Hypnagogic experiences are generally referred to as hallucinatory or quasi-hallucinatory events taking place on falling asleep. The term "hypnagogic" (from the Greek hypnos = sleep, and agogos = conductor, leader) was intro- duced into the literature by Maury (1848). Other terms proposed include Mitchell's (1890) "praedormitium", Wey- gandt's "presomnal or anthypnic sensations" (Vihvelin 1948), Trömner's (1911) "hypnagogic phantasms", Arnold-Forster's (1921) "borderland state" experiences, Leroy's (1933) "visions of half-sleep", Archer's (1935) "oneiragogic" images, Critchley's (1955) "sleepening" state experiences, and "phantasmata" and "faces in the dark" (in: Leaning, 1925, p. 289). Mavromatis(1983, p.8)