Support WBUROur Brains Are Shrinking. Are We Getting Dumber?Play04:45Download AudioNPR StaffJanuary 02, 2011 ShareToday's human brain is about 10 percent smaller than the Cro-Magnon brain from more than 20,000 years ago. (iStockphoto.com)
Today's human brain is about 10 percent smaller than the Cro-Magnon brain from more than 20,000 years ago. (iStockphoto.com)