Does brain size matter?

I was walking through with your example, hoping you'd have a pertinent insight... if you do, please, by all means, share!
the point i am trying to make is in answer to your question "is brain size at all important". the simple answer is no.
 
the point i am trying to make is in answer to your question "is brain size at all important". the simple answer is no.

But what about all this stuff? Is it all garbage?
http://en.wikipedia.org/wiki/Brain_s...d_intelligence

A related study has reported that the correlation between brain size (reported to have a heritability of 0.85) and g is 0.4, and that correlation is mediated entirely by genetic factors (Posthuma et al 2002).

http://lib.stat.cmu.edu/DASL/Stories...elligence.html
Here, the correlation was found among introductory psychology students. There is a correlation of .51.

http://www.futurepundit.com/archives/003188.html

Brain size matters for intellectual ability and bigger is better, McMaster University researchers have found.

http://www.ctv.ca/servlet/ArticleNew...23?hub=SciTech
Study in Toronto, Canada finds correlation of IQ and brain size in a sample of 100.

Bigger is better when it comes to brain matter, says a leading neuroscientist.


"What is very clear is that there is a correlation between brain size and intelligence, particularly verbal ability," said Witelson

There is absolutely zero convincing evidence that brain size does not play an important role in intelligence--at least among humans.
 
But what about all this stuff? Is it all garbage?

surface areas of various brains.
yes indeed, size matters.

Total surface area of the cerebral cortex (human) = 2,500 cm2
Total surface area of the cerebral cortex (lesser shrew) = 0.8 cm2
Total surface area of the cerebral cortex (rat) = 6 cm2
Total surface area of the cerebral cortex (cat) = 83 cm2
Total surface area of the cerebral cortex (African elephant) = 6,300 cm2
Total surface area of the cerebral cortex (Bottlenosed dolphin) = 3,745 cm2
Total surface area of the cerebral cortex (pilot whale) = 5,800 cm2
Total surface area of the cerebral cortex (false killer whale) = 7,400 cm2
http://faculty.washington.edu/chudler/compare2.html

you will notice humans aren't even in the top 50%.

apparently brain size doesn't mean a whole lot does it.
 
...I found it amazing, the sheer number of people who are ignorant about the importance of brain size. So I made a thread that deals with it and confronts the ignorance.
Good idea. I will get one up soon about the correlation of IQ with height. - We need to keep all these dumb short people out of our schools, so I will work on that thread first.

Both height and brain volume correlate more strongly with innate IQ at birth than skin color does. Thus, US and many others are discriminating on the obvious, but much less valid, basis of skin color. - Silly is it not? (When more important correlates like height could easily be used.)*

I am thinking of calling my new thread:

"Tax money is wasted educating short people."

What do you think? Other suggestions?
------------------------------------------------
*Not only is height a better indicator of IQ potential than skin color, it is almost impossible for a short person to cheat. All blacks with generalized vitiligo can pass for whites and some like Michael Jackson have other means.
No short person can add more than a few inches even with every expensive painful surgery and vitiligo of some form is found in about 3% of the population - does not hurt is not contagious. Anyway you look at it, discrimination against short people (already done to some extent) is much better basis for improving the race's IQ than discrimination based on skin color. After we get the "shorties in their place," we can make more progress with laws that prohibit them from marrying, or at least not with us "tallies." - There is plenty of precedent for this in many state's miscegenation laws.


:rolleyes:
 
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Yes, I read it. And omg, you're so right! This only proves that we don't even need the whole brain! Isn't it weird that we have brains with two hemispheres when it's so obvious when we only need one to function! Ah, mother nature. What a dumb bitch.
Again, you fail to comprehend the importance of the material.
Nature is not a "dumb bitch".
Please explain how you can possibly think a person with a slightly smaller brain cannot function well, if a person with a damaged brain can.

francois said:
Quote me saying that.
francois said - "Within a species, because brain structure is generally very consistent, I think brain size plays an important role in an organisms intelligence. "

Yes, the brain is GENERALLY consistent, and specifically, inconsistent. Humans are generally primates, and specifically something else.

Also, I would like to see who has come out and said in other threads "there is no correlation of brain size and intelligence," and "brain size has nothing to do with intelligence!" - the most strident claim I have seen , just happened here when Leo said brain size was unimportant, but I haven't said that.

