Life isn't so easy for the poor sponge that lives in a pineapple under the sea.

Back in 2005, SpongeBob attracted controversy when a Christian evangelical group accused the popular cartoon of promoting a gay agenda. Now a new study says watching the bright yellow sponge could negatively affect schoolchildren's minds.

The new study, published online on Monday in the journal Pediatrics, concludes that watching the cartoon had negative effects on 4-year-olds attention spans. In comparison watching a more realistic PBS cartoon did not have negative effects.

The American Academy of Pediatrics said its study found that pre-school children "were significantly impaired in executive function immediately after watching just nine minutes of a popular fast-paced television show relative to after watching educational television or drawing."

The AAP also recommends that children over the age of 2 should only watch no more than one or two hours a day of educational programs and those children under the age of 2 not watch any television at all.

Dr. Dmitri Christakis, a pediatrician at Seattle Children's Hospital urges parents to also monitor what their children watch not just how long they watch television.

"Most parents worry too much about how much TV their children watch and not enough about what they watch," he says. "It's not about turning the TV off. It's about changing the channel."

Researchers from the University of Virginia asked 60 mostly white and middle or upper middle class 4-years olds to participate in the study. The researchers then divided the participants into three groups. One group watched a 9-minute clip of "SpongeBob SquarePants", the second group watched a 9-minute clip of "Caillou" a realistic PBS cartoon and the third didn't watch television and drew pictures for the same amount of time.

The researchers then tested the three groups on their ability to focus on a task. The PBS and non-television watching group did well on the tests, the SpongeBob group scored worse.

The researchers theorized that watching the more rapid pace and fantastic characters of SpongeBob might agitate the preschoolers too much to focus on certain tasks.

"It confirms something that parents have observed for some time," Christakis says of the study. "They put their kids in front of television, particularly fast-paced programming, to quiet them down, but when the TV goes off, the kids are more amped up than they were before."

Nickelodeon spokesman David Bittler questioned the methodology of the study.

"Having 60 non-diverse kids, who are not part of the show's targeted demo, watch nine minutes of programming is questionable methodology and could not possibly provide the basis for any valid findings that parents could trust."

A key issue for Nickelodeon officials: "SpongeBob" is targeted to kids 6-11, but the study focused on 4-year-olds.