Attention-deficit/hyperactivity disorder (ADHD) is the most common behavioral disorder in children, affecting as many as two million American children. Children with ADHD are easily distracted, get bored quickly, rarely sit still, and often neglect to think before they act. These characteristics can be a serious detriment to a child’s home and school life.

What causes ADHD? Researchers don’t know for sure. Studies have shown that ADHD is strongly related to genetics, but few studies have investigated whether environment plays a pivotal role in the development of the condition.

Some researchers believe that overstimulation of the brain through television viewing during early childhood may shorten children’s attention spans. A new study in the April 2004 issue of Pediatrics found that hours of television viewed daily at ages one and three was associated with attentional problems at age seven.

About the Study

This study included over 2,500 children from the National Longitudinal Survey of Youth, a biannual survey of a group of nationally representative children.

When the children were one and three years old, their mothers reported the average number of hours the children watched television per day. When the children reached age seven, the researchers used questionnaires to assess the children’s attention span. The questionnaires asked whether the child has difficulty concentrating, is easily confused, is impulsive, is overly obsessive about things, or is restless. Children whose scores exceeded a pre-determined threshold were classified as having attentional problems. This does not mean, however, that they were necessarily diagnosed with ADHD.

The researchers included other information in their analysis that might affect a child’s attention span, including home environment, maternal depression , mental stimulation, and emotional support.

The Findings

The children watched an average of 2.2 and 3.6 hours of television per day at ages one and three, respectively. At age seven, ten percent of the children surveyed had attentional problems.

The number of television hours the children watched per day at both ages one and three was significantly associated with attentional problems at age seven.

Although the findings from this study are intriguing, it is important to keep the following limitations in mind:

  • This study did not diagnose children with ADHD, but used a screening questionnaire to identify children with attentional problems. Though this questionnaire is thought to be valid, the diagnosis of ADHD would have been more reliable.
  • The children’s parents reported hours of television viewed. There is a chance parents underreported their children’s television use, which would have led to an underestimation of the effects of television on attentional problems.
  • These findings do not necessarily mean that television viewing caused attentional problems, just that they are somehow related.
  • Researchers did not distinguish between types of television viewing. Educational television, for instance, may have positive effects on attention.

How Does This Affect You?

These findings indicate that time spent watching television in early childhood may be associated with attentional problems later on. During the first few years of life, the brain develops rapidly. Mental stimulation during these formative years can have an influence on the way a child’s brain develops.

It makes sense that television, with its rapidly changing images and events, may overstimulate a child’s brain and affect brain development. For this reason, the American Academy of Pediatrics (AAP) does not recommend television for children age two or younger. For older children, the AAP recommends no more than 1-2 hours per day of educational, nonviolent television programming.

In a time when we have access to dozens of television programs at any one time, it is important to set limits on the type and amount of television our children view. For optimal development, it is important that children—especially young children—have plenty of positive interaction with other children and adults. Television viewing should never be used as a substitute for playing, reading, socializing, and participating in hobbies and sports.