Resting-state fMRI dynamics reveal increased state switching in the at-risk stage for psychosis
Poster B60, Friday, October 21, 11:30 am - 1:00 pm, Le Baron
Diana Wotruba1,2, Thomas Bolton3,4, Roman Buechler1, Anastastia Theodoridou1,5, Wulf Rössler1,2,6, Dimitri Van de Ville3,4, Karsten Heekeren1; 1University Hospital of Psychiatry Zurich, the Zurich Program for Sustainable Development of Mental Health Services (ZInEP), Switzerland, 2Collegium Helveticum, a joint Research Institute between the University of Zurich and the Swiss Federal Institute of Technology Zurich, Switzerland, 3Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, Switzerland, 4Faculty of Medicine, University of Geneva, Switzerland, 5Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital of Psychiatry, Switzerland, 6Laboratory of Neuroscience (LIM-27), Institute of Psychiatry, University of Sao Paulo, Sao Paulo, Brazil
Introduction: A fundamental feature of the human brain is its intrinsic organization into anticorrelated functional networks. The right anterior insula (rAI) has been proposed to play a causal role in regulating the competing activity of the Default-Mode (DMN)- and Task-Positive Network (TPN). A disturbed network-coordination has been associated with the confusion of internally and externally focused attention. Thus, the aim of this study was to examine the dynamic fluctuations of spontaneous brain activity in order to test to what extent rAI co-activation patterns (CAP) would be disturbed in the at-risk state for psychosis. Methods: Using resting-state fMRI data we characterized the dynamic fluctuations of spontaneous brain activity by probing rAI interactions through CAP-analysis in 28 subjects with basic symptoms, 19 suffering from attenuated and/or brief limited intermittent psychotic symptoms, and 29 controls. Results: In controls, the most frequent state displayed was rAI-TPN co-activation while the DMN was deactive, the second a rAI/DMN coactivation. Both at-risk groups engaged in shorter excursions in any state of rAI-coactivation and had a significantly smaller occurrence rate of the first state. Conclusion: The findings substantiate the pivotal role of rAI in governing TPN-to-DMN transitions, which seems to be dysfunctional in the psychosis at-risk state. Here, it is less likely to be active in concert with TPN-activation and DMN-deactivation and less able to remain active as part of a brain network, denoting increased state switching. This is, interestingly, regardless of symptom constellation.
Topic Area: Neuroimaging