Compulsive social media use could be a sign that you’re not getting enough sleep, according to a study by researchers at the University of California. They demonstrated that lack of sleep — in addition to affecting mood and productivity — leads to more frequent online activities such as browsing Facebook. The study’s lead researcher, Gloria Mark, said: ‘When you get less sleep, you’re more prone to distraction. If you’re being distracted, what do you do? You go to Facebook. It’s lightweight, it’s easy, and you’re tired.’ The researchers looked at data from 76 undergraduates, collected over one week. The study controlled for students’ gender, age, workload and deadlines and relied on sensors to objectively gauge their behaviour, activities and stress levels. Students’ computers and smartphones were equipped with logging software, and time stamps recorded when they switched from one application to another and when they spoke on the phone or sent a text. They were asked to fill out a sleep survey every morning. Mark said the study’s findings show a direct connection between lack of sleep, worsening mood and greater instances of Facebook browsing. She also found that the less sleep people have, the more frequently their attention shifts among different computer screens, suggesting increased levels of distraction. It is well established that sleep deprivation can cause workplace accidents and make drivers fall asleep at the wheel. Now experts in human-computer interaction want to know how sleep loss impacts people so they can improve products. ‘There have been lots of studies on how information technology affects sleep. We did the opposite: we looked at how sleep duration influences IT usage,’ Mark said.