Psychotic disorders carry social and economic costs for sufferers and society. Recent evidence highlights the risk posed by urban upbringing and social deprivation in the genesis of paranoia and psychosis. Evidence based psychological interventions are often not offered because of a lack of therapists. Virtual reality (VR) environments have been used to treat mental health problems. VR may be a way of understanding the aetiological processes in psychosis and increasing psychotherapeutic resources for its treatment. We developed a high-fidelity virtual reality scenario of an urban street scene to test the hypothesis that virtual urban exposure is able to generate paranoia to a comparable or greater extent than scenarios using indoor scenes. Participants ( ) entered the VR scenario for four minutes, after which time their degree of paranoid ideation was assessed. We demonstrated that the virtual reality scenario was able to elicit paranoia in a nonclinical, healthy group and that an urban scene was more likely to lead to higher levels of paranoia than a virtual indoor environment. We suggest that this study offers evidence to support the role of exposure to factors in the urban environment in the genesis and maintenance of psychotic experiences and symptoms. The realistic high-fidelity street scene scenario may offer a useful tool for therapists. 1. Introduction Psychosis, and psychotic disorders such as schizophrenia, is characterized by the presence of hallucinations (false perceptions) and delusions (false beliefs). It has become clear in recent years that the marked heterogeneity in the rates of schizophrenia and psychotic disorders across population groups [1] can be partly explained by urban birth and upbringing, migration, ethnicity, and what Cantor-Graae and Selten have termed “social defeat” [2, 3]. A particularly important recent body of research is the MRC AESOP study that demonstrated a twentyfold rate increase in the incidence of psychosis in London, compared with Nottingham and Bristol, and the very highest rates being within the Black and ethnic minority groups [4–8]. These epidemiological findings have strengthened continuum models of psychosis [9], which state that psychotic-like experiences are distributed in a normal nonclinical population and might be dependent upon many of the same variables as causally responsible for cases of the disorder [10]. Trying to connect psychological, biological, and social models of psychosis, and relating these to psychotic experiences and urbanicity in the general population, has become increasingly
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