Mirror- and eye-gazing perceptions in advanced psychometric perspective: Preliminary findings

In healthy individuals, investigations of cognitive processes and factors underlying mirror self-consciousness are compelling. Under a low level of face illumination, mirror- and eye-gazing protocols reliably induce anomalous self-experiences in healthy individuals, although the dimensionality of such perceptions has been debated in terms of three rival hypotheses rooted in one-, two-, and three- factor models. We explored the factor structure of anomalous experiences of mirror and eye gazing via advanced techniques grounded in Modern Test Theory and Rasch scaling. A sample of 90 healthy individuals participated in eye-gazing sessions using 45 dyads of randomly paired subjects; afterward, they responded to the Strange-Face Questionnaire (SFQ; Caputo, 2019) that inventories anomalous experiences of the other’s face. We found that the Derealization, Depersonalization, and Dissociative Identity items measured clearly discriminable constructs. Competitive model testing with structural equation modeling (SEM) also showed that the formulation “Derealization → Depersonalization → Dissociative Identity” contained no other links among these three factors and that each item contributed to a single factor only. The corresponding idea of “progressive dissociation” might imply a successively triggered or “layered” involvement of brain areas, from early processing of external world (i.e., the visual face) to intermediate processing of internal world (i.e., the bodily face) and to late processing of the subject’s identity (i.e., the identity self), as the intensity of state dissociation increases.