Even if we aren’t actively watching TV, most of us leave the set on in the background. But that may have detrimental effects on children in the home, according to a new study published in the journal Pediatrics.
Matthew Lapierre, an assistant professor of communications studies at the University of North Carolina Wilmington, and his colleagues conducted the first study to quantify how much background TV young children are exposed to on an average day. While many previous studies have focused on the effects of direct TV viewing on children’s behavior and development, Lapierre’s was the first to investigate what might be considered “secondhand” TV exposure, defined as any exposure to television that the child is not actually watching.
To the authors’ surprise, in the survey of 1,454 parents with at least one child between the ages of 8 months and 8 years, the scientists found that children were subjected to nearly four hours of background TV a day. “We were all startled by the scale of the exposure in these homes,” says Lapierre, who conducted the research while at the University of Pennsylvania. “We went into the study expecting the rates to be high, but not at the scale we found.”
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The households were recruited by a phone survey group, which enrolled typical American families that represented a broad range of demographic variables, from ethnicity to income and education. Parents answered questionnaires about the activities of one of their children in a 24-hour period, and were asked about whether a television was on during any of these activities. On average, background exposure amounted to 232.3 minutes a day, with exposure being greatest for younger children: infants and toddlers under 24 months logged about 5.5 hours of background TV a day, compared with 2.75 hours a day for the oldest children, aged 6 to 8.
Parental influences played the greatest role in determining how much background TV children experienced. Other factors that increased indirect TV exposure included living in a single-parent family, where children were exposed to more than 5 hours a day, compared with 3.5 hours in multiparent homes; lower household income, with children in the poorest families experiencing 6 hours of background TV a day, compared with 3.5 hours among those whose family income reached above the poverty level; and lower parental education, with children of parents with high school diplomas or less being exposed to more than 5 hours a day, compared with less than 2.5 hours a day for those whose parents had more formal education.
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The data were alarming given that children under age 6 already watch about 80 minutes of television a day directly; these findings suggest that indirect TV exposure is greater than direct watching, and could have equally, or potentially more serious effects on children’s development. Studies have linked excessive TV viewing with obesity in children, while violent and sexually inappropriate programming has been correlated with behavioral and cognitive problems in young viewers. (In contrast, educational programming has been associated with learning and cognitive benefits.)
Lapierre says that his study also hints at difficulties with executive function and self-regulation among kids who are exposed to more background TV, but those findings are still preliminary and will be explored in more detail in additional studies. While his study did not explore the consequences of indirect TV exposure, previous trials suggest that it can affect children’s concentration and behavior in relationships. In one such study, conducted at the University of Massachusetts, scientists observed parents and their toddlers as one group interacted in the presence of a television and the other group interacted without a TV. In the television group, despite the fact that the parents and children were not watching the programming, their interactions were less frequent and the children’s play episodes were shorter.
Parents might not think that young toddlers are processing television content when it’s on in the background, but they may be more distracted by the screen than parents realize. And much of that exposure is not to children-friendly programming, but likely adult content targeted for parents. “The thing we find most concerning is that if a child has a television on in the background, then he is hearing things that are supposed to elicit his attention like loud noises, sound effects and beeps, so even if they aren’t watching directly, they aren’t able to engage in play behaviors or interactions with their full attention and have more meaningful experiences,” says Lapierre.
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What also concerns Lapierre and other child development experts is that despite all the focus on how much television children watch purposefully, they are actually indirectly exposed to far more television than anyone imagined. Further, it’s not surprising that the youngest children are exposed to the most secondhand TV, the authors note, since parents and caregivers likely leave the set on, either as stimulation for themselves or as background noise to combat the loneliness of not being able to converse with another adult. Such indirect exposure is also highest in families with lower educational levels and lower incomes, as the television is more likely to become a substitute for meaningful interactions in these situations.
How can parents help their children reduce their secondhand TV exposure? Removing TVs from children’s bedrooms is an important first step, since it’s easier to turn on sets if they are there. Second, while it seems obvious, simply making sure to turn off the TV if nobody is watching can also steer children’s attention and energy toward other activities, whether it’s a conversation or play. The American Academy of Pediatrics recommends that children under 2 not watch any television at all, in order to protect their cognitive and behavioral development; the current findings suggest that policy may need to include all exposure to TV, whether it involves direct viewing or not.
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Alice Park is a writer at TIME. Find her on Twitter at @aliceparkny. You can also continue the discussion on TIME’s Facebook page and on Twitter at @TIME.