Know The Hardware (Nervous System - VII)

Differences in the brains of males and females:

 

Total brain size:

In adults, the average brain weight in men is about 11-12% MORE than the average brain weight in women. Men's heads are also about 2% bigger than women's. . This is due to the larger physical stature of men. Male’s larger muscle mass, and larger body size require more neurons to control them. This does not suggest that due to the larger brain, males are smarter than females.

 

Cell number:

men have 4% more  brain cells than women , and about 100 grams more of brain tissue. this may explain why women are more prone to dementia (such as Alzheimer's disease) than  men, because although both may lose the same number of neurons due to the disease, "in males, the functional reserve may be greater as a larger number of nerve cells are present, which could prevent some of the functional losses."

 

Cellular connections:

while men have more neurons in the cerebral cortex, women have a more developed neuropil, or the space between cell bodies, which contains synapses, dendrites and axons, and allows for communication among neurons .

 

Corpus callosum:

it is reported that a woman's brain has a larger corpus collusum, which means women can transfer data between the right and left hemisphere faster than men. Men tend to be more left brained, while women have greater access to both sides

 

Language:

two areas in the frontal and temporal lobes related to language (the areas of Broca and Wernicke) were significantly larger in women, thus providing a biological reason for women's notorious superiority in language-associated thoughts. For men, language is most often just in the dominant hemisphere (usually the left side), but a larger number of women seem to be able to use both sides for language. This gives them a distinct advantage. If a woman has a stroke in the left front side of the brain, she may still retain some language from the right front side. Men who have the same left sided damage are less likely to recover as fully. Curiously, oriental people which use pictographic (or ideographic) written languages tend also to use both sides of the brain, regardless of gender.

 

Inferior parietal lobule (IPL):

it is a brain region in the cortex, which is significantly larger in men than in women. This area is bilateral and is located just above the level of the ears (parietal cortex). Furthermore, the left side IPL is larger in men than the right side. In women, this asymmetry is reversed, although the difference between left and right sides is not so large as in men. This is the same area which was shown to be larger in the brain of Albert Einstein, as well as in other physicists and mathematicians. So, it seems that IPL's size correlates highly with mental mathematical abilities. Studies have linked the right IPL with the memory involved in understanding and manipulating spatial relationships and the ability to sense relationships between body parts. It is also related to the perception of our own affects or feelings. The left IPL is involved with perception of time and speed, and the ability of mentally rotate 3-D figures .

 

Orbitofrontal to amygdale ratio (OAR):

In one project, they measured the size of the orbitofrontal cortex, a region involved in regulating emotions, and compared it with the size of the amygdala, implicated more in producing emotional reactions. The investigators found that women possess a significantly larger orbitofrontal-to-amygdala ratio (OAR) than men do. One can speculate from these findings that women might on average prove more capable of controlling their emotional reactions.

 

Limbic size:

females, on average, have a larger deep limbic system than males. This gives females several advantages and disadvantages. Due to the larger deep limbic brain women are more in touch with their feelings, they are generally better able to express their feelings than men. They have an increased ability to bond and be connected to others. Females have a more acute sense of smell, which is likely to have developed from an evolutionary need for the mother to recognize her young. Having a larger deep limbic system leaves a female somewhat more susceptible to depression, especially at times of significant hormonal changes such as the onset of puberty, before menses, after the birth of a child and at menopause. Women attempt suicide three times more than men. Yet, men kill themselves three times more than women, in part, because they use more violent means of killing themselves (women tend to use overdoses with pills while men tend to either shoot or hang themselves) and men are generally less connected to others than are women.