Modelling the longitudinal development of psychosis during late childhood and early adolescence

Abstract

Psychosis being best conceptualised as a continuous construct extending to the general population questions the dichotomous approach used by the clinical model of having clearly differentiated disorder categories. During the past 15-20 years the continuum hypothesis has gained mounting support from research. Current debates of the psychosis continuum provide a more precise definition in regards to structural, phenomenological, and temporal continuity (Linscott & van Os, 2012). Also, the notion that more than one continuum exists is currently debated (Kaymaz & van Os, 2010; van Nierop et al., 2011). It is especially important to investigate how psychosis develops during childhood and adolescence with a focus on these current debates of the psychosis continuum as most clinical psychotic disorders are diagnosed during late adolescence and early adulthood (Harrop & Trower, 2001; Thompson, Pogue-Geile, & Grace, 2004).

Part one of the thesis (Chapters 2 and 3) models the reduction of psychosis experiences (PEs) from late childhood (around the age of 11) to early adolescence (around the age of 16). Results suggest that there may be a structural change of the psychosis construct around the age of 16, possibly due to a subgroup of adolescence who cease PEs due to psychosis being a part of the normative development before age 16 (Laurens & Hobbs, 2012).

Part two (Chapters 4, 5 and 6) deals with the question of how persistence (temporal continuity) develops during the same time period. The hypothesis that the co-occurrence of hallucinations and delusion is driven by primary hallucinatory experiences that are then explained via secondary delusion formation (Smeets et al.,2012) could not be supported. However, the question if this temporal ordering(hallucinations then delusions) entails more risk could not adequately be determined. Further longitudinal studies extending beyond the age of 16 and including direct markers of risk such as distress or help-seeking are needed to confirm and expand on the current findings.

Date of Award	Jul 2015
Original language	English
Supervisor	Mark Shevlin (Supervisor), Gary Adamson (Supervisor) & Jamie Murphy (Supervisor)