Grant: Project Grant

The rate of psychosis spectrum symptoms (PSS) is higher in children and adolescents compared to adults and can lead to poor outcomes, including increased suicidal thoughts and behaviours. Despite this, the focus of most psychosis research has been on examining perceptual and learning deficits associated with psychosis symptoms in high-risk adult populations, instead of investigating how these deficits may originate in youth. Recent evidence suggests that 75% of people who later experience a first episode psychosis had previously sought help for a mental health concern 3 years prior to their symptoms onset. To address this problem, this project aims to study the underlying neural and cognitive mechanisms of PSS using computational modelling, to identify individuals with learning patterns associated with PSS risk and track their stability over time. This will be done by modelling behaviour across tasks investigating auditory perception, positive and negative valence learning, social cognition, and cognitive control in conjunction with electrophysiological recordings. The study will also examine the validity of these predictors in capturing core disease mechanisms in clinical high-risk and first episode psychosis populations. The computational approach builds on hierarchical Bayesian models of cognition and highlights the interplay between prior beliefs and correction signals. This research project combines both cross-sectional and prospective study designs. The prospective aspect of the project will be made possible by leveraging the Toronto Adolescent and Youth Centre for Addiction and Mental Health Cohort study, a multimodal longitudinal study which follows 3,000 treatment-seeking youth and adolescents over 5 years. The expected outcome of this research is to gain a comprehensive understanding of the neural and cognitive processes that lead to psychosis in youth, with the aim of developing personalised computational models for early prevention of psychosis.