How your mobile phone steals sleep time
Bringing your mobile phone, tablet or computer to bed is a bad idea if you want a good night’s sleep, researchers at UiB have found.

Main content
Whether you read e-mails, check how many Facebook likes you’ve got or just surf the internet randomly at bedtime, this may impair sleep. This according to a sleep study done by researchers at the Faculty of Psychology at the University of Bergen (UiB).
In the study, more than 500 students answered questions about their online media habits at bedtime. More than 90 per cent admitted to web surfing, watching movies or emailing at least once a week just before going to sleep.
“Our sleep study shows a clear connection between web surfing and insomnia, i.e. sleep problems,” says Professor Ståle Pallesen at UiB’s Faculty of Psychology.
Late risers more online
As well as being associated with insomnia, the study showed that use of online media at bedtime seems to influence other aspects of the human sleep pattern. Late risers surfed the web more and watched more movies online than early birds. People with delayed circadian rhythms spent more of their time in bed on social media compared to those with a more advanced circadian rhythm.
Although the researchers spotted a connection between use of digital media and sleep deprivation, as yet they do not have a definite answer as to what causes this. But they believe that previous observations and studies do provide answers.
“We know that light affects the biological mechanisms that delay sleep and the circadian rhythm. Computer games or television shows can generate excitement and make sleep more difficult,” Pallesen says. “However, it can not be ruled out that insomnia and delays in sleep patterns lead to people lying awake for longer at bedtime, thus resorting to electronic media for entertainment.”
“We know that light in the evening and night normally delay sleep and the circadian rhythm. In addition, computer games or television shows may generate excitement and make sleep more difficult,” Pallesen says. “However, it can not be ruled out that insomnia and a delayed sleep phase lead people to be more awake in bed, and that they because of this resort to electronic media for entertainment.”
Reserve the bed for sleep and sex
Electronic devices in the bedroom serve as distractions and make it harder to sleep, according to Pallesen and his fellow researchers. He mentions accidents as a theoretical parallel, where people may relive incidents because they encounter certain emotion upon revisiting the scene of an accident.
Professor Pallesen therefore recommends that people with insomnia issues keep the bedroom free of television sets, mobile phones, games consoles, computers and other electronic devices.
“The bedroom should be reserved for sex and sleep”, says Professor Ståle Pallesen.
(Translated from the Norwegian by Sverre Ole Drønen.)