The Human Brain

The human brain is a fascinating organ that helps define our personalities, our health, communication and social interactions, as well as keeping us alive by directing all of our bio-activities.

­The following amazing facts about the human brain will demonstrate just how sophisticated this organ really is.

Physical Facts About the Brain

The adult human brain weights about 3 pounds and the cerebrum accounts for about 85% of the brain. The brain is composed of 40% gray and 60% white matter. The gray matter is made up of about 100 billion neurons that gather and transmit signals while the white matter is made of dendrites and axons that the neurons use to transmit signals. The brain is composted of about 75% water and is the fattiest organ in the body, consisting of a minimum of 60% fat. Humans have the largest brain to body ratio of any animal, and the blood vessels in the brain, if stretched end-to-end, would be about 100,000 miles long. The neocortex, or language center of the brain, comprises about 76% of the organ.

The Developing Brain

Brain development begins very early in the life of a fetus. The brain grows at a rate of about a quarter million neurons per minute in the first trimester, with brain growth continuing through age 18. The brain of a newborn baby triples in size during the first year. The amount of brain stimulation a child receives can effect brain growth by as much as 25%. If continued mental activity takes place, new neurons will develop throughout the life of a brain.

Brain Function

Brains use about 20% of the total blood and 20% of the total oxygen that is circulating through the body at any given time. If blood supply to the brain is cut off for more than 8 to 10 seconds, loss of consciousness will occur, yet the human brain can survive for between 4 and 6 minutes without any oxygen. The information processing speed of the human brain can reach up to 120 meters per per second, and in a waking state can generate 10 - 23 watts of energy.

The brain is all this and more, providing us with the ability to bond socially with other humans and giving us the facilities for the creativity that makes us the innovators of the animal kingdom.­


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