Todd Woodward

Biography

Dr. Todd Woodward is a Professor in the Department of Psychiatry at the University of British Columbia, Canada, Research Scientist at BC Mental Health and Substance Use Services (BCMHSUS) Research Institute, Director of the UBC Cognitive Neuroscience of Schizophrenia Laboratory (CNoS) and the UBC Brain Dynamics Laboratory. His research is focused on task-based functional brain imaging and fMRI and applied multivariate statistics for the study of the overlap between two sets of variables, with these paths converging on the study of the overlap between cognition and symptoms in schizophrenia at the level of brain networks. To date, Dr. Woodward has published over 180 peer-reviewed research manuscripts.

Description of the general focus of the symposium "Neuroimaging of abnormal brain functions in schizophrenia"

In general, this symposium is focused on the application of current neuroimaging methods in clinical neuroscience to understand schizophrenia. In more detail, the presented talks explore recent findings on abnormal brain activity in schizophrenia using state-of-the-art fMRI and EEG statistical methods, providing insights into the neural dynamics and their relation with psychopathology. For example, negative symptoms and cognitive deficits, origination of hallucinations and delusions, and hypo- or hyper-activation of specific networks. Finally, the talks will pivot to the implications of these findings on treatment, such as cognitive interventions or neuromodulation techniques.

Talk: "A macro-scale task-based BOLD-signal network important for re-evaluation and delusions."

Functional Magnetic Resonance Imaging (fMRI) provides information about the flow of blood-oxygen-level-dependent (BOLD) signal in the brain. The fact that BOLD signal flow forms into reliable configurations is well established, referred to as macro-scale BOLD brain networks. Timing information from cognitive tasks can be used to constrained variance in BOLD signal, and when submitted to a dimensional analysis, this produces macro-scale BOLD brain networks which span many tasks, and their function can be determined be observing their activation patterns over a range of task conditions. In this way, task-based fMRI can be used to determine which brain networks are involved in the symptoms of schizophrenia. For example, a brain network involved in re-evaluation of evidence showed reduced activation in patients experiencing delusions, as did another involved in inspection of evidence. This combination of glossing over evidence and neglecting re-evaluation may underlie the jumping to conclusions and fixedness that characterize delusions. For patients experiencing hallucinations, we see hyperactivation of a superior temporal gyrus (STG) network involved in external auditory perception, and hypoactivation in a linguistic processing network (LPN) for internal processing. This combination may underlie the impaired balance between internal and external linguistic processes (underactivity in networks involved in internal auditory imagery and overactivity in networks involved in speech perception) leading to externalizations in hallucinations. However, this must be integrated with the evidence that the on-line experience of a hallucination does not produce the same BOLD brain activity as true auditory perception. This approach to understanding the function of the brain networks underlying the symptoms of schizophrenia can lead to insights regarding optimal treatment through therapy or neuromodulation.