Bioethics News

Human sexual dimorphism. Do men and women also have different brain structures?

There are differences in the brain structure between men and women. The brains of adult males are 14% larger than female brains, with larger ventricles and a higher ratio of white grey matter; however, no differences were found in the hippocampus

Some time ago, we discussed an article by Martínez-Morga, Felipe Navarro and Salvador Martínez, from the UMH-CSIC Institute of Neurosciences in Alicante (Spain), in which the structural differences in the brain of men and women were confirmed, stating that: “The brain is the most complex organ in the body, on which mental functions and behaviour depend. It is evident that the differences that characterise the behaviour of males and females in vertebrates are due to the existence of structural differences in the brain. Today, a fair amount is known about the molecular and cellular bases that underlie the development and maintenance of these differences, and therefore, of the neurobiological bases of the differential behaviour between males and females of the same species”.

“It has been shown that the production of gonadal hormones during development acts on specific receptors that regulate processes that are essential in genital development during the early stage of development, and on the central nervous system during the perinatal stage. In the embryonic brain, the action of these hormones regulates neurogenesis and cell death in localised regions. The neurons and neural circuits in these regions are fundamentally implicated in the control of autonomic responses and motor reflexes with clear sexual dimorphism, as well as in more complex brain functions that determine the identity and sexual behaviour of the individual.

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