Staring into the darkness

Washington: Night-time use of phones, tablets, and laptops is consistently associated with poor sleep quality, insufficient sleep, and poor perceived quality of life, a recent study has suggested.

According to the research, pre-teens who use a mobile phone or watch TV in the dark an hour before bed are at risk of not getting enough sleep compared to those who use these devices in a lit room or do not use them at all before bedtime.

The study found that insufficient sleep has also been shown to be associated with impaired immune responses, depression, anxiety and obesity in children and adolescents.

Data was collected from 6,616 adolescents aged between 11 and 12 and more than 70 per cent reported using at least one screen based device within one hour of their bedtime. They were asked to self-report a range of factors including their device use in both lit and darkened rooms, their weekday and weekend bedtimes, how difficult they found it to go to sleep and their wake up times.

The results showed that those who used a phone or watched television in a room with a light on were 31 per cent more likely to get less sleep than those who didn't use a screen. The likelihood increased to 147 per cent if the same activity took place in the dark.

It has been reported that globally, 90 per cent of adolescents are not sleeping the recommended nine to 11 hours per night, which has coincided with an increase in the use of screen-based media devices. Findings of the study were published in the Journal of Environment International.

Previous studies have shown that sufficient sleep duration and quality are vital in childhood to maintain physical and mental development. Sleep is also crucial for cognitive processes and a lack of sufficient sleep has been directly related to poor academic performance.

"While previous research has shown a link between screen use and the quality and length of young people's sleep, ours is the first study to show how room lighting can further influence this. Our findings are significant not only for parents but also for teachers, health professionals, and adolescents themselves," said Michael Mireku, lead author of the study.