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Brain tissue samples suggest we stop growing new neurons in our early teens

latimes.com

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Re: Brain tissue samples suggest we stop growing new neurons in our early teens

#21

Post by ramblerman »

I see this as a positive. I always lamented the idea that as we grew older we generated less and less neurons, and thus our learning capacity decreased (I thought).

But it seems even young university students are no longer generating neurons. Nor are the 30 year olds learning new languages or switching careers.

It seems neuron growth thus has nothing to do with 'plasticity' or our capability to learn.

* disclaimer: I know very little of neurology so please correct any false assumptions.

Re: Brain tissue samples suggest we stop growing new neurons in our early teens

#22

Post by sevenfive »

ramblerman wrote: post #21

I see this as a positive. I always lamented the idea that as we grew older we generated less and less neurons, and thus our learning capacity decreased (I thought). But it seems even young university students are no longer generating neurons. Nor are the 30 year olds learning new languages or switching careers. It seems neuron growth thus has nothing to do with 'plasticity' or our capability to learn. * disclaimer: I…

I mean, we already know the differences between 20- and 30- year olds from simple observation. So it's not really positive or negative.

Re: Brain tissue samples suggest we stop growing new neurons in our early teens

#23

Post by [deleted] »

sevenfive wrote: post #22
ramblerman wrote: post #21

I see this as a positive. I always lamented the idea that as we grew older we generated less and less neurons, and thus our learning capacity decreased (I thought). But it seems even young university students are no longer generating neurons. Nor are the 30 year olds learning new languages or switching careers. It seems neuron growth thus has nothing to do with 'plasticity' or our capability to learn. * disclaimer: I…

I mean, we already know the differences between 20- and 30- year olds from simple observation. So it's not really positive or negative.

[deleted]

Re: Brain tissue samples suggest we stop growing new neurons in our early teens

#24

Post by bsder »

jey wrote: post #7
bsder wrote: post #4

I thought they used isotope analysis from nuclear testing fallout to prove that the neurons in the brain are between 15-20 years old on average? How do they reconcile this? http://www.physicscentral.com/explore/action/nuclear-neurons...

A likely possibility: the molecules get replaced, but it's still the same cell.

DNA doesn't get replaced that I know of, and that's what they focused on.

The only way to get "new" DNA is for a cell to assemble a new strand during division.

Re: Brain tissue samples suggest we stop growing new neurons in our early teens

#25

Post by sergiosgc »

KozmoNau7 wrote: post #20
rorykoehler wrote: post #18

Earlier quoted context omitted.

I learned it as a teenager and lost it in my 20s. Like anything I learned it through practice and familiarity. Once I stopped working in music production I slowly lost my absolute pitch too. Similar to the way I used to be able to speak French but now can only string a few words together.

Similarly, I took German and French in school, and got quite good grades. However, I've not had much occasion to use either language since then. I did read some German news articles, so that part is sort of OK still. I've been with my (German) girlfriend for about a year now, and have visited her family in Germany a couple of times. It has really made me realize how much of my ability to put together a sentence in Ge…

I was having the same sort of difficulty with French. On vacation, I realized my ability to speak fluently had vanished over a decade of non-use of the language. I bought a few magazines, then a fiction book, and it's done wonders.

It's much more interesting to read about something that I'm interested in than it is to go through exercises. Since what you lose over time is mostly vocabulary, reading is an efficient way to re-grok a language. You just have to get over the initial bump, where you're reading really slow because you stop frequently on unknown words.

Re: Brain tissue samples suggest we stop growing new neurons in our early teens

#26

Post by biofox »

bsder wrote: post #24
jey wrote: post #7

Earlier quoted context omitted.

A likely possibility: the molecules get replaced, but it's still the same cell.

DNA doesn't get replaced that I know of, and that's what they focused on. The only way to get "new" DNA is for a cell to assemble a new strand during division.

DNA repair mechanisms can synthesise new segments in response to damage.

There was also a paper published last month claiming DNA synthesis following learning, but I'm sceptical:

https://www.ncbi.nlm.nih.gov/pubmed/29427086

Re: Brain tissue samples suggest we stop growing new neurons in our early teens

#27

Post by KozmoNau7 »

sergiosgc wrote: post #25
KozmoNau7 wrote: post #20

Earlier quoted context omitted.

Similarly, I took German and French in school, and got quite good grades. However, I've not had much occasion to use either language since then. I did read some German news articles, so that part is sort of OK still. I've been with my (German) girlfriend for about a year now, and have visited her family in Germany a couple of times. It has really made me realize how much of my ability to put together a sentence in Ge…

I was having the same sort of difficulty with French. On vacation, I realized my ability to speak fluently had vanished over a decade of non-use of the language. I bought a few magazines, then a fiction book, and it's done wonders. It's much more interesting to read about something that I'm interested in than it is to go through exercises. Since what you lose over time is mostly vocabulary, reading is an efficient wa…

My girlfriend has taken Danish classes for two years, and we try to speak as much Danish as possible, with me giving her feedback on grammar and word choices. In return she sends me news and other articles in German, where I try my very best to read and understand them fully, without resorting to Google translate. So far it's going pretty well, actually :-)

Re: Brain tissue samples suggest we stop growing new neurons in our early teens

#28

Post by divbit »

bsder wrote: post #4

I thought they used isotope analysis from nuclear testing fallout to prove that the neurons in the brain are between 15-20 years old on average? How do they reconcile this? http://www.physicscentral.com/explore/action/nuclear-neurons...

Afaik nature has good stuff, but it's not like a 'research journal' it's more popular stuff. A quote from the article: "There are only a handful of studies out there that have already attempted to look at this, and they came to wildly different conclusions." So, although I didn't look into this more deeply, it seems to me there is wide room to not take this popular article as 'full confirmation'.

Re: Brain tissue samples suggest we stop growing new neurons in our early teens

#29

Post by jmkni »

sevenfive wrote: post #22
ramblerman wrote: post #21

I see this as a positive. I always lamented the idea that as we grew older we generated less and less neurons, and thus our learning capacity decreased (I thought). But it seems even young university students are no longer generating neurons. Nor are the 30 year olds learning new languages or switching careers. It seems neuron growth thus has nothing to do with 'plasticity' or our capability to learn. * disclaimer: I…

I mean, we already know the differences between 20- and 30- year olds from simple observation. So it's not really positive or negative.

What would you say the differences are, based on your observations?

Re: Brain tissue samples suggest we stop growing new neurons in our early teens

#30

Post by shaki-dora »

ramblerman wrote: post #21

I see this as a positive. I always lamented the idea that as we grew older we generated less and less neurons, and thus our learning capacity decreased (I thought). But it seems even young university students are no longer generating neurons. Nor are the 30 year olds learning new languages or switching careers. It seems neuron growth thus has nothing to do with 'plasticity' or our capability to learn. * disclaimer: I…

The neurogenesis hypothesis was always more about mood/mental health rather than learning, I believe.
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