Many parents limit screen time for their infants, and a few ban it altogether.

But do they pay attention to what the baby sees when it's the grownups' turn to watch TV?

The American Academy of Pediatrics raised the issue of "secondhand TV" on Tuesday, when it issued updated guidance on media use for children under age 2. The academy repeated its original advice from 1999 -- that infants shouldn't watch any television, even shows branded educational -- and addressed the issue of background media for the first time.

Although infants might not understand adult programming, they'll still gaze every 20 seconds or so at a television screen and turn their attention from whatever constructive or independent play they might otherwise pursue, said Dr. Ari Brown, a Texas pediatrician who was the lead author of the policy.

Parents also are distracted by the shows they watch, meaning they spend less time with their infants and give them less attention and fewer words to mimic for language development, she said.

"When the TV is on, the parent is talking less," Brown said. "There is some scientific evidence that shows that the less talk time a child has, the poorer their language development is."

Jerry Bower, a father from Farmington, said he has no interest in putting his 14-month-old daughter in front of a TV. He and his wife both work outside the home, so they only have 90 minutes with their daughter between picking her up from day care and putting her to bed. Bower can see how TV distracts, though. On the rare occasions when his daughter has stayed up after his favorite show started, he has stopped playing with her and focused on the show.

"My wife has called me out on that," he said.

Conflicted parents

The new academy recommendation toughens up some of the most-ignored medical guidance in the nation. An estimated 90 percent of parents allow their children younger than 2 to watch TV. On average, these children watch one to two hours of video programs per day.

Institutions have taken note, though. The New Horizon chain of day care facilities in the Twin Cities has banned televisions in infant and toddler rooms since 2005.

Dr. Harsohena Kaur of Fairview's Oxboro Clinic in Bloomington is a true believer in limiting screen time; her children are 11 and 9 and still don't watch anything at home other than movies on TV.

But when it comes to advising other parents, the pediatrician finds it challenging.

"I realize [television] is a very effective baby sitter when parents are running around the house and trying to get things done," she said. "It's really easy to have their children sit there [in front of a show] and know they'll stay there."

Language, sleep, play

Nicole Peterson of Lakeville said she doesn't ever use the TV as a babysitter. Her 3-year-old daughter and 11-month-old son stay with her in the kitchen when she cooks.

Her daughter is allowed to watch brief, age-appropriate shows such as "Dora the Explorer." And while her son is often in the same room -- theoretically gaining secondhand exposure -- Peterson said she or her husband is always playing with him.

"We'll allow our older daughter to kind of zone out and have her TV time," Peterson said, "but then one of us is playing with the little one."

While the recommendation against all TV time for infants isn't new, Brown said it now reflects stronger research than it did in 1999. More than 50 studies have examined the impact of screen time on this age group. They have shown that TV time is associated with infants who have slower language development, poorer sleep habits and less time spent in constructive play, Brown said.

Brown said children younger than 18 months don't really understand what they are watching, and gain no benefits even from shows that in the past have been advertised as educational. One study found babies laughed equally whether a "Teletubbies" episode was played forward or backward.

"Sesame Street" has proven educational benefits for children older than 2. However, research has found that it can delay development of language skills in infants who watch it, Brown said. "If you don't understand the content, it can't be educational."

Jeremy Olson • 612-673-7744