SOURCES: Dr. Jay Giedd, Chief of Brain Imaging, Child Psychiatric Branch—NIMH; Paul Thompson; Andrew Lee; Kiralee Hayashi; Arthur Toga—UCLA Lab of Neuro Imaging and Nitin Gogtay; Judy Rapoport—NIMH Child Psychiatry Branch. TIME Diagram by Joe Lertola. TIME.com graphic by Garrett Rosso. The Image Bank—Getty Images
FROM THE MAY 10, 2003 ISSUE OF TIME MAGAZINE; POSTED SUNDAY, MAY 2, 2003

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