Why do we have a brain?

Brain - the brain directs and coordinates movements and reflexes, registers sensations and is the supreme nervous organ by which man acquires knowledge and the power to use and adapt it. It shapes our personalities, and without it we would be more helpless than the tiniest human baby. There are three main parts of the brain: the forebrain (or cerebrum), the midbrain and the hindbrain. They have the consistency of soft jelly and are protected by three membranes (meninges), a tough outer envelope called the dura and a watery fluid (cerebrospinal fluid) which acts as a support and a cushion. The brain is connected to the spinal cord, and its surface is highly convoluted. The cerebrum, which forms nearly nine-tenths of the brain, is divided into to two halves (hemisphere). Generally the left half of the cerebrum controls the right half of the body, Some areas are connected with the special senses of man, but there are so called "silent areas" which scientists believe are connected with memory and the association of ideas. The thalamus, a mass of grey matter which is buried in the cerebrum, is the source of instinctive feeling and emotion. The midbrain is concerned with eye movements, while the hindbrain contains the nerve cells responsible for breathing, heart action, digestive juices and so on. The cerebellum, a part of the hindbrain, plays an important role in the execution of the more highly skilled movements.

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