Researchers at Harvard Medical School and the Center on Media and Child Health reported on Monday that television has neither a positive nor negative effect on the cognitive development of young children.

Researchers monitored 872 children from birth to three years of age in terms of how many hours they spent in front of a television screen. The findings revealed that children who watched educational programs were no more adept in vocabulary or visual and motor ability tests than those who did not.

“Educational programs are a way of making parents not feel guilty with parking their kid in front of an electronic baby sitter,” said Michael O. Rich, the director of CMCH and associate professor of pediatrics at the Medical School.

According to Rich, only six percent of parents are aware that children under the age of two should not be in front of an electronic screen.

Several of the researchers expressed hope that further research would investigate the effects of television viewing in children older then three years as well as the effects of content matter.

Previous studies have found that although overall television viewing had no effect on children, watching baby videos specifically had a negative impact on vocabulary.

“Parents must be aware that although the study does not show evidence of harm, there are some indications that TV viewing at high levels can put children at risk of obesity, sleep problems, and attention problems,” said Marie E. Schmidt, the study’s lead author.

Schmidt, a developmental psychologist and instructor of pediatrics at the Medical School and a research associate at CMCH, added that parents should be encouraged to limit their children’s television viewing.

The interface between media and child health is a relatively new area of research, and Elsie M. Taveras, an assistant professor at the Medical School, said there is still more research to be done.

“Parents need to be educated about what is the scientific evidence for ‘educational benefits’ of TV viewing,” Taveras said.

Schmidt added that one study is not enough to reach a conclusion but that the amount of publicity the study has received is evidence that parents are “hungry for this information.”