I have said however that brain size cannot account for a lack of cognitive function, except in the most extreme cases where the brain is too small to contain the necessary building blocks a brain needs to create functionality.

re-athletes - what about surfing? basketball? obviously the biggest muscles don't make the best athlete. Your view of the brain's cognitive function is like a person who thinks weightlifting is the only sport that exists. There are many functions in sports - balance, strength, planning, endurance, spatial referencing, etc., and being extremely good at one function can override a deficit in another.
You don't even see that the brain functions overlap - the link I posted about men and women's brains shows that they must. Different types of material (grey and white matter) can even be used to perform the same function.

Your position on cognitive function is highly oversimplified.

Edit - very funny billy - how tall are you francois?
 
Based on the links posted throughout this thread, is it fair to make the following statement:

General intelligence is somewhat correllated to brain size within the average adult human population, but is by no means correllated on an individual level.

Generally true, or not?

As for brain function remapping, this works best in children whos brains are still developing. For adults with serious brain matter loss, the outlook is bleak.
 
leopold said:

Originally Posted by francois
But what about all this stuff? Is it all garbage?


Originally Posted by leopold99
surface areas of various brains.
yes indeed, size matters.

Total surface area of the cerebral cortex (human) = 2,500 cm2
Total surface area of the cerebral cortex (lesser shrew) = 0.8 cm2
Total surface area of the cerebral cortex (rat) = 6 cm2
Total surface area of the cerebral cortex (cat) = 83 cm2
Total surface area of the cerebral cortex (African elephant) = 6,300 cm2
Total surface area of the cerebral cortex (Bottlenosed dolphin) = 3,745 cm2
Total surface area of the cerebral cortex (pilot whale) = 5,800 cm2
Total surface area of the cerebral cortex (false killer whale) = 7,400 cm2
http://faculty.washington.edu/chudler/compare2.html

you will notice humans aren't even in the top 50%.

apparently brain size doesn't mean a whole lot does it.

You're comparing brain sizes of different animals, leopold1--different animals with different kinds of brains. Animals that are homo sapiens, however, all have very similar brains, so in that regard, brain organization isn't much of a factor. A "false killer whale" has a different type of brain than a homo sapien, wouldn't you agree?

Did you read any of those studies that talk about brain size and intelligence correlations?

Billy T:
billy t said:
Good idea. I will get one up soon about the correlation of IQ with height. - We need to keep all these dumb short people out of our schools, so I will work on that thread first.
First, thanks for the response. Yeah, that would be interesting to know--the correlation of IQ and height. But you seem to be making an assumption here when you say "We need to keep all these dumb short people out of our schools, so I will work on that thread first." The underlying assumption is that I want to discriminate against people who have small brains. That is unwarranted. This is a science forum. I am interested in this stuff. Is there something wrong with that? Let me know what I should or should not talk about or be interested in. I need guidance very much.
Both height and brain volume correlate more strongly with innate IQ at birth than skin color does. Thus, US and many others are discriminating on the obvious, but much less valid, basis of skin color. - Silly is it not? (When more important correlates like height could easily be used.)*
It is silly, I agree.

I am thinking of calling my new thread:

"Tax money is wasted educating short people."

What do you think? Other suggestions?

If you want, go for it. But if you think you're mocking me in some way, you should know it's a complete non-sequitur.

Cole man!
cole gray said:
Again, you fail to comprehend the importance of the material.
Nature is not a "dumb bitch".
I know she's not a dumb bitch. I was being fah-see-shus.

Please explain how you can possibly think a person with a slightly smaller brain cannot function well, if a person with a damaged brain can.

Uhm. Okay, this one is easy. I don't! I don't even know where you're getting this stuff. Non-sequiturs and strawmen. You have an infinite stock pile of them don't ya!


