 Scientific evidence that lucid dreaming is real and a genuine sleep phenomenon comes from laboratory studies (Hearne 1978; LaBerge et al. 1981) showing lucid dreamers can use specific, pre-arranged patterns of eye movements (e.g., right-left-right-left) to signal in real-time that they are now lucid and engaging in dream experiments. These signals are clearly identifiable on the EOG and suggest a correspondence between dream-eye movements and real-eye movements (as predicted by the so-called scanning hypothesis; see Dement &amp; Kleitman 1957; Leclair-Visonneau et al. 2010). Retrospective reports confirm that the dreamer really was lucid and signalled lucidity (Dresler et al. 2012; Stumbrys et al. 2014).