;-)
The interactions of environment - writ large - and brain chemistry - writ large - are very much a topic of research. The Behavior Genetics people face a major problem separating the two for analytical purposes. My opinion is the two are so intimately connected it is impossible to achieve a valid Categorical distinction. For example, that Danish study on schizophrenia showed the highest level of children developing the dysfunction was when they had a genetic disposition for it (9%) AND there was an environmental (parental) exhibition of the dysfunction (16%.)
Enculturation (Environment) studies of African American and European Americans show the WORST possible outcomes of Public Policy stem from policy and decision makers being uninformed by the Body/Mind Unity and an over-reliance on - let me put it - "tenuous" conclusions from Behavioral Genetic (BG) reseach. The same happens with BG Gender Differences studies as applied to educational policies and practices for girls, notably in regards to mathematical education.
It's possible to go one step further and question a definition of "normal" - aka, that which no one is - based on Information derived from the extremes. Schizophrenia is a disabling disease. Those who are schizoid have some of the Attributes and Properties of schizophrenia but are typically high functioning with regard to cognition, social intelligence, and RW skills. It can be stated the "male" brain has a tendenz for schizoid because it is a "male" brain plus Environmental influences that support "male" brain behavior, including but not limited to, "male-as-gender" socialization. It is here that it is possible to really study, gain knowledge, for informing Public Policy. With schizophrenics about the only intervention is: drugs or, at worst, institutionalization. With schizoids there are Public Options (that may be) available for those at or approaching dysfunction.
But we don't know because most of the research is directed at the extremes.
Yeah, except that
An extension, the extreme male brain theory, hypothesizes that autism is an extreme case of the male brain, defined psychometrically as individuals in whom systemizing is better than empathizing; this extension is controversial, as many studies contradict the idea that baby boys and girls respond differently to people and objects.
The same is applicable across all levels of Environment and Environmental influences.
Toss in Biology plus Environment, the division into narrow fields, disciplines, and sub-disciplies and the whole thing gets squishy.
Extreme "male brain" theories are, let me put it, wrong headed. We don't know enough to make those kind of conclusions. People study them because they limit the scope of the investigation. I concede there is a utility there, gotta draw the line somewhere, but to then recursively wander back to a gross generalization of the entire subject population is more than a bit intellectually pretentious.
We've been here before with the Social Darwinism, eugenics and ethnographic movements of the 1880-1945s. It was a disaster, from both scientific and humanitarian considerations. Yet there was useful work: clinical therapies for Hypothermia and deep insights into the epidemiology of Sexual Diseases, to name two, that resulted. But at what a cost!
And, too, there are some personal experiences, that I don't need to get into, driving my intellectual position. (If ya remember what I'm referencing. ;-)
So when we start talking about tendencies that's ALL we're talking about. And we're talking low-order tendencies, to boot, spread across the entire test or subject population.
