Genetic differences in brain development
-By Timothy Lyons
The brains of humans are considered sexually dimorphic. This means that the brains of males and females are different due to Genetic differences in brain development (Britannica.com, n.d.). The differences are often looked at in how they stop functioning when there is damage to either male or female brains. A female’s brain has more connections than a male’s brain in that functions of the brain are shared more readily (Carson & Birkett, 2017). This idea is backed up by the fact that when males sustain stroke damage to an area of the brain that deals in language, the male is
The male’s brain is larger on average than a female’s. There are areas in the brains that have different shapes dependent upon gender. The telencephalon and diencephalon are different in both genders. The corpus callosum appears to have differences dependent upon whether a person is male of female (Carson & Birkett, 2017).
From (Carson & Birkett, 2017) we can see that there are also size differences in an area of the brain known as the medial preoptic/anterior hypothalamic area which was larger in males. There are also differences in the suprachiasmatic nucleus, parts of the hypothalamus, and the anterior commissure. There is also an area of the forebrain known as the bed nucleus of the stria terminalis is larger in males.
Behavior differences due to brain development
Females can have better outcome from brain damage due to their increased capacity for sharing brain functions, as well there are a number of behavioral differences that may be due to development. In (Carson & Birkett, 2017) there are a number of gender and sexual orientation behaviors that seem to be affected by brain changes. It is posited that many of the brain changes that occur are due to the level of in utero exposure to male hormones. In many cases these changes result in preference for sexual partners and even smells of androgen and estrogen by males and females as evidenced by studying the brains of homosexuals and linking the brain changes in reference to male versus female brain differences. This also include studies that looked at the size of areas of the brains of transgender females and males that linked the brain sizes to genetically female persons who identify as female and males who identify as males respectively.
Another area that may be a factor in genetic inheritance of brain differences is maternal and paternal behavior. This information from (Carson & Birkett, 2017) shows that there are secretions of hormones that take place in the females that produce nesting and bonding with children in female rodents. This type of behavior does not normally occur in mammalian males.
References for Genetic differences in brain development
Alvandi, E. O. (2016). A Review on Meanings of Emotions: Steps to a Neural-Informational Notion of Semantics. Cognition, Brain, Behavior, XX(1), 45-63.
Britannica.com. (n.d.). Sexual dimorphism. Retrieved January 29, 2017, from https://www.britannica.com/science/sexual-dimorphism
Carlson, N. R., & Birkett, M. A. (2017). Physiology of Behavior (12 ed.). Boston, MA: Pearson Education.
Hayes, S. C., Strosahl, K. D., & Wilson, K. G. (2012). Acceptance and Commitment Therapy (2nd ed.). New York, NY: Guilford Press