More than simply ‘anomalous’: Elevating the role of phenomenal experience within delusional misidentification

Within the field of cognitive neuropsychiatry, the two-stage model of delusional misidentification represents the dominant approach to explanations of Capgras and Frégoli delusions. A deficit at the first stage typically involves neuropsychological disruption, which is said to produce some kind of anomalous experience. In addition, a second-stage deficit in belief formation and/or revision is posited. The aim of this paper is to challenge the two-stage model’s unidirectional approach to explanation - from neurological disruption, to anomalous experience, to full blown delusion - which has resulted in the marginalisation of the role played by the patient’s underling phenomenology in accounting for the formation and maintenance of the delusional belief. By comparing the experiences of Capgras and Frégoli patient with those suffering from other related, but non-delusional, facial recognition pathologies, and mapping these differences onto functional disruptions known to occur within the facial recognition system, a description of the delusional patient’s experience emerges that is necessarily something more than simply “anomalous”. A two-stage interactionist model is thus proposed which maintains that the anomalous experience acts to validate the delusional belief - formed as a result of some form of second-stage deficit - but, importantly, and in addition, that this belief authenticates the content of the experience: belief and experience are thus congruent. As a consequence, the Capgras patient actually has an “impostor” experience; the Frégoli patient, a “same person in disguise” experience.