Playing videogames, using laptops and sending text messages before bed is causing increased sleeplessness, so says expert research.
A new American study by the National Sleep Foundation showed that 95 per cent of those questioned said they used some type of electronics in the hour before bed, with about two-thirds admitting they do not get enough sleep during the week.
Charles Czeisler of Harvard Medical School told Reuters that exposure to artificial light before bed increases alertness and suppresses the release of sleep-inducing hormone melatonin.
A third of 13-18 year-olds and 28 per cent of 19-29 year olds said they played video games before bedtime.
The former group were suffering the most, according to the study, with 22 per cent describing themselves as "sleepy". That's compared to only nine per cent of 46-64 years old.
"Kids today are getting an hour and a half to two hours less sleep per night than they did a century ago. That means that they are losing about 50 hours of sleep per month," said Czeisler.
"Parents should get these technologies out of the bedrooms of kids if they want them to do well (in school)."
The NSF report added that all this sleeplessness was having an impact on a national level, with people's productivity, mood, driving habits, sex lives and general health all suffering.
"Unfortunately, cell phones and computers, which make our lives more productive and enjoyable, may be abused to the point that they contribute to getting less sleep at night leaving millions of Americans functioning poorly the next day," explained NSF vice chairman Russell Rosenberg.