The brain is arguably the most complex organ. Its primary function is to direct behavior, and it determines the most appropriate behavior, either consciously or unconsciously, by integrating sensory inputs. It accomplishes this through a complex network of cells, that communicate electrically and electrochemically, to produce discrete, yet dynamic circuits. Therefore, as evidence of the brain's complexity, this organ is the physical substrate of the mind and gives rise to personality.
Although the brain is incredibly complicated, it is important for all persons to gain an understanding of the brain and the nervous system, since keeping a healthy brain is an essential component of maintaining a healthy lifestyle.