The enzyme aromatase (found in ovaries and the brain) converts testosterone to estradiol and other androgens to other estrogens. This single chemical reaction is called aromatization and works as estradiol is a metabolite of testosterone. 

Aromatization

A blood protein found in the plasma of fetuses that prevents maternal estrogen from entering the brain by binding estrogen. Testosterone is not effected so it enters the brain and begins the aromatization hypothesis process. 

α-Fetoprotein

This hypothesis was found after the organizational hypothesis to be true in some rodents. It proposes that androgens enter the brain and are converted to estrogens. Meaning, that estrogen is what masculines the developing nervous system.

Rutgers University

This is a possible explanation for sexual differentiation. The idea is that a single androgen diffuses through all the tissues, and thus, masculinizing both the body and the brain. Androgens are required in development to organize the nervous system but also in adulthood to activate its full effects on behavior. 

Organizational Hypothesis

Breedlove, S. & Watson, N. (2017). Behavioral neuroscience, eighth edition. Oxford University Press.

Learn Before

Related

Learn After