Psychosis has many definitions, but most refer to a breakdown that occurs in the ability of a person to form a coherent sense of reality, manifesting as false perceptions (hallucinations) or false beliefs that are not shared by others (delusions). It is often referred to as 'reality distortion.' It should be pointed out that not every hallucination or delusion is a sign of psychosis, and the determination of what makes a belief or perception true or false rests upon the assumption of a shared sense of what constitutes reality. At a philosophical or political level, people will dispute the nature of reality, but we take a primarily medical/normative approach, where these disputes have little relevance. In this approach, individuals have experiences that fall outside of their regular cultural context and are associated with both an impaired ability to function and distress. These sorts of experiences with reality distortion commonly occur with other 'symptoms,' such as depression and anxiety.  The most common diagnostic labels we use for psychotic experiences include: schizophrenia, schizoaffective disorder, or sometimes, just 'unspecified psychosis,' when a person's experience does not fit neatly into the categories defined in the Diagnostic and Statistical Manual (DSM-5). For more information about psychosis and schizophrenia, you can watch the video below. Understanding what happens in the brain to cause psychosis, and finding better ways to treat it, has been one of the central themes of my research.

Early Detection, Intervention and Prevention of Psychosis Program (EDIPPP)

The Early Detection and Intervention for the Prevention of Psychosis Program (EDIPPP) was designed to test the effectiveness of early detection and preventive intervention (e.g. PIER in Greater Portland, ME) across the United States in a large, ethnically, and geographically diverse population, in 6 typical mental health agencies and settings. The goal was to evaluate whether early intervention, ie, prior to onset of psychosis, with young people at clinical high risk could delay or prevent the development of frank psychosis and reduce functional impairment, in typical and diverse populations and clinical settings. It will also generate rapid referrals of youths at clinical high risk of psychosis by creating a network of professionals and community members trained to identify signs of early psychosis.

Completed Studies

Heightened stress sensitivity is a common characteristic of schizophrenia and may be predictive of clinical and functional outcomes.

We have developed a new scale for the assessment of psychological stress in psychosis (Psychological Stress Index; PSI). This work shows that both of the 18-item and 9-item PSI demonstrated good levels of reliability and could significantly discriminate patients from healthy controls. Both versions showed moderate convergence with self-report and clinician ratings of depression and anxiety, and superior predictive validity of 12-month follow-up clinical and functional outcomes compared to an existing measure of stress (Perceived Stress Scale).