Lots of us habitually have the TV on while we're doing other things, like getting dressed or cooking dinner, says Lisa Guernsey, author of Screen Time: How Electronic Media -- From Baby Videos to Educational Software -- Affects Your Young Child. What to do? "If you're not really watching, Turn. It. Off," Guernsey stresses. You might even consider skipping TV altogether when children are around. "Background music would be my choice," Dr. Linebarger says, because there's no distracting visual stimuli.