Despite what we have been led to imagine, the timing of evening screen use, quite than the activity itself, negatively impacts youth sleep, a University of Otago study has found.
Current sleep guidelines recommend no screen use within the hour or two before bed. Nonetheless, the researchers found screen time within the two hours before bed had little impact on youth sleep, it was screen time once in bed that caused problems.
Lead writer Dr Bradley Brosnan, of the Edgar Diabetes and Obesity Research Centre, says screen time is a mainstay in adolescents’ bedtime routines, and sleep guidelines have to be revaluated to higher reflect modern life.
Published in JAMA Pediatrics, the study had 85 adolescents aged 11 to 14 years wear a body camera on their chest from three hours before bed until they got into bed, over the course of 1 week.
Together with the body camera capturing when, what and the way they used their screens, a second infrared camera was placed of their bedrooms to capture their screen time while in bed. Additionally they wore an actigraph, a watch-sized device which measures sleep.
“It quickly became obvious that adolescents spend quite a lot of their screen time while in bed,” Dr Brosnan says.
The researchers found 99 per cent of participants used screens within the two hours before bed, greater than half used screens once in bed, and a 3rd used them after first trying to fall asleep for the night.
“Our most interesting findings were that this screen time before they got into bed had little impact on sleep that night.
“Nonetheless, screen time once in bed did impair their sleep — it stopped them from going to sleep for about half an hour, and reduced the quantity of sleep they got that night.”
This was particularly true for more interactive screen activities like gaming and multitasking — when a couple of device is used at the identical time, akin to watching a movie on Netflix on a laptop while playing Xbox on a gaming device.
“Every additional 10 minutes of this kind of screen time reduced the quantity of sleep they got that night by almost the identical amount.
“Our findings suggest that the impact of screen time on sleep is primarily through time displacement delaying sleep onset quite than any direct effects of blue light or interactive engagement as we didn’t find associations with sleep latency and wakefulness in the course of the sleep period.”
Dr Brosnan says a ‘easy’ sleep guideline — in theory but not necessarily reality — can be for devices to be kept out of the bedroom, allowing teenagers to make use of their devices before bed, but not in bed.
“We want to revisit sleep guidelines, so that they fit the world we live in, and really make sense — the present ones aren’t achievable or appropriate for a way we live.”
