Sex personality differences

[Darat]

Although our politics seems to indicate otherwise, genitalia are not brain.

But they are the only way (apart from chromosomes) to identify a female or male brain at least at the moment.

 

[W.D.Clinger]

The point is that you can't make a better than chance determination by looking at the brain alone.

In modern humans, brain size provides a (weak) clue. In males, the average brain size is about 15% greater than in females. Thus brain size alone, like height alone or weight alone, is enough of a clue to distinguish male from female with accuracy slightly better than pure chance.

It would probably be correct to say you can't do a whole lot better than chance by looking at the brain alone. It should be possible, by looking at the distribution of brain sizes in males and in females, to quantify just how much better than chance you can do by looking at brain size alone.

There are several other anatomical characteristics of the brain that are at least slightly correlated with the male/female distinction, so it might be possible to do even better by looking at those other anatomical characteristics in addition to brain size; how much that could improve the diagnostic would depend in part on the correlation of those other characteristics with brain size.

 

[Olmstead]

It isn't, but go on.

The point is that you can't make a better than chance determination by looking at the brain alone.

As Darat pointed out, the brain is plastic. It will change. When someone has completed their transition, and is functioning completely in society as their gender (which, science is discovering, is disconnected from chromosomes and genitalia), their brain will become more like those of people who function as the gender they were assigned at birth.

Have there actually been any double blind studies on this? Can you tell whether someone is a cis-man, cis-woman, transman, transwoman by simply looking at their brain (disregarding chromosomes)?

 

[Darat]

Have there actually been any double blind studies on this? Can you tell whether someone is a cis-man, cis-woman, transman, transwoman by simply looking at their brain (disregarding chromosomes)?

What has been done is to look at the structure of brains and the evidence has been there is nothing structurally unique that allows one to identify a female from a male brain. All you can say is - to use an easier example to describe - is that "on average" males are taller than females so the taller folk in any given group are more likely to be male. But of course any given group may have short men and tall women in it, or may be all female or male. You can't use the "on average" property to identify whether any specific brain is female or male.

 

[lomiller]

There seems to be a general agreement that there are men who are more masculine than other men and women who are more feminine than other women?

Do you think that these differences are entirely socially constructed?

from wikipedia

"Femininity (also called womanliness or girlishness) is a set of attributes, behaviors, and roles generally associated with women and girls. Although femininity is socially constructed,[1] research indicates that some behaviors considered feminine are biologically influenced"

"Masculinity (also called manhood or manliness) is a set of attributes, behaviors, and roles associated with men and boys. Although masculinity is largely thought to be socially constructed,[1] research indicates that some behaviors considered masculine are biologically influenced."




The concepts of femininity and masculinity are themselves primarily social constructs. If you have once society where harvesting plants is a mans role, and another where it's a women's role what does it say about someone who prefers the role of harvesting crops? Are they transgender in one society but not in the other? What gender would that same person be in a society where there is no preference for who does this particular work?

 

[Warp12]

What has been done is to look at the structure of brains and the evidence has been there is nothing structurally unique that allows one to identify a female from a male brain. All you can say is - to use an easier example to describe - is that "on average" males are taller than females so the taller folk in any given group are more likely to be male. But of course any given group may have short men and tall women in it, or may be all female or male. You can't use the "on average" property to identify whether any specific brain is female or male.

On average, males and females showed greater volume in different areas of the cortex, the outer brain layer that controls thinking and voluntary movements. Females had greater volume in the prefrontal cortex, orbitofrontal cortex, superior temporal cortex, lateral parietal cortex, and insula. Males, on average, had greater volume in the ventral temporal and occipital regions. Each of these regions is responsible for processing different types of information.

I think there is evidence that the brain develops differently, depending on male and female identities. I think most of the studies say this. So, what is the debate? That they come out pre-wired differently at birth? Are there any studies to suggest that? Have any such studies been done?

Sorry, I'm obviously not an expert, I am just asking.

 

[lomiller]

There are a group of people who are referred to as trans gender and there is a lot of debate currently about them, so I have not just arbitrarily selected that category.

Again though just because you can define a group doesn't mean you should. Binning continuous data is something you need to be cautious about at the best of time but when you have the freedom to construct those bins any way you want it gets a lot worse. If you construct a grouping to target a specific subset of data points you can almost never use that group for anything else.

So the first question is, - are there brain characteristics which are *usually* linked to a particular sex?

The second question is - if so are these brain characteristics always linked to a particular sex?

The answers appear to be, respectively, yes and no.

Lets say we manage to identity properties that are more common in the brains of 1 sex than another.

Now we look at a particular person and find they have:
property 1 that occurs in 60% of biological males and 30% of biological females
Property 2 that occurs in 40% of biological males and 70% of biological females



Does this person have a "male brain" of a "female brain"?

