Only one in 20 American children responded to full recommendations about time spent in front of a screen, physical activity and sleep – ScienceDaily

Taken individually, a limited screen time and improved sleep have been associated with the strongest links with the enhancement of cognition, while physical activity may be more important for physical health.

However, only one in 20 American children 8 to 11 years old meets the three recommendations of the Canadian 24-Hour Travel Guidelines to ensure good cognitive development – 9 to 11 hours of sleep, less than two hours of time spent a screen, and at least one hour of physical activity each day.

The study found that American children spent an average of 3.6 hours per day on the screen time.

The authors say their findings indicate that adherence to guidelines during childhood and adolescence, especially for screening, is important for cognitive development.

"Daily behaviors and activities contribute to brain and cognitive development in children, and physical activity, sedentary behaviors, and sleep can affect cognition independently and collectively," says Dr. Jeremy Walsh, Research Institute of CHEO, Ottawa, Canada. "The data suggest that good sleep and physical activity are associated with improved school performance, while physical activity is also related to improved reaction time, attention, memory, and physical activity. The link between sedentary behaviors is in the early stages and it seems to vary depending on the types of activity on screen.

In the study, data were analyzed from 4,520 children at 20 sites across the United States. Children and parents completed questionnaires and measurements at the beginning of the test to estimate physical activity, sleep and time spent in front of the child 's screen. The children also completed a cognition test that assessed language skills, episodic memory, executive function, attention, working memory, and processing speed. The study focused on household income, education of parents and children, ethnicity, pubertal development, body mass index and the eventual presence of children. traumatic brain injury in the child.

Almost one in three children (29% – 1,330 / 4,520) did not meet any of the guidelines, 41% (1,845 / 4,520) only met one, 25% (1,129 / 4) 520), two (5%) (216/4 520) the three recommendations.

Half of the children responded to the sleep recommendation (51%, 2,303/4,520), 37% (1,655 / 4,520) responded to the screening recommendations, and 18% (793/4,520) met the recommendations of the recommendations. 39, physical activity.

The more individual children had individual recommendations, the better their cognition. In addition, only recommendations for screen time or recommendations for screen time and sleep were most strongly associated with cognitive development.

Although there is substantial evidence of the association between physical activity and cognitive development, in this study responding to the recommendation of physical activity alone has shown no association with cognition. The authors note that this discovery is surprising and may suggest that the measure used may not have been sufficiently accurate. They note that physical activity remains the most important behavior for physical health outcomes, and nothing indicates that it negatively affects cognition.

Dr. Walsh concludes, "We found that more than two hours of screen time was associated with lower cognitive development. More research on the links between screen time and cognition is needed. According to our findings, pediatricians, parents, educators and policy makers should promote limiting screen time and prioritize healthy sleep patterns throughout childhood and adolescence.

The authors note some limitations, including that their study is observational and therefore can not establish the underlying causes or direction of the association. Data is also self-reported and may be biased. The questionnaires were only used at the beginning of the study and therefore do not allow to follow behavior changes over time. Future study cycles will need to be analyzed to understand trends over time.

In a related commentary, Dr. Eduardo Esteban Bustamante of the University of Illinois, USA, states: "Through a stress-adaptive lens, Walsh and his colleagues can cycle the stress recovery needed to growth in children who do not respond to the recommendation: every minute spent on screens necessarily shifts a minute of sleep or cognitively stimulating activities. It is tempting to find that cognitively challenging screening activities can be beneficial for cognition, but if given the choice, most children consistently and predictably choose more challenging screening activities.