A full moon may be to blame for sleepless nights after all.

Scientists at the University of Basel, Switzerland, say they have found the first reliable evidence that sleep patterns are influenced by lunar changes. The study, published in Current Biology, shows brain activity related to deep sleep in volunteers dropped by 30 per cent around the full moon. The study subjects also took longer to fall asleep and had shorter nights.

"It could be important," said Eric Chudler, executive director of the Centre for Sensorimotor Neural Engineering at the University of Washington in Seattle.

The Swiss researchers are not "saying the moon controls the person's sleep pattern; they're saying the body has an internal clock that's similar to the lunar cycle. It's different to the traditional myth."

The full moon has been blamed for murder and mayhem since ancient times. The term lunacy was coined in the 16th century to refer to an intermittent form of insanity believed to be related to the moon. For generations, people have passed down tales of werewolves and other moon-related curses.

Researchers at the Centre for Chronobiology at the Psychiatric Hospital of the University of Basel set out to examine 33 volunteers' circadian rhythms, which are physical, mental and behavioral changes that respond to light and darkness over a 24-hour cycle.

Christian Cajochen, head of the Centre for Chronobiology, said he realised some researchers believed there could be an impact from the moon and the team decided to go back over their study data and match it up with a lunar calendar.

Bloomberg