You'd think this was straight out of psycho (an adaptation of a book by Robert Bloch, by the way).
In psycho a psychiatrist (the young Simon Oakland) tells us in clinical terms what we've seen.
When, in succession, he made Vertigo (1958), North by Northwest (1959), psycho (1960), and The Birds (1963).
word-forming element meaning "mind, mental; spirit, unconscious," from Greek psykho-, combining form of psykhe (see psyche). It also was used to form compounds in Greek, e.g. psychopates "soul-beguiling."
psycho psy·cho (sī'kō)
A psychopath. adj.
psycho- or psych-
Mind; mental: psychogenic.
Mental activities or processes: psychomotor.
Psychology; psychological: psychosocial.
: a special psycho channel that I know nothing about
A crazy person; maniac; psychopath; nut: no buzzing broad, no nympho, no psycho, no bitch (1942+)
[probably fr psychotic; the form psychot, ''psychopath,'' is found by the 1940s]