The Brain

The human brain weighs about 3.5 pounds. During the first six months of a baby's life, its brain doubles in size. A man's brain is heavier than a woman's brain. People's brains weigh more now than they did 100 years ago. Brain cells use up a lot of energy, so they need a constant supply of oxygen. The brain weighs one-fiftieth as much as the body, but uses one-fourth (25 percent) of the body's oxygen.

The brain can store 100 trillion pieces of information. In each second the brain receives more than 100 million nerve messages from the body. The brain loses 1,000 cells per day, which are not replaced, and yet memories are maintained.

The brain cannot feel pain. If a surgeon operates on the brain, the patient feels no pain.

The left side of the brain controls the right side of the body; the right side of the brain controls the left side of the body. Each hemisphere of the brain receives information about the opposite side of the visual field. If you are a right-handed, you have a strong left brain; if you are left-handed, you have a strong right brain. The left brain controls math, language, and logic. The right brain controls art, color, and music. A jazz musician has a dominant right brain. When you play a game of chess, you use the left side of your brain.