During the period of gestation when the brain is forming, levels of testosterone are believed to effect whether a male or female brain develops. This should not be confused with the genetic modification of one X chromosome into a Y chromosome that results in the male-female sexual determination. Typically, a male fetus will have ten times as much testosterone circulating through his system than that found in a female fetus (Wright, Chapter 7). Male or female brain is being used here to describe brain characteristics that are typically male or female. Some research indicates that the brain structure and functioning of homosexual men may more resemble that of a female. For example, it has been reported that the preoptic area in homosexual men is appreciably smaller in homosexual men as compared to that of heterosexual men (Wright, Chapter 7).
The female brain has approximately 15 to 20 percent more gray matter, particularly in the prefrontal cortex, than that of the male brain (Wright, Chapter 5; Wright, Chapter 6; The New Sex Scorecard). A larger percentage of gray matter generally means an increased ability in abstract cognitive functions, higher intelligence, better behavior inhibition and emotional regulation (Wright, Chapter 5). As stated in The New Sex Scorecard, the increased gray matter “provid[es] concentrated processing power – and more thought-linking capacity.”
In the female brain, white matter (less densely packed neurons with a surrounding fatty tissue that create a whitish color), is concentrated in the corpus callosium (The New Sex Scorecard) resulting in a significantly larger corpus callosium than that found in males (Wright, Chapter 7). The corpus callosium connects the two hemispheres of the brain. The larger corpus callosium of the female brain provides a greater level of connectivity between the hemispheres. By way of this increased connectivity, women are better able to utilize both hemispheres for processing. In the male brain, certain functions are controlled in one, and only one, hemisphere of the brain. This bilaterality of the female means that women have increased verbal abilities than those of men (Wright, Chapter 7; The New Sex Scorecard). Women also have a faster blood flow to the brain which “offsets the cognitive effects of aging (Wright, Chapter 7; The New Sex Scorecard).
In addition to brain structure, there are differences in brain functioning between men and women. As mentioned previously, females’ brains tend to function bilaterality – that is they use both hemispheres of their brains to in dealing with conceptual and linguistic matters. Males, on the other hand, tended to be lateralized to the left side of the brain on similar tasks rather than using both hemispheres of the brain on these tasks (Wright, Chapter 7). This, of course, means less ability in these areas because the male hormone (testosterone) slows the growth of the left side of the brain while at the same time accelerating the growth of the right side (The New Sex Scorecard). Research, cited in Wright, Chapter 7, indicates that the structure and functioning of the female brain meant that they were better able to feel and remember emotional experiences, were better organized, and “built for receiving, experiencing, and recalling emotions” (Wright, Chapter 7). Other research has indicated that the functioning of the female brain is such that they are better at counseling, nurturing, and at odor recognition (Wright, Chapter 7). Men, on the other hand, have brain functions that are more prone to aggressive and risk-taking behaviors. This results in men being more competitive, assertive, and attention seeking. Women are comfortable in same-sex relationships, while men tend to form alliances (non-competition agreements, if you will) (Wright, Chapter 7).
These structural and functional differences between male and female brains have implications for criminal and anti-social behavior. Research, cited in Wright, Chapter 7, has indicated that low verbal ability is linked to deviant behavior and criminal activity. Because women have an increased verbal ability (due to the bilateral brain functioning) it is less likely that they will engage in criminal activity. In fact, the statistics on criminal activity bear this out. The female abilities in the emotional arena (e.g. feeling emotions, empathy, etc.) also play a part in the development of criminality, or rather, the decreased level of criminal involvement by women.
Men, because they have a decreased brain function in this area (or lack it all together) are not as likely to feel empathy towards a victim. In other words, their brains are not wired to allow them to put themselves in the place of the victim so as to understand (empathize with) the emotions (fear, sense of loss, etc.) of the victim. (Some Retributive Justice programs seek to teach offenders this “skill” in a hope to decrease recidivism.) The structure and function of the male brain is also implicated in self-control issues. As discussed in Wright, Chapter 7, those with certain brain functioning are unable to learn from discipline (punishment) or to generally learn from their mistakes / experiences. These men may not feel guilt, remorse, or shame. This results in a significant reduction in the brain exercising inhibitory controls over behavior. Deviant behavior is the common result (Wright, Chapter 7). Women, on the other hand, are less likely to commit offenses “due to high levels of internal constraints, particularly moral beliefs, and empathy, that act to inhibit offending behavior” (Wright, Chapter 7). The male’s brain being wired towards more aggressive and risk-taking behaviors also makes them more prone to engage in deviant or criminal behaviors.
It is worth noting, however, that the predisposition, if you will, to criminal behavior is not a foretelling of such behavior. Other factors, such as brain damage or environmental factors which may create negative (or positive) synapses that allow the brain to respond in specific ways to real or perceived stimuli, can affect criminality (Wright, Chapter 6). For example, a child that grows up in an abusive environment may develop specific synapses that result in fear under a perceived threat. Such a person may react negatively to that “threat.” So, a person with such functioning, may when they perceive someone staring at them, may react by becoming aggressive towards that person.
Now, I wonder, if Joseph, that kid from Kindergarten Cop had a father who was a brain researcher, would have said, “Boys have a larger sexually dimorphic nucleus of the preoptic area; girls have larger orbital frontal cortices.” And, would it have been as funny?
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