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View Full Version : In the Human Brain, Size Really Isn’t Everything



Jean M
12-28-2013, 12:19 AM
Scientists have long suspected that our big brain and powerful mind are intimately connected. Starting about three million years ago, fossils of our ancient relatives record a huge increase in brain size. Once that cranial growth was underway, our forerunners started leaving behind signs of increasingly sophisticated minds, like stone tools and cave paintings.

But scientists have long struggled to understand how a simple increase in size could lead to the evolution of those faculties. Now, two Harvard neuroscientists, Randy L. Buckner and Fenna M. Krienen, have offered a powerful yet simple explanation.

In our smaller-brained ancestors, the researchers argue, neurons were tightly tethered in a relatively simple pattern of connections. When our ancestors’ brains expanded, those tethers ripped apart, enabling our neurons to form new circuits. Dr. Buckner and Dr. Krienen call their idea the tether hypothesis, and present it in a paper in the December issue of the journal Trends in Cognitive Sciences.
http://www.nytimes.com/2013/12/26/science/in-the-human-brain-size-really-isnt-everything.html

Paper: Randy L. Buckner and Fenna M. Krienen, The evolution of distributed association networks in the human brain, Trends in Cognitive Sciences, Volume 17, Issue 12, December 2013, Pages 648–665
http://www.sciencedirect.com/science/article/pii/S1364661313002210


Highlights

• The human brain is triple the size of ancestors that lived 3 million years ago.
• Widely distributed cortical association regions are disproportionately expanded in humans compared with other primates.
• The separate association regions are connected by multiple large-scale networks that mature late in development.
• Cortical expansion may have caused critical properties of association networks to evolve as a spandrel.
• Many cortical features may be consequences of expansion in the context of conserved developmental programs.

Ian B
12-28-2013, 12:38 AM
Obviously not. The female human brain is smaller that that of the male, but look how many women are leaders in their fields of science, business and the arts. As for me, I'm a married man and wouldn't dare say anything else. :)

nuadha
12-28-2013, 08:27 AM
Obviously not. The female human brain is smaller that that of the male, but look how many women are leaders in their fields of science, business and the arts. As for me, I'm a married man and wouldn't dare say anything else. :)

I hope you are just as willing to say that women aren't better parents or more gentle/moral than men.

You mighg be sarcastic but the marriege comment sounds a bit submissive. I've noticed that many of the guys who joke about being submissive really are afraid of conflict so they will accept that women are always equal to men except when women are better than men...

Jean M
12-28-2013, 09:49 AM
I had no idea that a post on brain structure would kick off gender issues. Brain size correlates with body size in mammals. Elephants have huge brains; they are needed to control all that body mass. Human females are on average smaller than males. That is all there is to it.

As for male-female differences in personality - yes there are some, but these are averages. There is so much overlap that it is always unwise to make assumptions based on gender. You only have to read newspapers regularly to know that some women are bad parents. I can vouch personally for men who are extremely good parents. Many girls prefer literature to science, but some are quite the opposite. Boys on average are slower to talk and less chatty than girls, but don't we all know a man who can talk the hind leg off a donkey. ;) Women may be less aggressive than men on average, but women's boxing is now an Olympic sport, whearas some men are so peaceable you'd be hard put to it to ruffle one of their feathers, let alone provoke an outburst of violence. There seem to be exceptions to any gender generality.

Nirvana
12-28-2013, 10:22 AM
Removed post... not to derail the topic.

MikeWhalen
12-28-2013, 07:51 PM
Ha!! with age comes wisdom eh buddy? :)

on a more serious note, I'm guessing that proportionally, the female brain is the same size as males, so its misleading to just weigh the two out
- sort of like my eyeball is probably larger than the average females as I am a large male and for it to fit properly with my face, it has to be bigger-but the size does not relate to function, and a woman's eye works just as well (or better, I have a minor case of y associated color blindness) as mine

Mike


Obviously not. The female human brain is smaller that that of the male, but look how many women are leaders in their fields of science, business and the arts. As for me, I'm a married man and wouldn't dare say anything else. :)

Ian B
12-28-2013, 11:53 PM
I hope you are just as willing to say that women aren't better parents or more gentle/moral than men.

