September 27, 2018

expert reaction to study on sleep, exercise, recreational screen time use and cognition in children

Researchers, publishing in The Lancet Child & Adolescent Health, report that over two hours of recreational screen time a day was associated with poorer cognitive function in children.

Dr Kirsten Corder, Senior Investigator Scientist, MRC Epidemiology Unit, University of Cambridge, said:

“This new research adds to existing evidence, and supports concerns about screen time and potential negative links with cognitive development in children. Although this study is from the USA, it is likely that these results will be somewhat relevant to the British context.

“Importantly, this study confirms that physical activity is not harmful to cognition and emphasises its importance for physical health. The guidelines used here broadly align with British recommendations, where an average of an hour a day of activity is suggested for children.

“Recreational screen time and physical activity were reported by 8-11 year-old children and it is likely that many children may have struggled to answer the questions accurately. Although different types of screen time were measured (such as social media and watching television) separate results for those behaviours are not reported. The questionnaire-style measurements currently used in many large studies often do not provide enough precision to find important associations with these kinds of behaviours. We need to develop much more accurate ways to assess screen time in detail.

“Less than 2 hours of daily screen time was associated with higher global cognition, but other factors included (such as ethnicity and school grade) displayed stronger associations. Incorporating screen time into programmes to improve cognition will need to consider many other factors.

“As these factors were only measured at one time point, the results cannot prove a causal relationship, but do align with other studies that suggest that reducing screen time may be worth incorporating in programmes aiming to improve cognition. These results will hopefully stimulate further research using techniques that allow researchers to explore how multiple behaviours may interplay to benefit cognition and health.”

All our previous output on this subject can be seen at this weblink: http://www.sciencemediacentre.org/tag/screentime/

Declared interests

None  received.