"Only the hand can tell where it's tender, where the patient winces." — Abraham Verghese James Duncan Davidson/TED hide caption

itoggle caption James Duncan Davidson/TED

For some kids who grow up in poverty, the bond developed with Mom is especially important in dealing with stress. iStockphoto.com hide caption

itoggle caption iStockphoto.com

Giancario Gemignani-Hernandez, 2, of Pittsburgh has his ear examined by Dr. Alejandro Hoberman. Gene J. Puskar/AP hide caption

itoggle caption Gene J. Puskar/AP