In that instance, sure I am. I concede and have conceded the point that yes, the vast majority of the causes of male vs. female phenomena can’t be pinned down fully on either heredity or environment. That doesn’t mean that there aren’t certain gender-related neurological characteristics that can be fully or near-fully attributable to the topography of ones twenty-third chromosome.
I didn’t mean that you were literally suggesting the blanket theory, that was just some colorful (pun unintended) hyperbole on my part. However, why can’t one arrive at a reasonable scientific certainty that certain characteristics of brain functionality are fully attributable, or at least 99.99% attributable, to ones sex?
**
I could assemble a sample pool based on that methodology, but I’d be a poor scientist and researcher if I did. Perhaps ones bias can never be completely eliminated and as a result no experiment can ever be completely objective, but a good experiment would build in tolerance room for such error. If I adhered to a good experimental protocol and took care to assemble valid samples (as I’m sure many researchers have done already), and if the data thereby arrived at indicated that one could reasonably exclude every factor but the sex one is born with to explain certain gender differences, why can’t I conclude that the answer to the OP is “yes, there are indeed significant structural differences that in some cases are the sole cause of differing thought processes?”
See, the problem is that I am NOT so sure. I’m at work and searching for cites is not a possibility right now, so bear with me as I use my own experience to justify my opinion.
The problem with research in this area is that it IS a rather political question. And unfortunately, the bulk of the research done to date tends to lean toward producing an “excuse” for differential treatment.
For example, a researcher might look at the fact that there are more female secretaries than male and thus, do a research study to determine the reasons for this fact. The researcher then comes up with “conclusive proof” that women are more manually dextrous, based on brain structure, and therefore make better secretaries. (This is a real-life example and I promise to look up a cite for it as soon as possible).
Notice that the researcher in the example above didn’t bother to make note of the fact that there are more famous/successful male pianists than female, even though some of the same manual dexterity issues should cause the reverse to be true. What he’s done is simply provide an excuse for keeping women in secretarial jobs and men into more lucrative positions. Similar “research studies” have been done to determine why men can’t do housework, why they are poor listeners, why they’re prone to being unfaithful. These excuses ought to be just as insulting to men as they are to women.
I don’t think serious physicians or other researchers have any real interest in doing studies on whether or not our differences are brain-structure based, because they have the same opinion it seems you and I do: Men and women may be biologically different, but deserve a level playing field anyway. Therefore the REASONS they are different really don’t matter any more than the reasons individual people differ from one another.
In other words, these studies tend to be done by conservatives and anti-feminists, determined to prove their point. They are not, generally, taken up by the academic community.
My first reaction to this is “You can’t prove something that isn’t true.”
But the obvious reason why this can’t be proven is that it can’t be tested. It would be necessary to raise a decent sized group of male and female infants to adulthood in an identical fashion, with no exposure to any social or cultural ideas about gender roles, and then examine their brains. I am sure you can see the difficulties with conducting such an experiment. Yet in the absence of such research, it is impossible to determine what brain differences are purely biological.
The ironic thing is, Sexy, is that the point you’re arguing is very similar to a point that I’m arguing in this thread. However, I still think I can reconcile my two respective positions because I’m asserting in one case that the very premise of a question about a broad characterization is flawed, while in the other case I’m arguing that specific narrow conclusions may be drawn without resorting to blanket suppositions.
The meaning I was trying to convey wasn’t “Why shouldn’t one draw this conlusion?” I literally meant “Why would one be unable to draw such a conclusion if one conducted a scientifically valid experiment and then properly interpreted the data derived thereto?”
I disagree with your assertion that my hypothesis can’t be tested. Certainly one can’t raise a sample pool in a vacuum in order to conduct a cause-and-effect trial, but couldn’t one work backward from process of elimination by excluding the operative factors from the non-operative ones? I theorize that not only can such a study be conducted but many such studies have been conducted. However, I have now been up far too long without sleep and am too tired to come up with any cites other than the abstracts I’ve already dug up. I’ll conduct a more thorough search for supporting evidence after a long nap if anyone really desires.
Since no one else is attempting to provide a factual answer I’ll have to take a stab at this.
Studies of girls who have CAH/AGS (congenital adrenal hyperplasia / adrenogenital syndrome) indicate that there are in fact innate differences between males and females. Girls with AGS produce excess androgens (e.g. testosterone) in the adrenal gland, leading to masculinization of the external genitalia. This is usually corrected surgically at birth. From that point on, they have basically the same environment as other little girls.
But that early exposure to testosterone appears to affect them for life. They are more likely to become “tomboys”, have less interest in playing with dolls, are less interested in cosmetics and clothes, are less interested in becoming wives/mothers, are more likely to have sex with other women, and are more aggressive in general. They seem to have “male” brains.
Actually, I’ve already read this study. You may wish to note that this study STILL does not and can not verify that behavior is biologically related in humans. With a sample size of 17 affected individuals and a control group of 11, they have not isolated these individuals from a social structure that influences them. Their parents knew they’d had genital surgery and may have reported them as being more “male” acting than other syblings only because they EXPECTED them to be.
Problems with this research:
The sample and control groups are too small to extrapolate to the entire population.
