SUMMARY Delusions are psychotic symptoms that contribute to significant emotional distress, poorer quality of life, functional impairment, hospitalization and violence. Delusions are treatment-resistant in many patients. Mechanistic understanding of delusion severity remains elusive, limiting treatment advancement. Abnormal belief updating is a proposed mechanistic framework of delusions with accumulating evidentiary support. My K23 mentored patient-oriented career development award proposes a longitudinal examination of delusion severity and belief updating in psychotic disorder patients recovering from an acute episode of psychosis. This project will use computational and functional neuroimaging (fMRI) approaches to 1) determine how belief updating parameters change throughout six months of recovery from an acute delusional state, and 2) characterize neurobiological correlates of belief updating parameters as symptom severity changes. I am an Assistant Professor in the Department of Psychiatry and Behavioral Sciences at Vanderbilt University Medical Center on the Clinician Scientist-Investigator (tenure) Track. My long-term career goal is to build an independent research program that employs sophisticated cognitive neuroscience techniques to test mechanistic models of psychosis, and then use that knowledge to develop and test novel interventions. These goals are being supported by a K23 mentored career development award, that includes training in: 1) the computational and cognitive neuroscience of delusions, 2) longitudinal research design and statistics, and 3) intervention research to prepare the me for a translational research career. Mentored training and completion of the proposed project will provide me the skills and experience necessary to launch a successful independent research career. I am therefore requesting an administrative supplement to my K23 parent award following the critical life event of childbirth. In January 2024, I gave birth to my child, and I am currently on parental leave. This critical life event was not anticipated when I developed my K-award timeline and career development goals. While my child is still small, I will have reduced flexibility to oversee data collection and less predictable time set aside for time-intensive analysis of neuroimaging data and in-person coursework. I am therefore requesting supplemental funds to support effort of a research assistant and neuroimaging data analyst, in addition to asynchronous online coursework focused on longitudinal data analysis. These additional resources will support final data collection on my parent award and analysis of study aims, as I move into the final years of my award period. This will support the continuity of my research and career development during this critical time in my life; it will allow me to continue on my current research trajectory towards becoming an independent investigator studying the cognitive mechanisms of psychosis and developing novel in...