By measuring activity in different parts of the brain, neuroscientsts can get a sense of how some people will respond to treatments. John Lund/Getty Images hide caption

itoggle caption John Lund/Getty Images

Elizabeth, Samuel, Bryan and Noah Shaw amid Texas bluebonnets on Easter Sunday. Samuel was conceived with in vitro fertilization so he would not suffer from the hereditary cancer that afflicted Noah. Courtesy of Elizabeth Shaw hide caption

itoggle caption Courtesy of Elizabeth Shaw