July 25, 2011

Only human brains shrink with age.

"We are very weird animals... Among neuroscientists, the assumption has been that species are all the same, but this shows there is something really unusual about the late-life biology of the human species."

54 comments:

Meade said...

If people really worried that their brains were shrinking, they would give up booze, they would give up drinking.

Martin L. Shoemaker said...

I was under the impression -- and this could be seriously dated, and completely wrong -- that we have by most measures a disproportionately long life expectancy. So is it possible that other organisms experience the same shrinkage if we can simply keep them alive longer?

traditionalguy said...

Well that is one way to lose weight.

But let's not go all Phrenologist over this factoid.

I say that some people's heads were always to big to begin with. This shrinkage could only make them into better people.

chickelit said...

People with the largest brains suffer disproportionately.

Pinheads, like the meek, win out here.

traditionalguy said...

Meade...Give up booze? That is so wrong at so many levels.

My glass of red wine Rx is my favorite one.

That's right, medical booze. But the IRS guys are as jealous as you are.

shirley elizabeth said...

There's a US Administration on Aging?

Dustin said...

I think perhaps we are smart enough that we age much more than we otherwise would.

That's all.

ricpic said...

Actually a good thing. As you get older you have less and less to say about more and more. Very relaxing it is. Of course there are monstrous exemptions like Carol Herman.






wv: raciss - I kid you not. Well, the truth will out.

Kevin said...

The human body itself shrinks. We literally get shorter as we age.

AllenS said...

I dunno. Seems to me that when I drink, I know everything.

Carol_Herman said...

Yes, Kevin, we get shorter.

But as I explained to my doctor, out feet get bigger.

ricpic said...

...when I drink I know everything.

You do! You do! Then it fades.

NotWhoIUsedtoBe said...

Intelligence has a price. Otherwise it would have happened a long time ago.

Tim said...

...the population ages, brains shrink, Obama gets elected.

Well, that theory's been proved.

What next?

David said...

Humans were not designed for long life. Only recently has long life become an expectation. We are having a terrible time adjusting our institutions and thought patterns to large populations over the age of 60.

Personally I'm having a blast getting old. But I understand the urge to create the Death Panels. We oldsters are expensive and inconvenient. Expect more of this.

Anonymous said...

Another unusual feature of human aging is that when women lose the ability to reproduce they normally have decades of life remaining. Among most other mammal species the females remain capable of reproduction almost until the end of their life spans.

Peter

Jose_K said...

life expectancy among precolumbian natives. 19 y males. 16 y females.We swere not supposed to live more than that. Other animals live what they were evolved to but for those that live a little longer thanks to human care or the extintion of their enemies by man. So commenters here are right.
Beside that, brain is a energy drainer. When you have less energy and less ability to get food , a big brain will kill you

Jose_K said...

Neanderthals had a bigger brain than homo sapiens. they were unable to survive the Ice Era

Lem the artificially intelligent said...

"Only human brains shrink with age."

Althouse quietly campaigns for Supreme Ruth Bader Ginsburg's retirement ;)

Carol said...

Doctors used to give Xanax and Valium to alcoholics but those make your brain shrink too.

edutcher said...

Of course, if that could be reversed, all the oldsters could work forever and we wouldn't need Social security or Medicare.

So much for the budget.

shirley elizabeth said...

There's a US Administration on Aging?

If there isn't, there will be.

Jose_K said...

life expectancy among precolumbian natives. 19 y males. 16 y females. We swere not supposed to live more than that.

That's hunter-gatherer, though, so I have to offer a partial disagreement.

Agricultural man lived to about 40, when the body began to wear out, so maybe that's the real peak.

Luther said...

Our brains shrink as we age because we don't require the same neuronal space to ruminate. Life becomes clearer and simpler, and those parts of the brain previously needed to find our place in the world slowly fade to black. Conservation of energy, so to speak.

Or, in the spirit of AllenS, I've had a drink, perhaps two.

bagoh20 said...

So when I reach 105 my brain may be the size of a young female. Will I automatically become a feminist?

bagoh20 said...

Drinking expands the mind, but not so much as LSD. I bet none of those old brains studied were steady trippers.

bagoh20 said...

It's the part that thinks about sex that shrinks. Young people are very swollen in that area.

Bruce Hayden said...

Neanderthals had a bigger brain than homo sapiens. they were unable to survive the Ice Era.