You mighg be sarcastic but the marriege comment sounds a bit submissive. I've noticed that many of the guys who joke about being submissive really are afraid of conflict so they will accept that women are always equal to men except when women are better than men...

I wasn't intending to be sarcastic, the last comment was meant as a joke. I accept that in some fields, women certainly are better than men, but I won't be drawn into an argument about the relative gender attributes. It's a simple fact of life, some people excel where others fail, regardless of gender.

Jean M
12-29-2013, 01:49 PM
I have a minor case of y associated color blindness

I'm no expert on colour-blindness, but I have not heard of any that is Y-related. All I know about is X-related. Because the common mutation for red-green colour-blindness is on the X, more men are red-green colour-blind than women, because they do not have an additional X which gives then another chance to have a working copy of the gene. https://en.wikipedia.org/wiki/Color_blindness#Genetics

ilmari
12-30-2013, 12:26 AM
I'm no expert on colour-blindness, but I have not heard of any that is Y-related. All I know about is X-related. Because the common mutation for red-green colour-blindness is on the X, more men are red-green colour-blind than women, because they do not have an additional X which gives then another chance to have a working copy of the gene. https://en.wikipedia.org/wiki/Color_blindness#Genetics
Yeah, I think he meant that his Y gets in the way and makes his X work more, but for him as a Canadian male, that's probably a good thing.

MikeWhalen
12-31-2013, 06:54 AM
the danger of tossing a phrase around people who know their science...I only know what I was told long ago, that a much higher % of men have the type of red green color blindness than women...up to 10-15% of the male population was the stat I read...so I blamed it on some y-linked problem...re reading what you wrote, Jean, you mean I can blame my Mom for my color blindness, much like my male patterned baldness?
Ha! if she were alive she'd give me a dirty look and mutter about stupid scientists
:)

as for Ilmari....thhpppppttttt!

M



I'm no expert on colour-blindness, but I have not heard of any that is Y-related. All I know about is X-related. Because the common mutation for red-green colour-blindness is on the X, more men are red-green colour-blind than women, because they do not have an additional X which gives then another chance to have a working copy of the gene. https://en.wikipedia.org/wiki/Color_blindness#Genetics

Jean M
12-31-2013, 09:30 AM
Jean, you mean I can blame my Mom for my color blindness, much like my male patterned baldness?

Afraid so. The women pass it on and the men get lumbered.

MikeWhalen
12-31-2013, 03:46 PM
wimin!

Mike

Ian B
01-01-2014, 05:50 AM
wimin!

Mike

Perzackery!!!

nuadha
01-05-2014, 09:02 AM
I had no idea that a post on brain structure would kick off gender issues. Brain size correlates with body size in mammals. Elephants have huge brains; they are needed to control all that body mass. Human females are on average smaller than males. That is all there is to it.

As for male-female differences in personality - yes there are some, but these are averages. There is so much overlap that it is always unwise to make assumptions based on gender. You only have to read newspapers regularly to know that some women are bad parents. I can vouch personally for men who are extremely good parents. Many girls prefer literature to science, but some are quite the opposite. Boys on average are slower to talk and less chatty than girls, but don't we all know a man who can talk the hind leg off a donkey. ;) Women may be less aggressive than men on average, but women's boxing is now an Olympic sport, whearas some men are so peaceable you'd be hard put to it to ruffle one of their feathers, let alone provoke an outburst of violence. There seem to be exceptions to any gender generality.

