What kids watch — and not just how much — matters when it comes to television viewing, according to new research that finds that preschoolers who watch fast-paced shows have far more trouble concentrating than other children.

The research, published Monday in the journal Pediatrics, finds that kids who watched just nine minutes of a “very popular fantastical cartoon about an animated sponge that lives under the sea” (that sounds like code for SpongeBob SquarePants) were “significantly impaired” in tests of executive function — essentially a person’s ability to stay on task and not get distracted — compared with children who were assigned either to watch an educational cartoon (in this case, Caillou) or to draw.

The University of Virginia study was fairly small — it tracked just 60 4-year-olds — but it’s notable because the decline found in children’s focus was immediate, in contrast to other research that has found long-term attention deficits. “If television has long-term effects on executive function, then one might see small short-term effects; even adults report feeling less alert immediately after watching television,” wrote the authors.

Right after viewing either cartoon clip or drawing for nine minutes, the kids were given a variety of tests of executive function: solving problems, delaying gratification, following rules and remembering other information. The problem-solving test asked children to move disks from one peg to another. The gratification test measured how long the children were able to resist eating snacks.

The kids who watched the fast-paced cartoon performed worse across the board than the other two groups. While 15% of SpongeBob viewers passed the problem-solving task, for instance, 35% of those who watched the educational cartoon did, compared with 70% of the kids who spent the time drawing. After viewing the fast-paced cartoon, kids also showed less ability to delay gratification and to follow rules than the other groups.

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Why are fast-paced shows more detrimental than slower-paced programs? They affect different parts of the brain, posit the researchers, and “the effort to encode rapidly presented events could tax children’s executive resources.” For the purposes of the study, the fast-paced show had complete scene changes every 11 seconds compared with 34 seconds for the slower-paced program.

“If these findings are borne out, it means that content is as important as quantity,” says Dimitri Christakis, director of the Center for Child Health, Behavior and Development at Seattle Children’s Research Institute and author of an accompanying commentary in Pediatrics. “It’s not just about turning off your TV but about changing the channel. What kids watch is as important as how much they watch.”

Executive function is key to learning. It’s also what helps people maintain focus, plan, organize and control inappropriate behaviors.

But aren’t there also some benefits to being able to distract your attention from one task to another? In his commentary, Christakis considers that point of view:

Simply stated, so what if too much of a fast-paced cartoon makes children highly distractible? Distractibility is all relative. Executives of the future (if not the present) will not focus on a single task but on many concurrently while updating their Facebook status. In the 21st century, distractibility is not a liability, some argue, but an asset. It is hard for me to see (let alone acknowledge) that this is the case. Focus seems too central to wise decision-making.

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Many parents lay down the law when it comes to how much programming their children can indulge in, but far fewer legislate what they can watch, says Christakis. If your child watches two hours of television each day, educational content is preferable to fast-paced cartoons. “Too many children watch too much TV,” says Christakis. “But it’s at least as important to figure out what they should watch. SpongeBob, for what it’s worth, isn’t even supposed to be viewed by kids between the ages of 3 to 5. That alone is a guide for parents: watch age-appropriate content.”

Apparently, lots of parents are having their own problems with executive function: despite its age-viewing recommendations, SpongeBob SquarePants is the most-watched TV show among kids between the ages of 2 to 11.