to date review/link-set of neurogenesis in humans as compared to
other mammals check out the summary write-up over at
[http://blogs.discovermagazine.com/neuroskeptic/2019/01/30/ne...](http://blogs.discovermagazine.com/neuroskeptic/2019/01/30/new-
look-neurogenesis-humans/) which makes the case that human neurogenesis isn't
found in adulthood because of relative lifespan differences.

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randomacct3847
I’m experimenting with Piracetam and Noopept while learning coding. With a
morning coffee I feel incredibly focused in ways I normally am not with
caffeine alone.

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amelius
I always wonder how people buy such chemicals, and know for sure that what
they receive is the exact ordered stuff with the given purity.

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bdamm
Indeed, there’s all kinds of reasons to want to verify received products. I’d
love to have a way to test supposedly organic foods for various pesticides. If
there was a book on basic chemistry needed for this kind of thing I think I’d
spend a season with it as a hobby.

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automatoney
So what age is considered "adult"? I've read other sources that say 26 or so,
but they base that on the fact that it's when the brain stops growing. Forgive
me if I missed something, but nowhere in the article do they define what adult
means in this context.

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dragonwriter
> Forgive me if I missed something, but nowhere in the article do they define
> what adult means in this context.

The two alternative conclusions presented are skepticism of any new neurons in
the target area _after toddlerhood_ and the conclusion that neuron development
_seems to be lifelong_ , though reduced in and with the progress of
Alzheimer's.

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pizza
Does anybody know of any diseases where there is excessive neurogenesis (and
whether that's a proliferation of ordinary or malfunctioning neurons)?

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lawrenceyan
Excessive neurogenesis from supplements almost always lead to things to like
glioblastomas, or brain cancer more simply put. You should always be wary of
anything related to increased growth or cell division.

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caraffle
Glioblastomas are what the name implies- tumors of glial cells. Neurons aren't
involved in proliferation.

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lawrenceyan
Glioblastomas are generally the only really common type of brain cancer
precisely because your neurons aren't proliferating in adulthood, which is
very much a good thing.

That's why I mentioned you should always be wary of anything that purports to
increase neurogenesis, as even if it does, that can lead to significantly
increased probabilities of cancer development. And brain cancer specifically,
is one of if not the most difficult types of cancer to treat, with extremely
limited survival outlooks.

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c3534l
I've been seeing articles with this title far longer than I ever heard
otherwise. Even if there are still people who think you can't regrow brain
cells after more than two decades of science to the contrary, it's probably
time we stopped saying things like "after all" as if neuroscientists just
recently figured it out.

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alanpetrel
I think this conclusion was fairly obvious, the key point is that realising
the neurons don't grow as quickly as they do in our early years.

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woliveirajr
> Llorens-Martin said she began carefully collecting and preserving brain
> samples in 2010, when she realized that many brains stored in brain banks
> were not adequately preserved for this kind of research.

I was always curious about it, and this piece shed some light over it: as
death is a process where all cells undergo chemical transformation, all you
add to stop the process and preserve some state also induces changes. So,
depending on how you preserve something, you will also lose information and
won't be able to further study something.

Interesting how we have a long road regarding preservation of bodies and how
much we still can improve about it.

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cheesymuffin
More on this in Aajonus Vonderplanitz's work -- We Want to Live and The Recipe
for Living Without Disease.

The best way to reconstitute neurons is to eat plenty of raw fish,
specifically saltwater fish.

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myth_drannon
Too much toxins from pollution, you are doing a lot of damage to your brain.

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cheesymuffin
You can soak up the toxins with raw no-salt-added cheese.

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modzu
"after all" is pretty misleading (edit: clickbaity?) for 2019. adult
neurogenesis has been known since 2009.

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mdorazio
FTA: "A growing body of research suggested they could, but then a Nature
paper[1] last year raised doubts."

[1]
[https://www.nature.com/articles/nature25975](https://www.nature.com/articles/nature25975)
"Human hippocampal neurogenesis drops sharply in children to undetectable
levels in adults"

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modzu
thanks for this, explains the context.

still, "a growing body of reseach" vs "a nature paper last year"?

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superkuh
It's not just that paper. There are many papers from many groups that have
failed to detect neurogenesis in the dentate gyrus of adult humans. Even
groups who's work is based on trying to find it have concluded it probably
doesn't happen. They did not want that result.

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abainbridge
Looks like Wikipedia has a summary of the history that might be useful to the
lay person (like me):
[https://en.wikipedia.org/wiki/Adult_neurogenesis#History](https://en.wikipedia.org/wiki/Adult_neurogenesis#History)

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fucking_tragedy
I had the impression that hippocampal neurogenesis in adults has been accepted
as fact for quite some time.

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Apocryphon
So does Alzheimer’s and dementia kick in when this process ends?

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JamesBarney
No it's more the case that Alzheimers and dementia are caused by other
processes which reduce or end this process. And a lot of the damage isn't
necessarily caused by reduce neurogenesis but by other factors.

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okonomiyaki3000
It does, eh? Hold my beer. No wait, I'm gonna need that.

