Looks like grandma had it right: Too much TV really is bad for you.
It’s possible that TV is making us smarter in some ways because it’s so much more complicated and engaging than it used to be, as contrarians like Steven Johnson have suggested. (Though shows like Real Housewives and Honey Boo Boo must be dumbing down the average.) But a new study from New Zealand suggests too much TV when we’re kids leads to increases in anti-social behavior and even criminality—a smarter generation of miscreants, perhaps, with a knack for following complex plots.
For the study, researchers from the University of Otago, in New Zealand, gathered data from around 1,000 children born in 1972 and 1973. Every two years, between the ages of five and 15, the researchers asked those children how much television they watched.
What they found was striking: By early adulthood, the risk of a subject’s having some kind of criminal conviction increased by around 30 percent with each extra hour of TV watched on an average weeknight. The results were published online this week in the American academic journal, Pediatrics.
At first glance, it seems obvious that several outside influences could interfere with a study like this. Could aggressive, anti-social children, for instance, simply be more prone to watching more TV? But researchers say they have controlled for confounding factors like aggressive or antisocial behavior in early childhood, socio-economic status, or parenting factors.
There are limits to the kinds of definitive cause-and-effect conclusions one can draw from any observational study, they acknowledge. Excessive TV-watching won’t definitely lead to anti-social behavior every time. But the controls and longitudinal nature of the study suggest it isn’t happening the other way around.
“While we're not saying that television causes all antisocial behavior, our findings do suggest that reducing TV viewing could go some way towards reducing rates of antisocial behavior in society,” said Bob Hancox an associate professor at Otago and one of the study’s co-authors.
As noted in an article for the Los Angeles Times, the study comes at a time when another study out of the University of Washington, also in Pediatrics, suggests that the kind of television children are watching has a significant bearing on its effects, not just the amount. For the study, researchers instructed parents on how to make their children’s television more educational and pro-social than the usual, often violent stuff. They did not ask them to reduce the number of hours their kids watched TV.
As the LA Times writes it:
Both groups of children were evaluated for their social competence after six months and after 12 months.
The intervention group showed “significant improvements” in social competence testing scores after six months, wrote Dr. Dimitri Christakis, lead author and pediatrics professor. Low-income boys appeared to benefit the most, authors said.
“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,” authors wrote.
For busy parents, changing the content not the quantity could be a good compromise, the latter study implies. “It is a variation on the ‘if you can't beat ‘em join ‘em’ idea,” writes Claire McCarthy, a pediatrician at Boston Children's Hospital, in a commentary accompanying the findings. “If the screens are going to be on, let's concentrate on the content, and how we can make it work for children.”
That the New Zealand study didn’t discriminate between educational and violent TV, it stands to reason that the amount of violent TV in their children’s media diets may have had a direct bearing that parents could mitigate with a little effort.
Still, interpreted another way, the New Zealand’s study indicates that excessive amounts of any kind of TV can have negative consequences. Taken together, the studies suggest that careful parents would do well to make sure their children watch less TV that’s better.