Some experts believe that technology has a role in the rising rates of ADHD ; but whether it causes the disorder is still being debated.
By Lesley AldermanMedically reviewed by Kevin O. Hwang, MD, MPH
Kids love screens. Put a child in front of SpongeBob or Pokémon or a Super Mario Brothers video game and within minutes he will be totally absorbed by the action in front of him — so absorbed that you may have to cry “Fire!” or “Candy!” to get his attention. The irony, though, is that while TV shows, movies, and video games can capture a child’s attention for hours, they may be eroding a child’s ability to focus attentively when he is back in the ho-hum, real-time world.
Could our media-saturated society be contributing to or aggravating attention problems, like ADHD (attention-deficit hyperactivity disorder), among children?
There is clearly more ADHD and more media in modern life. The amount of time kids spend watching, or interacting with, screens has risen dramatically in recent years. On average, kids from 8- to 18 spend 7 hours and 38 minutes a day using entertainment media, according to a Kaiser Family Foundation report of January 2010. That’s one hour and 17 minutes, or nearly 20 percent, more than they spent on such media five years ago.
Meanwhile, according to the Centers for Disease Control and Prevention, 7 percent of children age 3 to 17 have been diagnosed with ADHD — about 4.5 million kids. Diagnoses of ADHD have been on the rise for more than a decade, increasing by 3 percent a year from 1997 to 2006.
How Much Is Technology to Blame for ADHD?
No one knows for sure to what degree these rising rates can be ascribed to technology, but some believe that combined media are having a noticeable effect. A recent study assessed the viewing habits of 1,323 children in third, fourth, and fifth grades over 13 months and found that children who spent more than two hours a day in front of a screen, either playing video games or watching TV, were 1.6 to 2.1 times more likely to have attention problems.
The study, which was published in the August issue of Pediatrics, also found that exposure to “screen media” was associated with attention problems in a sample of 210 college students. “This study contributes to a growing body of research that shows media may have an effect on attention,” says Dimitri Christakis, MD, MPH, director of the Child Health Institute at the University of Washington in Seattle.
Dr. Christakis, who has spent the last decade studying how entertainment affects children’s mental processing, believes that overstimulation from media may be a possible cause of ADHD. In one study, Christakis found that kids under the age of 5 who watched two hours of TV a day were 20 percent more likely than kids who watched no TV to have attention problems at school age. Christakis concedes, however, that the science in this area is still emerging. “If I thought I knew the answer definitively, as to what was causing ADHD," he notes, "I would not still be doing research."
The American Academy of Pediatrics is persuaded enough of the detrimental effect that it recommends that children spend no more than one to two hours a day interacting with screen-based media, such as TV and video games. And the recommendation for children under the age of two is no TV at all. The brain is a highly adaptive and sensitive organ, so it makes intuitive sense that something like fast-paced video games could alter the way it reacts to stimuli.
“In the last 50 years we have created platforms in which we present things in surreal time,” says Christakis, who is also the author of The Elephant in the Living Room: Make Television Work for Your Kids. “When you condition the mind to become accustomed to high levels of input, there’s a chance that reality can just become boring.”
ADHD is a neurobehavioral developmental disorder. People with ADHD have difficulty staying focused on one task and controlling their impulses and are often fidgety or hyperactive. They have a hard time synthesizing facts, so they tend to have trouble seeing the forest for the trees. Brain scans show that people with the disorder actually work harder than average to absorb what must feel like a barrage of information. Symptoms usually appear between the ages of 3 and 6. Poor attention is one of the most notorious signs of ADHD, but it is really part of a constellation of symptoms.
While technology does seem to have some effect on attention span, many researchers balk at saying outright that technology and media cause ADHD. “Technology does not cause ADHD,” says Jacquelyn Gamino, PhD, head of ADHD research at the University of Texas Dallas School of Behavioral and Brain Sciences.
While the research showing that kids who watch TV have poorer attention spans later in life is compelling, it’s difficult to establish that TV or video games were responsible for those problems. “Which caused which?” Dr. Gamino asks. Perhaps parents of restless kids are more likely to sit them in front of the TV to calm them down. Or perhaps children with ADHD gravitate toward over-stimulating media as a way of self-medicating. After all, many medications for ADHD are actually stimulants. The Web site of the National Institute of Mental Health does not list technology and media as probable causes of ADHD.
Researchers who dismiss the technology-ADHD link point to the fact that genetics plays a large role in the disorder. Kids with ADHD are more likely to have parents and siblings with the disorder. Scientists are finding that kids with ADHD have brains that are different from those of kids without the disorder. “People with ADHD have, by chance, ended up with combinations of genes that lower attention capacity,” says Chandan Vaidya, PhD, a cognitive neuroscientist and associate professor of psychology at Georgetown University. These combinations of genes influence neurotransmitters like dopamine and norepinephrine that regulate attention. An NIMH study published in the Archives of General Psychiatry in 2007 found that kids with ADHD who carry a particular version of the dopamine receptor D4 (DRD4) gene have thinner brain tissue in the areas of the brain associated with attention. However, the brain tissue and ADHD symptoms tended to improve as the children grew older.
Environmental toxins may also contribute to ADHD. For example, prenatal exposure to cigarette smoke and alcohol, and early childhood exposure to lead, may increase a child’s risk for developing the disorder. A recent analysis of data from the 2001-2004 National Health and Nutrition Examination Survey (NHANES) found that children who were exposed to tobacco in utero were 2.4 times more likely to have ADHD than children who were not. The same study, which was conducted at Cincinnati Children's Hospital Medical Center, found that kids exposed during early childhood to lead, which is sometimes found in plumbing fixtures or paint in old buildings were 2.3 times more likely to have ADHD than those who were not exposed.
Pesticides are another possible culprit. Another NHANES analysis conducted at the Harvard School of Public Health found that children whose urine contained traces of organophosphate pesticides were more likely to be diagnosed with ADHD than other children. The more of the metabolites that were present, the more likely the child was to have ADHD.
It seems as if all sorts of bad things are being linked to ADHD. Rresearchers found that a Western fast-food diet (which some might consider toxic) full of highly processed, fried and refined foods was associated with a high risk of being diagnosed with the disorder. A "fast-food" diet tends to be higher in total fat, saturated fat, refined sugar and sodium than a diet based on fruits, vegetables, and whole grains. The study, which was conducted in Australia and examined the eating habits of 1,800 adolescents, was published in the Journal of Attention Disorders. But as with the media studies related to attention, it’s difficult to establish a cause-and-effect link. It is possible that kids with attention problems eat more fast food because it requires less attention. Or perhaps a fast-food diet is simply a marker of lower socioeconomic status and parental education levels, which have also been associated with ADHD.
With so many possible causes, what can parents do to limit the chance that their kids will develop the disorder? Some things, like genetics, can’t be controlled. But even if your child does have some of the genetic variants linked to ADHD, it doesn't mean he or she will definitely end up with ADHD. “The environment in which you live can make up for or exacerbate the problem,” Dr. Vaidya notes. Kids with ADHD who are given help with organization and planning, for instance, tend to function better in school than kids left to founder on their own.
It’s probably wise to limit your child’s time with screen media. While these media may not cause ADHD, they could very likely exacerbate a problem that’s already there — or simply lead to poorer attention overall. Researchers are still not sure what kind of media content, exactly, affects attention. Some video games are even considered useful, because they improve hand-eye coordination and critical thinking. To be on the safe side, try to limit young children’s exposure to fast-paced television shows and video games to less than two hours a day.
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