PhD Project - Predicting Yourself

Orygen, The National Centre of Excellence in Youth Mental Health and Centre for Youth Mental Health

• Hierarchical predictive processing and anomalous self-experience  in early stages of psychotic disorders

The hierarchical predictive processing (HPP) approach to neural mechanisms underlying perception, cognition and action has gained substantial attention in recent work in neuroscience. In brief, HPP models describe counterflowing top-down prediction/expectation signals and bottom-up prediction error signals. Successful perception, cognition and action are associated with successful suppression (“explaining away”) of prediction errors. Recent empirical work indicates that aberrant predictive processing (e.g., an over- or an underweighting of prediction errors) may play a role in the onset of positive psychotic symptoms, such as delusions and hallucinations. There has also been recent theoretical work indicating that aberrant hierarchical predictive processing may be of relevance to basic self-disturbance, which refers to an implicit sense of agency and ownership of experience, and which has been suggested to be a core trait marker of schizophrenia spectrum disorders. However, this has not yet been directly empirically tested and will form the basis of the current project. The project will involve a series of experimental studies (behavioural, neurophysiological and neuroimaging) assessing predictive processing in relation to clinical symptoms and self-disturbances in early psychosis patients (first episode psychosis patients and those at high clinical risk), as well as a healthy comparison group. Findings may have bearing on neurophenomenological models of the aetiology of psychotic disorders, and contribute to early identification and treatment of these psychiatric disorders.

• For further information please contact Professor Nelson - barnaby.nelson@orygen.org.au