Also, I would like to see who has come out and said in other threads "there is no correlation of brain size and intelligence," and "brain size has nothing to do with intelligence!" - the most strident claim I have seen , just happened here when Leo said brain size was unimportant, but I haven't said that.
You want me to name names? Well, you've heard it from the one and only leopold1. There are others. I'm not naming names. They can come here and explain themselves.
I have said however that brain size cannot account for a lack of cognitive function, except in the most extreme cases where the brain is too small to contain the necessary building blocks a brain needs to create functionality.
If that's what you think, tell me why you think it's true. Like I said in the first post, I don't want this to be a discussion about opinions and "I believe this, because... einstein had a small brain and..." Back up what you say with studies or at least something incisive. So far, I've explained and bolstered my claim (that brain size is important) with studies and published research. I want you guys to do the same.


re-athletes - what about surfing? basketball? obviously the biggest muscles don't make the best athlete. Your view of the brain's cognitive function is like a person who thinks weightlifting is the only sport that exists. There are many functions in sports - balance, strength, planning, endurance, spatial referencing, etc., and being extremely good at one function can override a deficit in another.
You don't even see that the brain functions overlap - the link I posted about men and women's brains shows that they must. Different types of material (grey and white matter) can even be used to perform the same function.

Your position on cognitive function is highly oversimplified.

My claim is not "It's impossible to be intelligent if you have a small brain."
My claim is not "Brain size is the only factor that plays a role in a person or animal's intelligence."

All my claim states, is: "Brain size is important. Generally, in populations, smarter people have bigger brains." It's not controversial (at least to scientists), it's not unsubstantiated and it's not oversimplified. Since you think it's oversimplified, tell me why you think so.
 
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Did you read any of those studies that talk about brain size and intelligence correlations?
no, because i consider brain size almost irrelevant when discussing intelligence. i say almost because a really tiny brain would be considered retarded.

frankly i feel environment plays a greater role in intelligence than brain size thus:
According to Garlick, recent advances in neuroscience and cognitive science have suggested that different intellectual abilities require different neural connections in the brain and that the only mechanism that allows the brain to grow such connections would be an adaptation mechanism that responds to environmental input.
http://unisci.com/stories/20021/0117021.htm
 
[url said:
http://unisci.com/stories/20021/0117021.htm[/url]

Psychologist Dennis Garlick, Ph.D., of the University of Sydney in Australia, submits that the neural plasticity model of intelligence better explains how intelligence is developed. This model suggests that intelligence is created when neural connections in the brain are changed in response to environmental cues.

According to Garlick, recent advances in neuroscience and cognitive science have suggested that different intellectual abilities require different neural connections in the brain and that the only mechanism that allows the brain to grow such connections would be an adaptation mechanism that responds to environmental input.
That is what I was saying to francois for the last bunch of posts - given ALL the evidence, this makes the most sense.

There is absolutely no reason why a persons brain could not grow, in dimensions and structurally, according to the mental tasks set before them in childhood, as their brain matures - even tiny changes could have large results, IF they are changes which have a purpose. Untrained, unused brain mass isn't going to help anyone very much - hence the kuzweil/savant with stupid offspring example.

edit -
regarding
francois said:
All my claim states, is: "Brain size is important. Generally, in populations, smarter people have bigger brains." It's not controversial (at least to scientists), it's not unsubstantiated and it's not oversimplified. Since you think it's oversimplified, tell me why you think so.
People with good hand-eye coordination play sports well, but which percentage of the coordination is the cause and which is the result? You don't know. The percentage is inextractable. So, you can't prove the genetics specifically, but you CAN prove that practice is of utmost importance.
 
There is absolutely zero convincing evidence that brain size does not play an important role in intelligence--at least among humans.

Of course not true:

1. I saw a guy's brain's X-ray. He had a special condition with walnut-sized brain and he had normal intelligence.

2. We aren't using our brains very effectively. Only 10% of so its capacity is being used. As others pointed out in this thread, you can remove a huge part of the brain of a child and still can have a normal adult.
 
I've heard about this 10% capacity claim. But I also heard that it is in fact only 10% being used at any one time. That is, the whole of the brain is used, but not all at the same time?

Those stories about people fucntionaing normally with only half the brain are facsinating - is it some kind of in-built redundancy?
 
That is what I was saying to francois for the last bunch of posts - given ALL the evidence, this makes the most sense.

There is absolutely no reason why a persons brain could not grow, in dimensions and structurally, according to the mental tasks set before them in childhood, as their brain matures - even tiny changes could have large results, IF they are changes which have a purpose. Untrained, unused brain mass isn't going to help anyone very much - hence the kuzweil/savant with stupid offspring example.

Yes and no. Differences in brain structure can facilitate the growth of proper connections.

And as I have been showing ad nauseum in the other thread, most data regarding intelligence in the human brain is focussing more and more on the structure of the brain.

Hence what is the difference between a rodent and a human brain. It's mainly structural.

