HOW THE HUMAN BRAIN FUNCTIONS

Brain is an ever growing organ. It continues to grow irrespective of the age. So far, it was believed that the brain's growth is maximum till one enters in his twenties. Thereafter, the growth rate slows down and after sixties, one has a negative growth, i.e. the deterioration starts. But the modern scientific discoveries have established that growth of Brain is not affected by the age factor. The brain will continue to grow as long as it is stimulated by effortto learn new things, environment and proper foods etc. On the other hand, our mental powers can wither away by disuse, boredom and lack of self-confidence and improper diet.

Our brain consists of about 100 billion cells, strung together by electric fibers and axions. Dendrites make electrical impulses into the nerve cells and axions carry signals from cells to other neurons. The all neurons (brain cells) taken together, equate to 20 watts of electric power, the amount consumed by a dim light bulb.

The circuits between each cell are broken by a minute gap, known as a synapse and there are about 100 trillion of synapses. Both depression and Parkinson's disease are linked to a problem with transmitters at synapses and drugs are sometimes prescribed to control neurotransmitters. Other naturally occurring chemicals also play a role in regulating the brain. Hormones, for example, are chemical messengers that travel through the blood to regulate organs and tissues. In fact, the brain acting through the pituitary gland is itself the hormone producing gland in the body. By releasing chemicals into the bloodstream, it can reach sites that are beyond the network of local nerves. The brain itself can also be influenced by the hormones it is responsible for releasing. On such chemical is adrenaline, which prepares the body for action by speeding up heart rate and prompting release of blood sugar from the liver, and also gears us up mentally and focuses and narrows attention. There are other such brain chemicals such as neuropeptides, which influence memory and sexual behaviour, endorphins which affect the experience of pain and pleasure etc.