The stress of daily life has sparked a new phenomenon - sleep texting.
People with the rare condition send incoherent text messages while asleep to their friends and family - completely unaware that they are doing it.
Sleep specialist Dr David Cunnington, of Melbourne Sleep Disorder Centre in Australia, said patients had reported incidents of sleep texting - and he has advised people to leave their mobile phones outside the bedroom.
He said: “Sleeping text is one of those things that happens, but it is very rare, and certainly not a common trend.”
Dr Cunnington described sleep texting as the result of people having too much to do during waking life.
He explained: “People are doing so much during a normal day that it can mean that they feel like they're ‘on call’ even at night.”
“Because it's so easy to receive emails constantly, and get notifications from smartphones, it becomes more difficult for us to separate our waking and sleeping lives.”
Dr Cunnington said people struggling to get a quality night's sleep should keep their phones out of the bedroom.