For instance a very rough structural difference between mouse and human brain:

The increased size of the cerebral cortex during evolution results primarily from a disproportionate expansion of its surface area (1-7), with the appearance of folds of the cortical surface (with hills corresponding to structures known as gyri and intervening valleys called sulci) providing a means to increase the total cortical area in a given skull volume. This expansion of the length and breadth of cerebral cortex is not accompanied by a comparable increase in cortical thickness; in fact, the 1000-fold increase in cortical surface area between human and mouse is only accompanied by an approximate twofold increase in cortical thickness (8).

Here is for instance a normal mouse brain and one of a transgenic mouse where beta-catenin is protected from normal degradation.

mousebrain.gif


It mimicks the increase in cortical surface.

Moreover the human brain has a 6 layers of neurons in its cortex while most animals have only 3.

Moreover, although the histology of the brain is basically the same in every human, the morphology isn't. Every brain is structurally different.

The biggest structural differences can of course be found between men and women.

Similarly you might have noticed that they genitalia are different too.

One could measure how far genitalia could shoot sperm and you find a striking correlation. Men shoot sperm much further with their genitalia than women.
 
On a related note:
http://news.bbc.co.uk/2/hi/health/6037836.stm

Regions of the brain may not communicate with each other as efficiently as they should in people with autism, research suggests.

in some parts of the cortex brain cells made too many connections, and in other parts not enough.

Lead researcher Dr Michael Murias, from the University of Washington, said: "Our findings indicate adults with autism show differences in coordinated neural activity, which implies poor internal communication between the parts of the brain."
The researchers found people with autism particularly showed abnormal patterns of brain cell connection in the temporal lobe, which deals with language.
 
There is absolutely no reason why a persons brain could not grow, in dimensions and structurally, according to the mental tasks set before them in childhood, as their brain matures - even tiny changes could have large results, IF they are changes which have a purpose. Untrained, unused brain mass isn't going to help anyone very much - hence the kuzweil/savant with stupid offspring example.

Cole... that was never my argument. It was never my argument that a person who is untrained and has a bigger brain would outperform a person who has a smaller brain, but is trained. I hate those kinds of analogies. They are so riddled with logical flaws. I'm not even going to indulge you.

I want people who disagree with my thesis to disprove that smarter people generally have larger brains. To do this, citing a few examples of freaks with small brains and high IQs is not going to be sufficient. Similarly, if I based my argument on only a few samples, I wouldn't expect anyone to take me seriously. If I mentioned a few people who had large brains and high IQs and used that as evidence to bolster my argument, well, that would be pretty lame and illogical.

But this general tendency is very well documented, as I have already demonstrated.
 
to give you the benefit of doubt i have checked your links.
all of them but one are broken and in the case of wiki the title doesn't exist.
the sole functioning link is:
http://www.futurepundit.com/archives/003188.html
from the above link is this:
It remains to be determined what the contribution of nature and nurture are to this cerebral size relationship with intelligence, Witelson said. She added that the results point to the need for responsibility in considering the likely future use of magnetic imaging (or MRIs) of brain structure as a measure of ability in student and workforce settings.

pay particular attention to the first sentence of the quote francois.
 
I want people who disagree with my thesis to disprove that smarter people generally have larger brains. To do this, citing a few examples of freaks with small brains and high IQs is not going to be sufficient. Similarly, if I based my argument on only a few samples, I wouldn't expect anyone to take me seriously. If I mentioned a few people who had large brains and high IQs and used that as evidence to bolster my argument, well, that would be pretty lame and illogical.

Can you show the brain size is not the RESULT of environmental and not genetic factors?
You find a correlation and assume it is a cause - I thought we already went over this.

Indisputable Fact - A correlation is not a cause.

Homework for you- design a study which would provide some evidence for your idea. Do that, and then maybe you will see why you haven't shown anything yet.
 
Yes and no. Differences in brain structure can facilitate the growth of proper connections.
I am not saying that putting a baby in a maze and feeding it cheese will make its brain develop like a mouse's or vice versa - rather that the small differences in structure can mean big differences in function, and that there are differences in structure throughout human populations.
 
The point of this thread is not whether or not brain size has anything to do with genetics. I'm sure it does. Similar to how other physical characteristics are determined by genetics.

The point is that smart people generally have larger brains.
 
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