Do you have trouble sleeping at night?
Everyday technology such as smartphones and tablets could be affecting how much sleep you get, a survey suggests.
More than three quarters of those surveyed use devices with screens before going to sleep. However the blue light they emit can disrupt the body's natural processes.
A psychologist at the University of Hertfordshire, Professor Richard Wiseman, who was behind the survey, says six out of ten people are now getting less than seven hours sleep a night.