Original  Article

Human Brain Sexual Dimorphism: Causes and

    Consequences

Dr. Desmond Gilmore*

ABSTRACT

Several sexually dimorphic  areas  have  been  identified in the central  nervous system (CNS) of many mammals  and  birds.   Androgens and their metabolites,  acting during limited critical periods in fetal or early neonatal  life, are largely responsible for the gender  differences seen in both the brain and reproductive tract. Not only are a number of structures in the human  CNS irreversibly altered by the early action of androgens, but so  is  an  individual’s future  sexual  and  other  types  of  behavior.     Considerable   evidence  has  now accumulated to indicate that sexual orientation is largely determined by hormonal  action on the brain early in life,  but  a  genetic  component   is  involved  as  well  and  environmental influences  during  childhood  and adolescence also have an important role to play.

Key words:  brain dimorphism sexual orientation.