Impaired face recognition and the mirrored-self misidentification delusion: recreating the delusion using hypnosis

Mirrored-self misidentification is the delusional belief that one's own reflection in the mirror is a stranger. Current theories suggest that this delusion can occur when two factors are present: a deficit in face processing which is responsible for the content of the delusion (Factor 1) and a deficit in belief evaluation which accounts for the failure to reject the delusional belief (Factor 2). Previous research has used hypnosis to model this delusion. This research has found that a suggestion in hypnosis either to see a stranger in the mirror (a fully-formed suggestion) or to not recognise the person in the mirror (a suggestion for Factor 1 alone) can produce a hypnotic delusion with features strikingly similar to the clinical condition. The present study sought to directly compare these two approaches to see which best approximated the clinical condition. Fifty-two high hypnotisable participants received a hypnotic suggestion to either see a stranger in the mirror (fully-formed) or to not recognise the person in the mirror (Factor 1 alone). Half of the participants received the suggestion while hypnotised and the other half received the suggestion in their normal waking state. Following the suggestion, participants were asked to look into a mirror and to describe what they could see. Participants who reported seeing someone other than themselves were then given a series of clinically inspired challenges to determine the resilience of their delusion. Results support the idea that both types of hypnotic suggestion can produce a highly compelling mirrored-self misidentification delusion which is resistant to challenge. In particular, results suggest that the Factor 1 suggestion in hypnosis is especially effective at producing the delusion and that the additional information contained in the fully-formed suggestion is unnecessary. Results are discussed in terms of the two-factor theory of delusions.