Not sure if that is correct. One theory is that they couldn't survive Homo Sapiens. We (HS) lived much more densely than did they, and thus had numerical advantages. Also, we tended to communicate better, and possibly had a better brain.

In any case, it was long thought that they died out without a genetic trace. But last week or so, I saw an article that genetic research shows that non-Africans have Neanderthal DNA that Africans do not. Not much, but enough to show a limited amount of interbreeding when we came out of Africa.

There also was apparently an Asian relative who also died out, but they were assumed to have bred into the human sapiens sapiens population before petering out.

wv: luving - reminds me that I am flying to D.C. Thursday on SW, and need to get tickets to CO for a couple of weeks from now. That will put me over the top for A-List for 2012, but not on track for the next level up. We shall see. I would be happier if I had wrapped up the A-List travel by the first of this month.

Freeman Hunt said...

It just gets toned.

rhhardin said...

Conservatives don't need it all to argue with liberals.

Henry said...

Do human brains age with shrinks?

bagoh20 said...

My Neanderthal friends would be quite upset by this talk, but I just show 'em a card trick and they forget what they're mad about. Can't hold their liquor either, but great golfers - every one owns a natural swing.

Freeman Hunt said...

Donald in Mathmagic Land illustrates this phenomenon when the narrator sweeps Donald's brain clean of "false concepts" and "antiquated ideas."

Freeman Hunt said...

You start out with this amorphous, flabby, slothful brain, and then you train it until it becomes a taut, sinewy cheetah-brain.

This is what I plan to say when I'm old anyway.

Luther said...

"It's the part that thinks about sex that shrinks."

No, not yet anyway. Well, perhaps it shrank, but it is now more cerebrally concentrated. Or, maybe that's just wishful dreams. Dreams don't count, right.

flatie, I ain't going there, yet.

Luther said...

"Drinking expands the mind, but not so much as LSD."

True.

The Professor should do a drug thread some day. I'd like to see the shit that would come out of that woodwork, were everyone honest.

Bruce Hayden said...

It will be interesting to see how this plays out.

One of the things to keep in mind is that evolution is about trade offs. And, as a result of evolution, we have big brains and long lives. Both of these cost resources that could be used elsewhere. The other thing to keep in mind is that in terms of evolution, nothing that happens after fertility really matters. Or, not very much.

So, my thoughts are that this phenomenon is caused by using more resources earlier, since there would not be a genetic advantage to spending them later throughout our separate existence from our closest ape relatives.

Luther said...

"It just gets toned."

Excellent.

"you train it until it becomes a taut, sinewy cheetah-brain."

Careful, Freeman.

Unknown said...

So when I reach 105 my brain may be the size of a young female. Will I automatically become a feminist?

Either that or you will get an intricate abstract tattoo on your lower back.

gadfly said...

Since humans use their brains differently than other primates, it is not at all surprising that we age differently. At birth, human babies are helpless while chimpanzees and orangutans already possess basic motor skills.

In the end, however, the human brain wins out because "our ability to cooperate and share expertise has allowed us to build complex societies, collaborate and learn from each other at a high level, and use symbolic representation (writing, numerals, imagery) to communicate ideas."

Freeman Hunt said...

So what if our brains shrink and ape brains don't?

Ape civilization sucks.

Freeman Hunt said...

You know what humans have that other primates don't have?

A machine that can scan a head and make an image of the brain inside it.

Also, the mere understanding that there is an organ we call a brain or that there are organs at all.

MAKO said...

Here are some more "special" human beings for you - Trust me- Apes are MUCH more intelligent:

http://www.dreamindemon.com/2011/07/19/mother-robs-bank-with-toddler-for-drug-money/

http://www.dreamindemon.com/2011/07/21/woman-accused-of-forcing-child-to-live-in-closet/

http://www.dreamindemon.com/2011/07/21/drunk-mom-arrested-after-child-found-unresponsive-in-filthy-hot-home/

http://www.dreamindemon.com/2011/07/11/trial-begins-for-couple-charged-with-murder-after-snake-kills-toddler/

http://www.dreamindemon.com/2011/07/20/autistic-boy-molested-by-stranger-after-dad-advertises-him-on-craigslist/

Freeman Hunt said...

MAKO, you think chimps are nicer?

Anonymous said...

life expectancy among Precolumbian natives. 19 y males. 16 y females.We were not supposed to live more than that.

