Ted S. Warren, Associated Press
Elizabeth Jensen, 6, center, and her brother Joe Jensen, 2, left, are given the special afternoon treat of a little TV time, Tuesday, Feb. 12, 2013 at their home in Seattle. A study out this week online in the journal Pediatrics says parents who want kids to behave should monitor and perhaps modify what and how much their children view on TV. In the same issue, a second study links antisocial behavior with excessive TV.

Childhood TV viewing may lead to excessive aggression and perhaps later antisocial behavior, according to a pair of studies just published in the journal Pediatrics.

Because preschool children spend an average of 4.4 hours a day watching television, despite long efforts by groups like the American Academy of Pediatrics to reduce screen time, a University of Washington study suggests parents should focus on what kind of shows children are watching and steer them to educational or peer-friendly programming instead of violent or aggressive fare.

Parents have for years been encouraged to limit children's screen time — including TV, movies, videos, computer games, etc. — to no more than two hours. "The problem is, they are not listening," Dr. Claire McCarthy, a pediatrician at Boston Children's Hospital, wrote in a commentary published along with the two studies. "With our society of smartphones and YouTube and video streaming, screen time is becoming more a part of daily life, not less."

She noted the suggestion is a "variation of the 'if you can't beat 'em, join 'em' idea. If the screens are going to be on, let's concentrate on the content and how we can make it work for children."

The lead researcher, Dr. Dimitri Christakis, director of the Center for Child Health, Behavior and Development at the Seattle Children’s Research Institute, told Torstar News Service that the "principle of you become what you watch" isn't new. But he added that the Washington study had a tighter design than previous research and involved more participants. "A lot of the earlier research was observation on small populations,” he said. “But this is the largest and the most thorough.”

The second study linked antisocial behavior and aggression in early adulthood to television viewing in childhood and adolescence. Researchers from New Zealand looked at 1,037 individuals born in the city of Dunedin, tracking them from birth to age 26. Extra time spent watching TV on weeknights increased the risk of having a criminal conviction by age 26, the researchers said.

They determined that "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." And that held true even after they controlled for other factors, from demographics to intelligence and parental control. That is consistent, they wrote, with a causal association.

The University of Washington study centered around helping parents replace violent shows youngsters might watch with what the researchers called prosocial and educational programming, but the parents in the study were told not to reduce the amount of time children spent watching, just to change the shows. Emphasis was also placed on parents viewing the shows with the children.

"Although television is frequently implicated as a cause of many problems in children, our research indicates that it may also be part of the solution," the researchers wrote.

The year-long study looked at 565 kids, ages 3 to 5, in Seattle. For some of the kids, watching patterns were the same as always, but others were directed toward shows with such features as conflict resolution, teamwork, problem-solving and manners. Then, at six months and again at a year, the researchers looked at each child's social competence.

Seattle Children's Hospital said "prosocial programming encourages children to be kind and to share, and portrays adults as dependable."

Those directed toward the less aggressive, more educational programming showed "significant improvements." According to the Los Angeles Times report on the study, the biggest improvement was seen in boys hailing from low-income homes.

The newspaper noted some limitations to the studies. For instance, the researchers from New Zealand said that it was possible that antisocial behavior led to more TV viewing and not vice versa. And in the Seattle study, researchers said that while parents were not told the purpose of the study, they may have modified their behavior, which could bias the results.

Both sets of researchers said more study is needed.

The children's hospital website noted some things that parents can do to improve the results of childhood screen time. Among them, it suggested keeping a "media diary" to be sure you know what TV shows and movies a child watches, choose less violent and more prosocial content, and watch programming with the kids.

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