TV watching can influence young viewers' personalities for better or worse, two new studies suggest. New Zealand researchers who monitored 1,037 people there from childhood until early adulthood link heavy viewing to antisocial behavior and even crime. Every extra hour of weeknight TV watching when young increased by 30 percent the risk of a criminal conviction by age 26, they write.

In a one-year U.S. study, University of Washington researchers split 565 Seattle-area families with children ages 3 to 5 into two groups. One set of children could watch television as they usually did, while the other group was steered toward programs that feature nonviolent conflict resolution, cooperative problem solving, manners and empathy. Such shows include "Dora the Explorer," "Sesame Street," "My Friend Rabbit," "Wonder Pets!" and "Super Why." Both groups of children were evaluated later for social skills. The second bunch showed "significant improvements" by displaying less aggression and selfishness.

Rather than advising parents to limit daily viewing to two hours or less, some pediatricians (children's doctors) now say parents should focus on the type of programs. Youngsters should be steered toward educational or socially positive shows instead of those with violence and aggression. "If the screens are going to be on, let's concentrate on the content and how we can make it work for children," explains Dr. Claire McCarthy of Boston Children's Hospital.

Professor says: "It’s not just about turning off the TV. It’s about changing the channel." – Dr. Dimitri Christakis of the University of Washington, lead author of the Seattle study

Doctor says: "With our society of smartphones and YouTube and video streaming, screen time is becoming more a part of daily life, not less." -- Dr. Claire McCarthy, Boston Children's Hospital

Crime connection: "Young adults who had spent more time watching television during childhood and adolescence were significantly more likely to have a criminal conviction, a diagnosis of antisocial personality disorder and more aggressive personality traits compared with those who viewed less television." -- Lindsay Robertson, public health researcher and lead author of New Zealand study