The biological and mental processes by which we move, think, perceive, learn and remember, are reflections of brain functions.

The brain is the greatly modified and enlarged anterior portion of the central nervous system. It is surrounded by three protective membranes (meninges) and enclosed within the cranial cavity of the skull.

The brain is made up of neurons (or nerve cells) and glial cells. It integrates sensory information and directs motors responses, thus playing a major role in vital activities.

Neurons are constituted of two different and important structures: the cell body and a number of string-like extensions called branchings, the axon and the dendrites.

We will dedicate an special article on the internal structures of the brain and the division of the central nervous system, in the next issue.