TV exposure time in younger crowds has no cognitive effect; may provoke asthma

March 11, 2009

The results are in: youngster who watch TV before age 2 don't appear to have an edge in cognitive development by age 3, research shows.

The results are in: youngsters who watch TV before age 2 don't appear to have an edge in cognitive development by age 3, research shows. But the debate over whether young children should even watch television isn't likely to go away anytime soon.

The prospective cohort study found that, after controlling for criteria connected to a child's cognitive development, when children were exposed to specified amounts of time watching television, there was no apparent effect on how they scored on language and visual motor skills assessments. Lead author Marie Evans Schmidt, PhD, and colleagues reported their findings in the March issue of Pediatrics.

This latest study does not warrant a re-assessment of recommendations issued in 1999 from the American Academy of Pediatrics, which encouraged pediatricians to advise against television or other screen media viewing by children younger than 2.

In measuring media exposure for the study, researchers queried 872 mothers of children (age

In another television-centric study, findings showed that young children who are exposed to more than 2 hours of television daily have greater risk of asthma as they get older, compared to children with less exposure.

Three-year-olds who watched more than 2 hours daily of TV nearly doubled their chances of asthma by the time they turned 11, compared with those who watched less. The findings of this prospective longitudinal cohort study, reported by Andrea Sherriff, PhD, and her research team, were published in Thorax.

The goal of the study was to correlate duration of TV watched and sedentary behavior, which may effect changes in airway responsiveness. The study did not look at what children were viewing.

Data from 3,065 children tracked from birth to age 11 ½ was used as part of the Avon Longitudinal Study of Parents and Children. All participants in this study were not wheezing until they were at least 3 ½.Findings showed that 28.3% of children watched less than one hour, 46.4% watched one to two hours, and 22.6% watched more than two hours. By 11 ½ years, 6% of children had asthma; prevalence rose according to amount of TV watched.

The study was funded by a grant from the UK Medical Research Council.