Why our eyes move as we dream

Researchers think they have figured out why our eyes flicker when we have vivid dreams. Photo / iStock.

Our eyes move while we are asleep because we see images just as when we are awake, according to a study.

They flicker as they respond to what our unconscious mind 'sees'. Each flicker during Rapid Eye Movement (REM) sleep - the period when we experience vivid dreams - then signifies a "change of scene".

For the study, 19 epilepsy patients had electrodes fitted to monitor their brain activity for two weeks.

Research focused on the medial temporal lobe, an area of the brain that deals with concepts, but not directly with vision.

The results showed that, when patients were shown an image, the neurons in the medial temporal lobe burst into action.

Dr Yuval Nir, of Tel Aviv University in Israel, said that the neurons behaved in a "similar way" when participants were in REM sleep.

He said: "It becomes very probable that the eye movements represent some type of reset, or 'moving on to the next dream frame'. It's almost like when I was growing up and we had slide projectors. You move to the next dream slide, if you like."

Dr Nir, who conducted his research with the University of California, Los Angeles, said the findings may explain why blind people's eyes also flutter during sleep. He said: "Even people who are congenitally blind ... can still dream about their aunt coming to visit: her voice, the emotions and all the associations that go with that."

- Daily Mail