I understand what you are saying but I was actually talking about the average propensity of men and women to be violent as roughly equal. Hundreds of domestic violence studies point towards about equal likelyhood for men and women to initiate violence towards their partner, and I don't just mean a slap on the face. This same result seems to hold accross very different cultures. its probably just a human thing...

http://www.csulb.edu/%7Emfiebert/assault.htm

of course men are more violent outside the home, usually towards other men, but men experience a very different environment from women given their upbringing and responsibilities. similarly mothers commit more violence and murder towards infants than fathers.

I wish I could remember who said it, but I rember a quote from some woman saying that women would be too vicious if we allowed them in war. This kind of reminds me of all the girl fights that end in one girl getting jumped by the other girl and her friend. its like gang violence without the gang... I bring this up not to argue that one gender is more malicious but put doubt in the idea that women are less prone to violence.

MikeWhalen
01-05-2014, 07:47 PM
Well, as someone who works directly with criminals in both an operational role now, and a high end treatment modality previously, I can tell you that real world stats tell us to be very careful with any study that denotes 'who did what' in domestic violence as being equivalent between the genders!

Both research and practical experience tell us overwhelmingly that power and control issues are at the root of domestic violence. and men are overwhelmingly the perpetrator...period...any research that tries to claim differently is BS

-do the women hit back...yes some do
-do some women start the conflict on any given day (to get the tension phase over with as its easier to take the beating then anticipate it)-some do
-are women sometimes the Domestic violence perpetrator-yes, sometimes
BUT
the vast majority of domestic violence cases, be it physical, psychological, sexual (or any combination of the 3 forms of abuse), have men as the true perpetrator, or in some cases, should I say predator

the most telling stat I can probably give is the bed ratio, which literally tells you how society actually deals with the violence....my institution has 5 beds reserved for females and 130 for males
-back in the 90's when it was a treatment only facility (substance abuse, anger management and domestic violence) there were 6 female treatment beds and 88 for men
-these numbers are roughly accurate for all Canadian prisons and jails and I'm pretty sure they are true for US, Britain and Australian facilities

Men perpetrate the violence, of any kind, at ridiculously higher rates than women
(...although as one small sad caveat, the last decade, women have been switching from 'economic or moral' crimes to more violent ones)

regards

Mike

Ian B
01-06-2014, 12:38 AM
Well, as someone who works directly with criminals in both an operational role now, and a high end treatment modality previously, I can tell you that real world stats tell us to be very careful with any study that denotes 'who did what' in domestic violence as being equivalent between the genders!

Both research and practical experience tell us overwhelmingly that power and control issues are at the root of domestic violence. and men are overwhelmingly the perpetrator...period...any research that tries to claim differently is BS

-do the women hit back...yes some do
-do some women start the conflict on any given day (to get the tension phase over with as its easier to take the beating then anticipate it)-some do
-are women sometimes the Domestic violence perpetrator-yes, sometimes
BUT
the vast majority of domestic violence cases, be it physical, psychological, sexual (or any combination of the 3 forms of abuse), have men as the true perpetrator, or in some cases, should I say predator

the most telling stat I can probably give is the bed ratio, which literally tells you how society actually deals with the violence....my institution has 5 beds reserved for females and 130 for males
-back in the 90's when it was a treatment only facility (substance abuse, anger management and domestic violence) there were 6 female treatment beds and 80 for men
-these numbers are roughly accurate for all Canadian prisons and jails and I'm pretty sure they are true for US, Britain and Australian facilities

Men perpetrate the violence, of any kind, at ridiculously higher rates than women
(...although as one small sad caveat, the last decade, women have been switching from 'economic or moral' crimes to more violent ones)

regards

Mike

Also having been involved in law enforcement for over thirty years, I agree with Mike as the situation is the same in Australia. It's a sad fact of life that some women will take the beatings as being part of life, and never complain. Men who assault women are beneath contempt imo.

Ezana
01-06-2014, 04:33 PM
Nuadha, the general differences between men and women can be discussed in another thread, but this one is specifically for the size of the brain as it relates to intelligence. If you want to discuss gender differences, feel free to make a new thread for that discussion.