Hypnagogia
Hypnagogia is the experience of the transitional state from wakefulness to sleep: the
hypnagogic state of consciousness. The related words from the Greek are
agōgos "leading", "inducing",
pompe "act of sending", and
hypnos "sleep". The word
hypnagogia entered the popular psychology literature through Dr Andreas Mavromatis in his 1983 thesis, while
hypnagogic and
hypnopompic were coined by others in the 1800s and noted by Havelock Ellis. The term
hypnagogic was originally coined by Alfred Maury to name the state of consciousness during the onset of sleep.
Hypnopompic was coined by Frederic Myers soon afterwards to denote the onset of wakefulness. The term
hypnagogia is used by Dr Mavromatis to identify the study of the sleep-transitional consciousness states in general, and he employs
hypnogogic or
hypnapompic for the purpose of identifying the specific experiences under study. Mental phenomena that occur during this "threshold consciousness" phase include lucid dreaming, hallucinations, and sleep paralysis.