Researchers at the University of Massachusetts said that despite pediatricians' recommendations that there be no screen media exposure for children under age 2, three-quarters of very young children in the United States live in homes where the television is on most of the time.

The study, published in the July/August issue of the journal Child Development, found background TV was found to disrupt the toy play of the children, even when they paid little attention to the TV -- the children played for significantly shorter periods and time spent focused on play was shorter when the TV was on.

Lead author Marie Evans Schmidt, now a research associate at the Center on Media and Child Health at Children's Hospital Boston, looked at 50 children ages 1, 2, and 3.

Each child went to a lab with a parent and was invited to play for an hour with a variety of age-appropriate toys -- half the time with a television on in the room, showing an episode of the adult game show "Jeopardy!" with commercials; the other half-hour, the TV was turned off.