There’s no indication of WHAT they considered aggressive behavior. Since people are more likely to call boys’ play aggressive and girls’ play “spirited” even when they are basically duplicates, there could be error here. We don’t have any way of knowing, because we can’t see what they used as a measure of what equals aggression, what was used to indicate “disinterest” in “female” activities, etc…
The study participants were too young to be appropriate for the questions asked. Girls between 4.3 and 19 years old are not all that likely to be interested in “infant care” or to daydream about weddings and marriage, in spite of what you learned from Barbie doll commercials. We have no idea what percentage of those polled have even gone through puberty. The study could have been done with 16 four-year-olds and one 19-year-old for all we know.
Even this late in the history of scientific research, it’s often difficult to give a cause and effect relationship of hormones and behavior. Did excess testosterone create an aggressive behavior, or did the aggressive behavior cause excess testosterone production? Most times, we don’t know.
It’s a long, long way from rats to humans.
This still does not answer the OP’s question regarding brain structure. It only indicates that hormones have an affect on behavior (and does so with the problems indicated above), not that men and women have different brain structure that causes them to have different preferences and engage in different behavior.
As a father of both boys and girls (and every parent I have talked to about it) I have no doubt that the difference in behaviour is mainly biological, with some overprinting by environmental factors.
A good judge is - is the behaviour universal? Joy, anger, jealousy, etc are found in everyone. They are thus definitely “innate” brain-hard-wired-from -birth traits
The fact that women of all cultures and ages are worse at 3-D problems, but better at verbal skills strongly suggest a difference from birth.
“nature” makes mens and womens bodies very different (thank god). I see no reason why it didn’t make the brains diferent as well
Oh, so you meant “Why shouldn’t we believe this if we had proof that it was true?” No reason. The only problem is, we don’t have such proof. There has been no such scientifically valid experiment with properly interpreted data, and it is highly unlikely that there ever will be given the difficulties in staging such an experiment.
**
No. There are too many environmental factors and no practical way to control most of them.
First of all, what SexyWriter said.
Secondly, that description sounds an awful lot like me, and I have a hormone condition that (among other things) caused me to have abnormally low testosterone levels for most of my adolescence at the very least, and possibly my entire life up until I went on hormone medication at age 19.
I have rarely seen topics on this board stuck at a level of foggy grasp of the facts and simple childish bickering. Let’s start over very slowly for those of you that have read a magazine, newspaper, or seen the news in the past 50 years or so.
First of all, my graduate work is Sexual Differentiation in the Department of Behavioral Neuroscience at Dartmouth. Let’s think about that for a minute. The fact that an Ivy League university has professors that specialize in sexual differentiation of the brain must indicate that there is something there to be studied. As a matter of fact, almost all-major research universities have researchers working in this field. It has been a hotbed of research for the past 15 years or so.
Just like all basic biological research, the studies are conducted in ANIMALS before they are extrapolated to humans. The volume of research that outlines the sexual differences in the rat brain alone would fill a small library. Sexual differences can be found at the gross morphological level (the corpus callosum and certain areas of the hypothalamus show measurable differences in size by sex unrelated to overall brain size. Many other areas of research have found differences in concentrations of neurotransmitter receptors (e.g. GABA, seretonin). I worked on several such studies myself that found these sex differences and later correlated them to behavior.
Such studies are also done in humans although not as commonly. Simon Levay found one area of the anterior hypothalamus (INAH3) in males that may be a marker for male homosexuality. These results were described in his book The Sexual Brain. MRI studies have found the same differences in corpus callosum as found in the animal models.
Yes it is harder to do definitive research in humans for brain studies but this is true for almost all other types of biological studies.
Finally, you die-hard skeptics that don’t believe that we can prove that there are any brain differences between males and females that can be correlated with behavior then I must say that you are simply in denial. The hypothalamus and pituitary in the female control the menstrual cycle in the female while they obviously don’t control this function in the human male. This regulation is controlled through a feedback loop of estrogen and progesterone that go through a well-defined cycle every month to control ovulation and menstruation. Both of these hormones also have had measurable effects on behavior in countless human and animal studies.
Thank you, Shagnasty, my academic knight in shining armor! I knew if I held on long enough someone could and would come along to back up my idle speculation with cold hard fact. Here endeth the thread, and any further discussion belongs squarely in IMHO territory.
I don’t believe that anyone here has claimed that brain structure has no affect on behavior, or that there are no brain differences between men and women, merely that it is difficult if not impossible to tell which differences are purely biological and which have been influenced by environmental factors.
I am sure you must know that the menstrual cycle and its associated effects vary dramatically from woman to woman. I am sure you must know that a woman’s environment can affect this. I am sure you must know that some women never menstruate at all. I am sure you must also know that men experience hormone fluctuations as well. Knowing all this, what I am not sure of is your point is.
I believe that male fetuses have more asymmetric brain hemispheres than female fetuses do, before society has had a chance to do anything. Also, if there is no innate difference between mens’ minds and womens’ minds, transexuals have their head up their ass: How can someone be a women’s mind trapped in a man’s body if womens’ and mens’ minds are the same? I doubt their parents raised them as the opposite sex!
Slight hijack. When my son was little, we did not buy his toys according to sex roles. We gave him cars, we gave him dolls, we gave him stuffed animals. He, seemingly on his own, gravitated toward the cars. So what does this mean, that boys are inherently attracted to cars and trucks? What would be the evolutionary reason for this? “Millions of years ago, our primitive ape-like ancestors hunted the vast herds of dump trucks that once roamed through Olduvai. <Cue National Geographic theme music.>” I’m with Lamia: There are innate differences, but figuring out what they are is fiendishly difficult.