pseudohallucination a non-deceptive hallucination. An ordinary hallucination might be thought to comprise two components: (i) a sensory component, whereby one experiences an image or sensory episode similar in many respects to a veridical perceiving except in being non-veridical; and (ii) a cognitive component, whereby one takes (or is disposed to take) the image or sensory episode to be veridical. A pseudohallucination resembles a hallucination, but lacks this second component. In experiencing a pseudohallucination, one appreciates that one is not perceiving veridically. The source of the term seems to be the painter Wassily Kandinsky, who employed it (in 1885) to characterize a series of apparently drug-induced images experienced and pondered by a friend who recognized them, at the very time they were occurring, not to be veridical. Kandinsky’s account is discussed by Jaspers (in his General Psychopathology, 1916), and thereby entered the clinical lore. Pseudohallucinations may be brought on by the sorts of pathological condition that give rise to hallucinations, or by simple fatigue, emotional adversity, or loneliness. Thus, a driver, late at night, may react to non-existent objects or figures on the road, and immediately recognize his error. See also PERCEPTIO. J.F.H.