The digital divide used to separate rich from poor; now it separates parents from their children. Whether it's infants watching the new 24-hour "Baby's First TV" channel, or teenagers instant messaging while they watch last night's "Daily Show" on their iPods, television is an enormous presence in the lives of kids today. The average American child spends three to five hours a day watching it. And they start their viewing careers much earlier than ever before: In 1961, the average child began to watch television at age 3; today it is 9 months.
Yet, for all the television kids are watching, much of what parents think they know about television's impact on their children is wrong. For instance, in the early 1970s, it was common knowledge that television was bad for your eyes: My own parents were convinced that my bad eyesight was the result of sitting too close to the screen, and they therefore made me stay at least six feet from it. Today, most people know that television viewing does not cause vision problems, but a host of new myths have emerged, still ripe for debunking:
1. TV makes kids dumb. Actually, high-quality TV shows such as "Sesame Street" and "Blue's Clues" improve children's cognitive abilities. Study after study has shown that children 3 to 5 years old who watch "Sesame Street" for an hour a day are better able to recognize numbers, letters and shapes than those who don't. When 500 kids who had participated in some of those studies were followed up as teenagers, those who had watched educational programs as preschoolers had higher grades, were reading more books, placed more value on achievement and were more creative than those who had not.
2. TV makes kids violent. The real story is more complicated. In 1994, researchers reviewed hundreds of studies involving thousands of children and concluded that there was clear evidence that watching violence on TV makes children more aggressive. Similarly, preteens and teenagers exposed to sexual content on television are more much more likely to engage in the kinds of activities they see on the screen.
But a study of more than 5,000 children also found that "pro-social" programs (think "Mr. Rogers' Neighborhood") make children kinder and more tolerant. In fact, the linkage between good behavior and watching good programming is as strong as the link between bad behavior and bad programming. The problem is that kids are increasingly watching shows with violence and sex instead of programming that is appropriate for their age.
3. Educational videos make infants smarter. The names such as Baby Einstein and Brainy Baby suggest one thing, but the data suggest otherwise. According to a 2005 report by the Kaiser Family Foundation, no program targeting children younger than 2 has demonstrated any educational benefit.
Evidence from studies my colleagues and I have done suggests that early viewing (under age 3) may be harmful to children's cognitive development. We found that children who watch TV before age 3 score worse on tests of letter and number recognition upon entering school than those who do not. And for each hour of television a child watches on average per day before age 3, the chances that child will have attention problems at age 7 increase by 10 percent. A 2005 University of Pennsylvania study found that even watching "Sesame Street" before age 3 delayed a child's ability to develop language skills.
4. Sitting around watching television instead of playing outside makes kids overweight. In fact, being a couch potato is not what causes obesity. Kids sit around to read, too, but no one suggests that reading causes obesity. A 1999 Stanford University experiment found that when elementary school children watched less television, they did lose excess weight; however, reducing their television time did not make them more active.
What that suggests is that television-watching itself unlike other sedentary activities such as reading, block-building or working on art projects encourages overeating. Snacking in front of the tube is a widespread habit (for kids as well as adults) and the barrage of junk food advertisements only heightens that temptation. About 70 percent of the ads children see on television are for food products, and virtually none of them are for healthy choices. A 2005 Harvard University study found that, on average, children eat about 170 more calories per day for each hour of television they watch, and all of those calories are derived from foods commonly advertised in television commercials.
5. Television helps kids get to sleep. The opposite is true. In a 2005 study of more than 2,000 children, my colleagues and I found that the more television children watch, the more likely they are to have irregular sleep and nap patterns. Allowing kids to watch television because they can't sleep is part of the problem, not the solution.
6. Kids watch too much television. Actually, the bigger problem is what they watch and how they watch it. In what some consider the halcyon days of television, families used to gather around a single centrally located set and watched high-quality, family-centered programming together.Nowadays, the typical U.S. household has multiple television sets; family members (including young children) sit alone and watch programs that too often are violent and sexualized. When parents watch with their children, the value of the best television programs is enhanced and the harm of negative programming can be curtailed.
Dimitri A. Christakis, a pediatrician and researcher at Children's Hospital in Seattle, is coauthor of "The Elephant in the Living Room: Make Television Work for Your Kids" (Rodale). Author e-mail: email@example.com