 

[lomiller]

What has been done is to look at the structure of brains and the evidence has been there is nothing structurally unique that allows one to identify a female from a male brain. All you can say is - to use an easier example to describe - is that "on average" males are taller than females so the taller folk in any given group are more likely to be male. But of course any given group may have short men and tall women in it, or may be all female or male. You can't use the "on average" property to identify whether any specific brain is female or male.

I get the feeling the OP is really means something more along the lines of "mind" rather than the physical brain. IIRC there is also some evidence for certain regions of the brain tending to be more active or larger in one sex vs the other (again on average) This probabaly isn't something you could determine from a physical examination of a brain though. I also seem to recall there being at least some evidence for differences in how each sex thinks, even after adjusting for social and cultural biases.

Again to my point, though, so what? If a trait is prevalent on 40% of biological males and 60% of biological females what does it tell you about the person as a whole? IMO it tells you absolute nothing about anything beyond the trait itself.

 

[theprestige]

It'll be fascinating if it turns out there really is a scientific basis for gender stereotypes. A woman can be competitive, prone to physical outbursts, and lacking empathy? No, that's just a man in a woman's body. A man can be kindly and soft-spoken, and content to be a stay at home parent while his partner is out grinding that cheddar? Nope, she's actually a woman in a man's body. She better not be wearing the pants in that relationship!

 

[Robin]

But they are the only way (apart from chromosomes) to identify a female or male brain at least at the moment.

But do you think that the behavioural and personality differences that exist on average between men and women are due to those things? That seems unlikely to me.

When people talk about "male brain" and "female brain" they are always talking about the hypothesised brain differences that underlie behavioral and personality differences observed between men and women.

So either there is some neural difference between men and women that underlies personality and behavioral differences and this is what we mean by "male brain" and "female brain", or else brains start more or less equal and the differences are due to culture and society in which case there is no such thing as a "male brain" and "female brain".

In neither case does the chromosomal difference you mention have any relevance.

 

[Robin]

Again though just because you can define a group doesn't mean you should.

Sure, just because you can define a group "children" and a group "adults" does not mean that you should.

But there are a number of good reasons that we should define those groups.

Binning continuous data is something you need to be cautious about at the best of time ...

And if you ever meet anyone who suggests that continuous data should be binned you should tell them that.

...but when you have the freedom to construct those bins any way you want it gets a lot worse. If you construct a grouping to target a specific subset of data points you can almost never use that group for anything else.

Not so, as in my earlier example. You can construct the groups "adult" and "child" in any way you want, for example you can make the cut-off at 16 years of age or 18 years of age or any other cut off you like.

But that does not mean that the categories "adult" and "child" are not meaningful or that they cannot have a usefulness in different situations.

Lets say we manage to identity properties that are more common in the brains of 1 sex than another.

Now we look at a particular person and find they have:
property 1 that occurs in 60% of biological males and 30% of biological females
Property 2 that occurs in 40% of biological males and 70% of biological females

Does this person have a "male brain" of a "female brain"?

I don't think that what I have suggested implies that you can make the distinction with only two properties, so I am surprised at the question.

What I am suggesting is that someone with most of the properties that are usually found in most male brains might be said to have a male brain and that someone with most of the properties usually found in most female brains might be said to have female brains.

I don't think I have ever suggested that gender is binary or that there isn't a spectrum.

 

[theprestige]

So either there is some neural difference between men and women that underlies personality and behavioral differences and this is what we mean by "male brain" and "female brain"

What who means? Not "we", since I don't use the terms. I think they tend to normalize sexist stereotypes.

As far as I can tell, the only people seriously using "male brain" and "female brain" have no idea what the actual science of brains is. They're purely rhetorical terms used to normalize their preconceived notions of transsexuality.

Before you read this article, did you use the terms, "male brain" and "female brain"? If so, what did you imagine they meant? What basis in reality did you assume they had?

I think there's a huge problem with trying to retcon meaning, based on new information, for terms which were coined before that information was known.

 

[Robin]

What who means? Not "we", since I don't use the terms. I think they tend to normalize sexist stereotypes.

OK, "when most people use these terms...."

It seems to me that if I were to reject some concept then I would still want to be clear about what I was rejecting.

As far as I can tell, the only people seriously using "male brain" and "female brain" have no idea what the actual science of brains is.

They're purely rhetorical terms used to normalize their preconceived notions of transsexuality.

People who suggest that the social differences between men and women might be partly due to heritable brain characteristics are by no means limited to trans activists.

Steve Pinker and Lawrence Summers, for example are not usually classed as trans activists. Neither is the author of the article I quoted in my OP.

Before you read this article, did you use the terms, "male brain" and "female brain"? If so, what did you imagine they meant? What basis in reality did you assume they had?

I use the terms with respect to ideas and theories that other people have and I have already gone into a good deal of detail with my suggestion of what they might mean.

I have already indicated that the question of whether these things have any reality is ultimately an empirical one.

But if you insist that they have no reality then fine, but people like Steve Pinker, Lawrence Summers and many others who are not trans activists appear to be disagreeing with you so don't suggest that this is something made up by trans activists.

