Subtypes of Psychotic-Like Experiences and Their Significance for Mental Health

Abstract

More recently, the interest in studying subclinical psychosis has increased, as it might provide critical information regarding mechanisms that are implicated in the exacerbation of subclinical symptoms and the maintenance of mental health. However, psychosis research has tended to focus on clinical outcomes and not to differentiate between subtypes of psychotic-like experiences (PLE) that might differ regarding their psychopathological significance. Importantly, this might have obscured a more accurate picture of the complex structure of psychosis and the significance of particular risk and protective factors. Notably, while studies point toward a continuity of psychotic experiences and accompanying factors across the general population, there is evidence indicating that some PLE in healthy individuals might also be associated with a weaker expression of other subclinical symptoms, increased well-being and even resilience to some degree. Importantly, such findings might have implications on strategies in psychosis prevention and therapy, early detection, as well as the construction of continuum models of psychosis. The present chapter aims at drawing together findings that necessitate a more differentiated view and assessment of PLE. It intends to provoke new questions that might offer starting points for future investigations, such as longitudinal studies investigating the interplay of subclinical symptoms.

Psychotic-Like Experiences: A Challenge in Definition and Assessment

“…In line with other researchers, we support the idea of conceptual clarity, consensus, and clear definitions regarding PLEs and associated concepts ( 9 , 13 , 25 ).…”

“…Moreover, the development and agreed upon use of a or a few “gold standard” assessment tools might help to gather more comparable data on PLEs concerning prevalence rates, prognosis, and other outcomes. As stated by other authors ( 13 ), longitudinal studies on PLEs and especially different PLE subtypes, might help to give more insight into the question why some individuals with PLEs develop mental disorders and others stay at the healthy end of the psychosis spectrum. Consequently, untangling this entanglement of PLE terms, definitions, and assessment tools might result in gathering more knowledge toward new prevention strategies and treatment approaches.…”

“…New approaches aiming for more subtle signs of reality distortion have created assessment tools for “exceptional experiences” (EEs) defined as deviations from experiences consistent with typical “reality models” ( 51 ) including hearing voices of beloved dead ones, déjà-vus, or out-of-body experiences ( 52 ). While EEs were first assumed as PLEs at the healthy end of the psychosis spectrum, the association with psychological problems ( 52 ) might need further clarification ( 13 ). Until now, there is no consensus about an agreed upon “gold standard” PLE assessment tool, and the multitude of assessment tools examining PLEs is striking.…”

“…The concept of psychosis as a transdiagnostic and extended phenotype (10) has resulted in the discussion about the redefinition of the concept and name of schizophrenia (11) and, moreover, in the examination of subclinical psychotic experiences (12)(13)(14) and the identification of PLEs as early indicators of psychosis onset (15,16). However, the variety of definitions and assessment tools of PLEs has been postulated to contribute to the discrepancy of findings regarding prevalence rates (17)(18)(19)(20) and persistence rates (21)(22)(23)(24).…”

The Community Assessment of Psychic Experiences-Positive scale (CAPE-P15) accurately classifies and differentiates psychotic experience levels in adolescents from the general population

“…Over the last years, the focus of psychosis research has increasingly shifted to non-clinical populations [ 24 ], as authors have argued that systematic and standardized screening for PE could be feasible in community and educational settings [ 25 – 27 ]. One of the most frequently used screening tools is the Community Assessment of Psychic Experiences (CAPE) [ 28 ], which was created following the theoretical framework of the extended subclinical psychosis phenotype [ 24 ]. The original version (CAPE-42) [ 29 ] has good discriminant validity and good test-retest reliability [ 19 , 30 ].…”