Top schools like Harvard, seen here in 2000, often offer scholarships and other financial incentives, but they are finding it hard to increase the socioeconomic diversity on campus. Darren McCollester/Getty Images hide caption

itoggle caption Darren McCollester/Getty Images

George Zimmerman (left) and his attorney appear in court for a bond hearing in June. Zimmerman's case sparked a nationwide debate about so-called "stand your ground" laws. Joe Burbank/AP hide caption

itoggle caption Joe Burbank/AP

Posting a picture like this on the fridge might seem like good motivation for weight loss. But scientists say it might instead inspire weight gain. iStockphoto.com hide caption

itoggle caption iStockphoto.com

Does This Guy Matter? Conductor Leonard Bernstein during rehearsal with the Cincinnati Symphony at Carnegie Hall in 1977. James Garrett/New York Daily News via Getty Images hide caption

itoggle caption James Garrett/New York Daily News via Getty Images

Allan Lichtman, a professor at American University, discusses his 13 keys to a successful election campaign on April 13 in his office in Washington, D.C. Paul J. Richards/AFP/Getty Images hide caption

itoggle caption Paul J. Richards/AFP/Getty Images

Is there an angel or a devil behind the mask? Scientists say it may not matter in terms of anonymous behavior. Joel Saget/AFP/Getty Images hide caption

itoggle caption Joel Saget/AFP/Getty Images

Abraham Lincoln, circa 1850. Lincoln was a political non-entity before he was elected. Why is he more widely known to history than the presidents who came immediately before and after him? Hulton Archive/Getty Images hide caption

itoggle caption Hulton Archive/Getty Images

Matt Langione, a subject in the study, reads Jane Austen's Mansfield Park. Results from the study suggest that blood flow in the brain differs during leisurely and critical reading activities. L.A. Cicero/Stanford University hide caption

itoggle caption L.A. Cicero/Stanford University