Hello again, it's been a while so I thought I'd drop in a comment or two about what I've found recently in the news about neurobio. I've lately been reading about neurotransmitters and how they bind to sites in specific neurons, instigating depolarization across the membrane of the neuron and allowing for an action potential to communicate to hundreds of thousands of other neurons. This communication between neurons in the central nervous system is relayed into actions in the peripheral nervous system resulting in behavior. But how is this synchronized? What neuron does what? What must be connected to what and why? These are all questions that may take a while to be answered, but we are finding new developments everyday.
In an article from Cornell News, I read about an experiment by James Goodson and Andrew Bass (2000) in which neurotransmitters' role in the display of sex characteristics in plainfin midshipman fish were examined. In this particular fish, males will make vocal calls through the water that attract females who will come to the site to lay eggs for the vocalizing male to fertilize. However, a second type of male that is unable to make vocal calls waits nearby so that once the eggs are laid, he can get some free-fertilization-action.
Goodson and Bass anesthetized and stimulated the anterior portion of the hypothalamus in each fish to stimulate either a vocal call, or the female's short grunt (a response to the male's call). After stimulating normal calls in each fish, the neurotransmitters isotocin and vasotocin (identical to the mammalian oxytocin and vasopressin) were administered to the anterior hypothalamus of each fish. When administered, fish that normally could make calls lost the ability to do so and developed female like grunts, similar to the type II males that could not call but rather grunted like females. This meant that a trait that was typically thought to be controlled by sex (controlled or linked by the gonads) was actually independent, and regulated completely by the brain.
Who knows how many of our traits are linked to gonad development, probably much fewer than we might originally think. If I was given a good dose of estrogen would I not want to play football or wrestle with my best friends?...doubtful (it might just turn into flag football with the Vikes or a pillow fight). At any rate, we shouldn't be so quick to make judgment calls on biology's effects in gender behavior.
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Check out the work on blue-headed wrasses as well. These fish change sex, i.e., large females can become large territorial males when such a male gets eaten, etc, so the territory is free. "Sneaker" males can grow and become colorful and territorial as well. Gonads are involved in the sex-change of color, but not in changes in behavior.
"Who knows how many of our traits are linked to gonad development, probably much fewer than we might originally think. If I was given a good dose of estrogen would I not want to play football or wrestle with my best friends?...doubtful (it might just turn into flag football with the Vikes or a pillow fight)."
Nah, you'd just grow breasts.
You seem to be making (albeit light-hearted) normative assumptions in your final paragraph, as you try to relate the above to humans. I think this is a mistake. Socialization plays a -very- large role in human behavior, and the social pressures for men to act like X and for women to act like Y are quite strong... and difficult to deconvolute.
Probably best to wait for -much- better data on human sexuality before speculating along those lines.
There is actually a lot of *anecdotal* information about behavioral changes with the administration of estrogen and withdrawal of testosterone [spironolactone or orchiectomy]in reports of transgender male-to-female transsexuals. The same can also be said for female-to-male transsexuals with testosterone and withdrawal of estrogen. How much of this could be a placebo effect from expectations/socializaion is unknown and will probably remain so. Which of these transsexuals would submit to a double-blind study?
Does anyone know if there is literature on socialization and chemical differences. I'm sure the neurochemistry must change some, but could that effect hormones?
Bass?! Excellent name for a fish researcher.
I wouldn't say they cause "behavioral changes", but cross-sex hormones defiantly have a mental effect. In regards to mood and temperament.
I wonder if the results of, for instance, the Stanford Prison Experiments, might be relevant here as regards the spectacular influence that roles and internalized expectations can have on behavior? (Actually, it's refreshing to see someone bring up this bit of research and even consider the possibility of it being placebo-effect; it appears to have occurred to neither my Human Sexuality professor nor our resident biological determinists).
I don't think the placebo effect applies. Transsexuals don't take hormones to change their behavior. They take them mostly for the physical effects. There's no expectation that they'll suddenly adopt stereotypical traits of the target gender. They already consider themselves that gender before hormones come into the picture.
Reuters just had a story about something similar in C. elegans:
http://www.reuters.com/article/scienceNews/idUSN2535476120071025?sp=true
I haven't read the paper, and I see some signs of weird oversimplification in the story, but it sounds interesting and apropos. Maybe PZ will do another C. elegans explication of the source paper... (hint, hint)
Not "placebo effect" so much, but looking like the target gender = being treated like the target gender, and the Stanford Prison experiments among others suggest that the expectations others have of people, as conveyed in their treatment, can have a fairly huge effect on those people's behavior and self-concept. This isn't the most elegant phrasing, but it's a confounding factor the CBDs seem determined to ignore.
Well, to an extent. I see your Stanford Prison Experiment and raise you one David Reimer case study.
Protip: Anyone justifying human (mis-)behavior on the basis of the behavior in question being "natural" is talking out of their ass.
At any rate, we shouldn't be so quick to make judgment calls on biology's effects in gender behavior.
