The self, neuroscience and psychosis study: Testing a neurophenomenological model of the onset of psychosis.

AIM: Basic self disturbance is a putative core vulnerability marker of schizophrenia spectrum disorders. The primary aims of the Self, Neuroscience and Psychosis (SNAP) study are to: (1) empirically test a previously described neurophenomenological self-disturbance model of psychosis by examining the relationship between specific clinical, neurocognitive, and neurophysiological variables in UHR patients, and (2) develop a prediction model using these neurophenomenological disturbances for persistence or deterioration of UHR symptoms at 12-month follow-up. METHODS: SNAP is a longitudinal observational study. Participants include 400 UHR individuals, 100 clinical controls with no attenuated psychotic symptoms, and 50 healthy controls. All participants complete baseline clinical and neurocognitive assessments and electroencephalography. The UHR sample are followed up for a total of 24 months, with clinical assessment completed every 6 months. RESULTS: This paper presents the protocol of the SNAP study, including background rationale, aims and hypotheses, design, and assessment procedures. CONCLUSIONS: The SNAP study will test whether neurophenomenological disturbances associated with basic self-disturbance predict persistence or intensification of UHR symptomatology over a 2-year follow up period, and how specific these disturbances are to a clinical population with attenuated psychotic symptoms. This may ultimately inform clinical care and pathoaetiological models of psychosis.

Greater preference for eveningness is associated with negative symptoms in an ultra-high risk for psychosis sample.

AIM: Investigating biological processes in at-risk individuals may help elucidate the aetiological mechanisms underlying psychosis development, refine prediction models and improve intervention strategies. This study examined the associations between sleep disturbances, chronotype, depressive and psychotic symptoms in individuals at ultra-high risk for psychosis. METHODS: A sample of 81 ultra-high risk patients completed clinical interviews and self-report assessments of chronotype and sleep during the Neurapro clinical trial. Mixed regression was used to investigate the cross-sectional associations between symptoms and sleep disturbances/chronotype. RESULTS: Sleep disturbances were significantly associated with increased depressive and attenuated positive psychotic symptoms. Greater preference for eveningness was significantly associated with increased negative symptoms, but not with depressive or attenuated positive psychotic symptoms. CONCLUSION: Sleep disturbances and chronotype may impact the emerging psychopathology experienced by ultra-high risk individuals. Further, the preliminary relationship observed between greater preference for eveningness and negative symptoms offers a unique opportunity to treat negative symptoms through chronobiological approaches.