Young girls who spend the  most time multitasking between various digital devices, communicating  online or watching video are the least likely to develop normal social  tendencies, according to the survey of 3,461 American girls aged 8 to 12  who volunteered responses.
The study only included  girls who responded to a survey in Discovery Girls magazine, but results  should apply to boys, too, Clifford Nass, a Stanford professor of  communications who worked on the study, said in a phone interview. Boys'  emotional development is more difficult to analyze because male social  development varies widely and over a longer time period, he said.
"No one had ever looked  at this, which really shocked us," Nass said. "Kids have to learn about  emotion, and the way they do that, really, is by paying attention to  other people. They have to really look them in the eye."
The antidote for this  hyper-digital phenomenon is for children to spend plenty of time  interacting face-to-face with people, the study found. Tweens in the  study who regularly talked in person with friends and family were less  likely to display social problems, according to the findings in the  publication Developmental Psychology.
"If you eschew  face-to-face communication, you don't learn critical things that you  have to learn," Nass said. "You have to learn social skills. You have to  learn about emotion."
The Stanford researchers