Not getting enough sleep? You're probably on Facebook, says new study

Wanting to look at how sleep duration could affect internet use, rather than how internet use affects sleep, the team recruited 76 UCI students and monitored them for a one-week period.

Using logging software the team could monitor participants' computers and smartphones to see how often they spoke on the phone, texted, or used applications.

Sensors were used to measure their behavior, activities, and levels of stress.

Participants were also asked to complete a survey every morning reporting on their sleep and to complete an end-of-day survey at night. The students also had to complete a general questionnaire and take part in an interview.

The researchers collected further data by asking participants during the week about their mood, the level of engagement in their work, and how difficult they were finding the task they were currently working on.

The study also looked into the idea of "sleep debt," the accumulated difference between the amount of sleep needed and the amount experienced.

After taking into account factors such as gender, age, university work load, and course deadlines, the results showed a direct connection between a chronic lack of sleep, a cranky mood, lower productivity, and also more time spent checking Facebook.

The researchers also found that not enough sleep leads people to be more easily distracted, with their attention flicking between different computer screens and apps.

"When you get less sleep, you're more prone to distraction," said lead researcher Gloria Mark, "If you're being distracted, what do you do? You go to Facebook. It's lightweight, it's easy, and you're tired."

The study's findings will be presented at CHI, a leading computer-human interaction conference in May in San Jose, California.

The effect of technology on quality of sleep has been shown in many previous studies, with a study published last month in the Journal of Child Neurology finding that teenagers who continue to text at night after they have switched out the lights experience poorer sleep and poorer grades than those who text with the lights on.

The study found once the lights go out, the "blue light" emitted from smartphones and tablets is intensified in the dark, delaying the release of melatonin, the hormone that makes you feel sleepy, and disrupting our sleep patterns and quality.