Our judgment calls should be based on the evidence, and there is very strong evidence that biology has a large effect on gender behavior. This isn't even a very controversial fact with respect to animal behavior. It's usually only when human behavior is involved that ideology gets in the way of reason.
Well, to an extent. I see your Stanford Prison Experiment and raise you one David Reimer case study.
The irony is that psychology students in the 70s were taught that the Reimer case confirmed that gender roles and identity are learned.
The Stanford Prison Experiment suggests that vulnerability to dominance hierarchies is a deep aspect of human nature, which is consistent with our primate heritage and many other aspects of human culture.
I don't know; I'm pretty sure that if the roles of cows or hens in society were changing that resentment of that change would drive a lot of premature, overreaching, and selective conclusions about them, too.
What premature, overreaching and selective conclusions would those be, and who is making them?
Isn't it remarkable how a simple lack of care can turn a perfectly reasonable statement into some offensive bigotry in one's memory?
Well, in some people's, at least.
Caledonian: Given the rather fledgling state of real scientific research on this sort of topic and the history of attempts to dismiss the institutionalized (de facto as well as de jure) social and economic inequality of certain groups as inevitable due to the claimed "nature" of members of those groups (and therefore acceptable), what is unreasonable about classifying the latest ones as offensive bigotry?
Azky,
... what is unreasonable about classifying the latest ones as offensive bigotry?
What "latest ones?" What statements are you referring to? By whom? Or is this all just a product of your fevered imagination?
A good example of what happens when political and social ideology blinds people to reason is John Money, the scientist who worked with David Reimer. Money was a leading proponent of the idea that gender roles and identity are created socially rather than being in any significant sense innate. It now appears that Money was so wedded to this discredited view that he deliberately suppressed conflicting evidence and pressured Reimer's parents into consenting to sex change surgery on the boy. They refused, but by then the damage of trying to "socialize" Reimer into a female gender identity had been done, with tragic consequences.
I'm surprised to find out the gender roles are not socially constructed. Really, really surprised. You don't mean sexual identity in the above, correct? You mean the actual ideas about what a woman should be like, what a 'real man' is...? Is there some biological difference between communities that gives each group its unique set of gender roles? some difference between Saudi Arabian women and North American? Between medieval Norsemen and modern cubicle-potatoes?
John B:
Of course there are some culturally determined aspects of gender roles. My guess is that the difference between the medieval Norsemen and the modern cubicle-potatoes is primarily a social one. But (as much as I would like it to be true) the PC concept of gender being entirely a social construct just doesn't hold up.
If gender were entirely socially constructed, there could be no transgendered people or people such as David Reimer, who never truly identify with their perceived gender. There must be something else going on.
I see, you're only disputing the idea that biological differences between men and women play no role in gender identification. Okay, I don't think we know enough about the whole nature vs. nurture thing to positively rule anything out.
Thank you for making the concession, John B. That sort of rationality is rarer that I'd like.
You're welcome, Caledonian. As I was writing my reply I realised there was a danger that I was trying to paint Jason or others into an extreme position they never advocated ('social construction of gender as a discredited view' as opposed to rhian's less extreme 'If gender were entirely socially constructed').
The problem with studying too much social constructionism is the temptation to forget it only makes sense as a methodological reduction, and cannot speak to the non-sociological elements of phenomena. It doesn't offer any ground to reject biological determinism. At best it offers an alternate account that people might find more plausible... which is not the same thing as actually refuting the idea of some biological influence.
I would have ended up saying things like "you have no reason to believe it wasn't entirely social" which kind of puts them in the position of proving me wrong... a dick move.
Hello? There is a lot of physical anatomy that is different between males and females at birth. Is there any reason what so ever to assume that there are no differences in neuroanatomy? If anything, neuroanatomy is easier to change, and so is likely to be more plastic and hence more complicated because the brain need to do things that are a lot more complicated than rub together, deposit or receive gametes and provide a niche for them to grow to term.
I don't think the question is whether or not there are differences in neuroanatomy, but rather, whether or not those differences have a measureable (some might prefer 'significant') effect on gendered (social) identity and behaviour... things a theory of socialization couldn't account for.
"Measurable", or "significant", what is the point? It is pretty obvious that neuroanatomy matters, and that socialization also matters. It is equally obvious that the relative importance of those different factors is going to be different with different genotypes, different phenotypes, and in different environments. The "result" is due to the coupled interactions of a large number of non-linear parameters. Such systems exhibit chaotic behavior. The outcome is fundamentally non-predictable from the starting conditions even when every parameter is completely known in complete detail. Actually none of the parameters are known in complete detail and many of them are completely unknown.
It is extremely obvious (to me anyway) that the very complex neuroanatomy at birth cannot be meaningfully described by a single word, "nature". It is equally obvious that the totality of the environment and exposure that an individual is exposed to from birth to the present cannot be meaningfully described by a single word "nurture".
Trying to argue which is more "important" (when they are obviously coupled and non-linear) is like arguing which link in a chain is most important. It is more about how people want the world to be perceived, rather than how the world actually is. In the Reimer-Money case, Money could simply say "the socialization wasn't done right".