The solution came from a simple, elegant idea: because the muscles controlling eye movement are not paralysed during REM sleep the way most other voluntary muscles are, a lucid dreamer could, in principle, signal to waking researchers by moving their eyes in a specific, pre-arranged pattern the instant they became aware they were dreaming.
British psychologist Keith Hearne, working at the University of Hull with his research subject Alan Worsley, achieved exactly this on the morning of 12 April 1975: Worsley, on becoming lucid within a dream, executed the agreed left-right eye-movement sequence, which Hearne captured clearly on the REM polygraph recording, providing the first objective, timestamped proof that communication from inside a dream to the waking world was possible.
American psychophysiologist Stephen LaBerge, working independently and unaware of Hearne's result, achieved the same eye-signal verification at Stanford University on 13 January 1978, and went on to publish the method in peer-reviewed journals from 1980, giving the finding wide academic visibility that Hearne's unpublished thesis work had not initially received.
Since then, hundreds of studies using EEG, and later fMRI, have confirmed lucid dreaming as a distinct, measurable neurophysiological state, and it is now used clinically, including in nightmare-reduction therapy, standing alone among the claims in this atlas as a psi-adjacent report that laboratory science has fully confirmed rather than left contested or unreplicated.