Déjà vu in the laboratory: A behavioral and experiential comparison of posthypnotic amnesia and posthypnotic familiarity

This experiment aimed to create a laboratory analogue of deja vu. During hypnosis, 1 group of high hypnotizables completed a puzzle game and then received a posthypnotic amnesia suggestion to forget the game (PHA condition). Another group of highs were not given the game but received a posthypnotic familiarity suggestion that it would feel familiar (PHF condition). After hypnosis, all participants were given the game and described their reactions to it. Whereas 83% of participants in both conditions passed their respective suggestions, more in the PHF condition felt a sense of deja vu. An EAT inquiry revealed that they experienced sensory fascination and confusion about the source of familiarity, akin to everyday deja vu. These findings highlight the value of using hypnosis as a laboratory analogue of deja vu and provide a framework for investigating clinical manifestations of this phenomenon.