This is why I nap.
hip-nuh-GOJ-ik; -GOH-jik\, adjective:
Of, pertaining to, or occurring in the state of drowsiness preceding sleep.
It is of course precisely in such episodes of mental traveling that writers are known to do good work, sometimes even their best, solving formal problems, getting advice from Beyond, having hypnagogic adventures that with luck can be recovered later on.
-- Thomas Pynchon, "Nearer, My Couch, to Thee", New York Times, June 6, 1993
. . .the phenomenon of hypnagogic hallucinations, or what Mr. Alvarez describes as "the flickering images and voices that well up just before sleep takes over."
-- Christopher Lehmann-Haupt, "The Faces of Night, Many of Them Scary", New York Times, January 9, 1995