When it comes to gender changes, the human brain is not excluded. Researchers have shown there exist some morphologic and functional changes between two sexes. From estrogen brain receptors to different ways of analyzing and verbal usage brain plays its genetic programmed role, where many factors play the role, including gender.

Studies have shown that the human brain, as well as the human body,  is a sexually dysmorphic structure.The term sexual dysmorphism itself indicates several changes according to gender which include different characteristics such may be body muscle mass, the spread of the body hair and even behavioral changes.

In 2000 a theory was developed based on language function suggesting that woman use both hemispheres equally, while men use lateralized to the left hemisphere strongly, but in 2008 scientist turned this theory down claiming there was no difference in this aspect between male and female brain.

Another study took place in 2013 and the researchers revealed that the supratentorial region was greater in the female brains while male brains “dominated”   the inter-hemispheric connectivity and a reverse effect in the cerebellar connections. These changes are measurable after the age 13. The result of these structural changes suggested that the male brains are designed to have a facility in perception and coordinated actions, on the other side female brains are likely to have more connections in the intuitive and analytical process.

Another interesting result came from neuroscientists who made an experiment to examine the effects of the stress condition in the male and female brain. The result revealed that the female brain performance is reduced under stress conditions while the male's one enhances and as a consequence of its influence on the cognitive reasoning female use more verbal strategies than men. All of this comes from the activation of the hippocampus which in women is dominated on the left side, while in man on the right one.

According to all of this morphologic changes, scientists have done deeper research of the hippocampus relation with other structures in the brain and found out it plays a major role in learning which is also considered a sexual dysmorphic function.

The dysmorphism comes from the neurochemicals and different hormone levels released in this area. For example, an estradiol-linked in utero development indicates that neurogenesis in the female is lower in the hippocampal region  (  neurogenesis is the synthesis of new neurons ) than in men, because the estradiol levels are higher.

Estradiol, in a dose-sensitive manner also influences learning and memory by enhancing them in postpartum life (life after birth).

Another hormone found to have a great impact in developing is estrogen, which receptors are found in different brain regions and its role in brain development is linked with feminizing and defeminizing effects. Those brain region mentioned to have this kind of receptors are the cortex of the frontal lobe, pituitary gland, hypothalamus, and hippocampus. High levels of this hormone in the male brain during development enhances neuronal growth, while for the same process in the female brain is required a moderate hormone level.

The female brain is protected by defeminizing effects of estrogen by the alfa-fetoprotein  presence, which serves as a carrier protein of estrogen and allows it to be transported into brain cells to provide a normal neuronal growth.

Other hormones also are positively correlated with brain functional changes such are behavior, social interaction and sexual behavior  (for example oxytocin ).

In the end of the day, all we are is molecular interaction so don’t be surprised if you discover that between two sexes there exist differences in those interactions which do nothing more than defining who we are.

 

COPYRIGHT: This article is property of We Speak Science, a nonprofit institution co-founded by Dr. Detina Zalli (Harvard University) and Dr. Argita Zalli (Imperial College London). The article is written by Arda Gjermeni ( Medical University, Tirana) 

 

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