Ian Oswald, a sleep researcher and psychiatrist from the University of Edinburgh, sought to discover whether people could sleep through anything.
So, in 1960, he taped open volunteers’ eyes and placed flashing lights 50 cm in front of them. He also exposed them to electric shocks and loud music.
However, all the subjects eventually fell asleep, some within just 12 minutes. His conclusion – the regular and repetitive rhythm of the stimulus allowed them to doze off.
