Closed Captioning ON OFF apply | reset x Text Display Background Enhancements font Times New Roman Arial Comic Sans size T T T T color share link May 20th, 2014 Study looks at whether cellphones affect brain development Researchers are launching the largest study in the world to find out whether cellular devices affect children's brain development. More video Sponsored Content Now Playing TODAY's Trending: Woman vs. bear vs. kayak Sponsored Content Now Playing Shooting survivor's brother: My sister asked doctor for bullet he removed Sponsored Content Now Playing Stories of survival and heroism from the mass shooting in Oregon Sponsored Content Now Playing Kendra Hatcher murder: Suspected gunman arrested, warrant issued for 'planner' Mental Health Now Playing Social Worker: "Immigration Impacts Generations" Now Playing Arizona Mom Faces Two Charges of Homicide For Drowning Twins Now Playing Prosecutor: Mom Killed Boys to Keep Family to Just Self, Daughter, Husband Now Playing Trial of James Holmes Enters Closing Phase, Movie Theater Shooter Claims Insanity TRENDING Now Playing Meet the winner of TODAY's Next Big Thing competition Now Playing Watch this dad wrestle his tot to a real wrestling audio track Now Playing Are you ready for the 'pooch selfie?' Now Playing Slow, fast, picky? What your eating style says about you Most Watched Now Playing Sponsored Content Massive flooding pounds the Southeast Now Playing Sponsored Content Coast Guard looking for cargo ship that disappeared during Hurricane Joaquin Now Playing Sponsored Content TODAY's Trending: Woman vs. bear vs. kayak Now Playing Sponsored Content Kendra Hatcher murder: Suspected gunman arrested, warrant issued for 'planner' Now Playing Sponsored Content Oregon shooting gunman wrote hate-filled document found at scene Now Playing Sponsored Content Shooting survivor's brother: My sister asked doctor for bullet he removed Now Playing Sponsored Content Jenna's back! She says baby Poppy has 'completed our family'