April 28, 2014 7:58 pm Selfies May Hold Key to Defining Happiness Researchers at UC San Diego will have access to millions of selfies posted to Twitter to understand what’s behind happiness. NBC 7’s Greg Bledsoe reports. US & World Videos 1:41 ‘The Mummy' turns 25: Remembering the Brendan Fraser classic 1:15 Anna Nicole Smith's look-alike daughter Dannielynn Birkhead attends 2024 Kentucky Derby 3:27 Here's one of the luxurious suites your favorite A-list celebs are getting ready in for the Met Gala 3:27 Dua Lipa claps back at viral ‘give us nothing' meme during ‘SNL' hosting debut 1:07 Britney Spears spotted as authorities respond to alleged hotel incident