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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

#31

Post by punkbit »

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…

True! But someone who learns to play the guitar, or a language at 8 ~ 15 years old shows skills that are very difficult to master (if not impossible) when you are older. There's a lot of evidence of this if you talk with guitar teachers, someone who moved and start speaking a different language when adult, etc...

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

#32

Post by CuriouslyC »

kristiandupont wrote: post #17

Absolute pitch is something that supposedly can only be learned before the age of 6 but the drug Valproate seems to reopen this window. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3848041/

I suspect that valproate works by increasing BDNF levels. Exercise also increases BDNF levels, and a diet high in fermentable fiber has been linked to increases in BDNF as well, through increased short chain fatty acid production. It is worth mentioning that valproic acid is just a branched-chain short chain fatty acid, so it is likely that many of its effects are similar to those from short chain fatty acids derived via dietary fiber fermentation.

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

#33

Post by CuriouslyC »

divbit wrote: post #28
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'.

Nature is basically the most prestigious scientific journal, along side Science. Getting a pub in either of those journals is considered a huge win.

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

#34

Post by phaedrus »

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've had the opposite experience - once I learn something like a language, I never forget it. But people around me do, and I think it's as strange as forgetting your own name or who your family was. On the other hand, I'm mystified by how efficient "normal" people's memory for places and directions is. It takes me hours of studying a map and many repetitions of practice to learn a new route, and if I don't go a certain way (even to get to my own house or in the neighborhood I grew up in) it fades just like people describe losing language. So it's like those two capabilities are exchanged in my brain.

My best friend and I took 2-3 years of German in high school, and we'd talk to each other using the German we learned. We also knew two German exchange students. In academic meets (test taking competitions) I placed in German II and my friend placed in German I.

Unfortunately we had no one to speak German with after graduating high school. In all the time after high school, I only ran into one native German speaker, at some conference. I said something like, "Ja, Ich spreche ein bischen Deutsch..." and based on my accent he said, "Oh? You've been to Germany then." I shook my head, sadly no I've never been.

Years later I saw my friend again and spoke some German to him, and he didn't understand me. So I used German phrases I remembered had been his "favorites", and I was shocked he even forgot those too. It felt like I was one of the Lost Boys in the movie "Hook" trying to get Peter Banning to remember he was Pan.

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

#35

Post by gilbetron »

divbit wrote: post #28
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'.

Nature is ... kinda good:

http://www.scimagojr.com/journalrank.php

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

#36

Post by redka »

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…

Considering that as we age we lose some of our neurons - even if not _because_ of aging itself but for other reasons such as drugs or disease - there still could be an observable difference in both 'plasticity' of our brain and our capability to learn.

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

#37

Post by gaurav_v »

biofox wrote: post #26
bsder wrote: post #24

Earlier quoted context omitted.

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

Interesting paper. Do you work in the area? I'm working on proving that memories are in fact stored in genetic material, as was believed back in the 60s.

Drop me an email (gauravvman at gmail) if you're interested in this kind of stuff! Would like to know how you came across this paper.

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

#38

Post by NutriSugar »

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 think learning is more about losing neurons, not creating it. Or meatspace neural netowrks are less about changing weights and more about pruning connections.

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

#39

Post by your-nanny »

divbit wrote: post #28
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'.

Nature is a research journal. In fact it is one of the premier research journals. A publication in Nature can make a career.

Nature is not a specialist journal however. Most fields publish in it.

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

#40

Post by StavrosK »

punkbit wrote: post #31
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…

True! But someone who learns to play the guitar, or a language at 8 ~ 15 years old shows skills that are very difficult to master (if not impossible) when you are older. There's a lot of evidence of this if you talk with guitar teachers, someone who moved and start speaking a different language when adult, etc...

Can you point to any studies? I don't know if this is because our brains get less plastic, or because we just stop bothering when we get older.

I have personally noticed some drop in language acquisition skills, but I'm learning Spanish at 35 and I wouldn't say it's significantly harder than learning English at 12 (apart from the fact that English is everywhere around me all the time, but Spanish is very hard to come by).

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