CNNW Sanjay Gupta MD September 27, 2014
Five weeks old it is the size of an apple seed but the brain has begun to grow. By eight weeks the Central Service system is in place. The network is spreading out and nerve signals traveling more than 150 miles per hour. At birth nearly all 100 billion neurones of the human brain are in place. The brain only weighs about 25 of what it will later on. Its about to embark on its Fastest Growing period, quadrupling in size by the time a child finishes preschool. By age 6 the brain is 90 of its adult size. During that burst of growth 700 new connections are formed every second as we gain the capac...
Source: archive.org
