Ever tried to get to sleep by counting sheep?
It doesn't work, does it?
That's because counting sheep is too boring say two Oxford scientists.
The two researchers took 50 people who have trouble getting to sleep and asked a third of them to count sheep and another third to imagine a beach or a waterfall.
The rest were asked not to do either so they could compare the results.
Apart from a few who needed the toilet, those imagining the waterfall fell asleep 20 minutes earlier than usual.
The sheep counters actually stayed awake longer than usual!
One of the scientists, Angela Harvey, believes this is because creating an interesting scene in your mind uses lots of brain power and is much more interesting than thinking about the "same dirty old sheep".
According to New Scientist magazine, one in ten people find it very difficult to go to sleep.