I think there's a huge problem with trying to retcon meaning, based on new information, for terms which were coined before that information was known.

Not really, it is just the issue that science has always had, thus we talk of a direction of current flow which is the opposite of the direction in which the electrons are moving. Causes confusion sometimes and the need to be careful in terminology but it is hardly a showstopper.

In science we always start with an observation and then hypothesise mechanisms which are often not known beforehand.

 

[Robin]

As far as I can tell, the only people seriously using "male brain" and "female brain" have no idea what the actual science of brains is.

There is a book called "The Female Brain" written by Louann Brizendine and here is her qualifications from Wikipedia:

Brizendine's research concerns women's moods and hormones. She graduated in neurobiology from UC Berkeley, attended Yale School of Medicine, and completed a residency in psychiatry at Harvard Medical School. She is board-certified in psychiatry and neurology and is an endowed clinical professor. She joined the faculty of UCSF Medical Center at the Langley Porter Psychiatric Institute in 1988, and now holds the Lynne and Marc Benioff-endowed chair of psychiatry. At UCSF, Brizendine carries out clinical, teaching, writing, and research activities.

So whether she is right or wrong you could hardly says that the has no idea about that the actual science of brains is.

Also a book cited by another in the thread says that it shatters the myth of the female brain. If the author has really shattered this myth then she must have had some idea of what she meant by the term.

 

[Robin]

It'll be fascinating if it turns out there really is a scientific basis for gender stereotypes. A woman can be competitive, prone to physical outbursts, and lacking empathy? No, that's just a man in a woman's body. A man can be kindly and soft-spoken, and content to be a stay at home parent while his partner is out grinding that cheddar? Nope, she's actually a woman in a man's body. She better not be wearing the pants in that relationship!

I don't see how any of that follows.

It is like saying that if we find that women are, on average, shorter than men then we would have to start saying a tall woman is a man.

No, of course none of those things you say follow.

 

[Robin]

I get the feeling the OP is really means something more along the lines of "mind" rather than the physical brain.

I am rather astounded that you get the feeling that I mean the opposite to the things I have been explicitly saying.

If I am talking about differences that can show up on neuroimaging isn't that a big hint that I am talking about the physical brain???

 

[theprestige]

I don't see how any of that follows.

It is like saying that if we find that women are, on average, shorter than men then we would have to start saying a tall woman is a man.

No, of course none of those things you say follow.

Of course it follows. You're making a bio statistical argument for transsexuality. Brain chemistry or leg length, what's the difference?

 

[Robin]

from wikipedia

"Femininity (also called womanliness or girlishness) is a set of attributes, behaviors, and roles generally associated with women and girls. Although femininity is socially constructed,[1] research indicates that some behaviors considered feminine are biologically influenced"

"Masculinity (also called manhood or manliness) is a set of attributes, behaviors, and roles associated with men and boys. Although masculinity is largely thought to be socially constructed,[1] research indicates that some behaviors considered masculine are biologically influenced."




The concepts of femininity and masculinity are themselves primarily social constructs.

The question I asked was "Do you think that these differences are entirely socially constructed?" and this seems a rather roundabout way of saying, no, you do not think that these differences are entirely socially constructed.

Which means that my point still stands.

If you have once society where harvesting plants is a mans role, and another where it's a women's role what does it say about someone who prefers the role of harvesting crops? Are they transgender in one society but not in the other? What gender would that same person be in a society where there is no preference for who does this particular work?

This question is completely unrelated to anything I have said or implied. Lets stick to the question at hand.

Find someone who has suggested the thing you are saying and ask them the question.

If you insist on an answer then of course I do not think that being transgender depends upon some single characteristic. I think I have made this point before.

 

[Robin]

Of course it follows.

So you think that tall women are really men?

Or are you saying that there is no average difference between the heights of men and woment?

If you think neither of these things then your point does not follow.

You're making a bio statistical argument for transsexuality.

I am? News to me. Perhaps you have mixed me up with someone else.

 

[arthwollipot]

In modern humans, brain size provides a (weak) clue. In males, the average brain size is about 15% greater than in females. Thus brain size alone, like height alone or weight alone, is enough of a clue to distinguish male from female with accuracy slightly better than pure chance.

It would probably be correct to say you can't do a whole lot better than chance by looking at the brain alone. It should be possible, by looking at the distribution of brain sizes in males and in females, to quantify just how much better than chance you can do by looking at brain size alone.

There are several other anatomical characteristics of the brain that are at least slightly correlated with the male/female distinction, so it might be possible to do even better by looking at those other anatomical characteristics in addition to brain size; how much that could improve the diagnostic would depend in part on the correlation of those other characteristics with brain size.

The correlations are weak. Without additional information, you have no way of knowing whether the brain you're looking out is simply a particularly large woman's brain or a particularly small man's brain. The ranges overlap too much.