Very high infant and early childhood mortality greatly depressed those figures. A member of such a society who made it past early childhood could count on a life expectancy not drastically lower than people in developed countries today, say 50 to 60.

Peter

AlanH said...

"If people really worried that their brains were shrinking, they would give up booze, they would give up drinking."

I don't think so..moderate alcohol consumption is good for the brain.

http://www2.potsdam.edu/hansondj/HealthIssues/1103162109.html

Luther said...

Mako, I don't presume to speak for anyone here. Yet, I'll say, that the majority of us here are aware of deviancy from the norm.

Should I go out and find links to the cruelty, as you project of humans, of Silverback males.

mariner said...

Freeman Hunt,
This is what I plan to say when I'm old anyway.

Good plan.

Problem is, when it's time to say it, you won't remember it.

David said...

Maybe Obama is older than we think.

Chanie said...

Our brains need to shrink so that we can again not worry about our own death.

bagoh20 said...

A life flows determined like a river
to get to it's slow peaceful end.
It joins all the others if lucky, or if not shrinks and dries in the sand.
A man is not a river but an ape
in all that he tries to do.
He imagines himself to be god-like,
but mostly sits and flings poo.

Steven said...

I was under the impression -- and this could be seriously dated, and completely wrong -- that we have by most measures a disproportionately long life expectancy.

Yes, we do. Scaled for the impact of size on metabolic rate, pretty much all mammals live for the human body weight equivalent of about 25 years. Chimpanzees manage about double that. Humans, though, manage to treble that mammalian baseline. We should have lots of weird things happening with our body's aging process in order to pull off that stunt.

Now reading the article to see if this point has been made . . . ah.

"More broadly, though, humanity's unusual shrinking brain just may be the price our species pays for living so much longer than other primates, experts said."

So is it possible that other organisms experience the same shrinkage if we can simply keep them alive longer?

Maybe. Or maybe the same mechanism that allows us to live so long causes the brain shrinkage, too.

Or, putting on my wild speculation hat, age and brain shrinkage could have independently evolved for the same purpose.

The primary evolutionary utility of old tribe member to the "savanna ape" would have been as records of survival-important information learned long ago. Long life obviously improves this form of data storage because it means you have records that go back further.

Well, it might be that the brain atrophy—especially the reduction in the ability of the brain to form new memories—is a sacrifice of other capacities around the goal of preserving the brain's old memories, so that the old people can tell the kids what saved the tribe's life back sixty years ago. After all, there are plenty of younger tribespeople around to remember where the keys to the mammoth were left; a specialization in old memories might be of maximum benefit to the tribe.

[/wild speculation hat]

jamboree said...

I thought we WERE living in Chimp World.

I see about 80 percent of humans as having distinctly chimpish characteristics - only halfway out of the primordial ooze. It's not a racial thing, nor a class thing, a bit of an intelligence thing, it's just reality to me.

The left's constant comparison of Bush to a chimp made me laugh - their visceral irritation. That's how I feel all. the. time. Clinton was just a more chatty chimp yammering in the sun while he masturbated on a warm rock in his enclosure - but a chimp nevertheless.

I try and work on my attitude, but my opinion never really changes on that one - not really.

JAL said...

In the end, however, the human brain wins out because "our ability to cooperate and share expertise has allowed us to build complex societies, collaborate and learn from each other at a high level, and use symbolic representation (writing, numerals, imagery) to communicate ideas."

This.

This is why Obama is so pissed.

He wants the "cooperation" and "compromise" {<--- do it MY way}.

He thinks Boehner & Co. are devolving his utopia because *they* want to share their expertise -- like the need to balance the damned check book and cut up the cards and NOT go to Disneyworld this year or next or ride on the federal over draft financed bike paths or drive in federal over draft financed electic cars which need to be recharged every 50 miles from what would have to be federal over draft financed charging stations.

Boehner is acting like -- like an adult with a memory of what it is like to get caught with a huge credit card bill and no resources to pay it.

The xbox 360 doesn't work if the power is turned off, Barack.

Whose brain is smaller?

Maybe the cocaine did have lasting effect.

reader_iam said...

Has anyone yet posted the obvious smart-ass comeback?

"It's not the size, it's what you do with it."

; )

Kirk Parker said...

"Careful, Freeman".

She is being careful: note that should could have, but didn't, said "cougar brain".