It weighs just about 3 pounds and is incredibly dense and delicate. No wonder people for much of history have been in the dark about gray matter. But scientific advances have begun to unravel some of the brain's mysteries, and government researchers say more has been discovered about the human mind in the past 10-year period than in all the time before it. The result is a better understanding of, and improved treatments for, the more than 600 known neurological diseases.
<<< Select a topic at left to learn about some major problems associated with the brain.
Sources: CBS News, Associated Press, National Institutes of Health, Eric H. Chudler, Ph.D., University of Washington, wikipedia.org, Mayo Clinic, International Consortium for Brain Mapping