16:30 - 18:00
Mon-H5-Talk 3--33
Mon-Talk 3
Room: H5
Chair/s:
Bruno Kopp
Alterations of Functional Network Topology Underlying Cognitive Flexibility and Stability in Schizophrenia
Mon-H5-Talk 3-3304
Presented by: Anoushiravan Zahedi
Maren Sundermeier 1, Isabel Standke 3, Ricarda I. Schubotz 1, 2, Udo Dannlowski 2, 3, Rebekka Lencer 2, 3, 4, Ima Trempler 1, 2, Anoushiravan Zahedi 1, 2
1 Institute of Psychology, University of Muenster, Fliednerstr. 21, 48149 Muenster, Germany, 2 Otto-Creutzfeldt-Center for Cognitive and Behavioral Neuroscience, University of Muenster, Fliednerstr. 21, 48149 Muenster, Germany, 3 Institute for Translational Psychiatry, University of Muenster, Albert-Schweitzer-Campus 1 (Gebäude A9a), 48149 Muenster, Germany, 4 Department of Psychiatry and Psychotherapy, University of Luebeck, Ratzeburger Allee 160, 23538 Luebeck, Germany
Recently, it has been suggested that brain dysconnectivity in patients with schizophrenia might contribute to the wide-ranging cognitive deficits that characterize the disease. Graph theoretical analysis offers a unique method for studying how architectural alterations in large-scale brain networks may contribute to cognitive impairments in these patients. Implementing this technique, we analyzed the functional brain activity during a predictive switch-drift task from 22 patients with schizophrenia and 22 matched healthy controls. We specifically calculated task-based global graph measures for the functional networks that were activated during expected trials, trials requiring a flexible updating of predictions, and trials that required the stabilization of predictions. By implementing multivariate Bayesian generalized linear models, we found functional network alterations during all event types, which indicated less centralized, less integrated, and simultaneously less segregated network topology in patients with schizophrenia compared to controls. In addition, the rate of correctly detected switches, requiring flexible updating of internal models, predicted global graph measures differently for patients compared to controls. In particular, lower cognitive flexibility in patients was associated with stronger deficits regarding the integration of functional networks. Overall, the results suggest that the functional network topology in schizophrenia is less optimally organized compared to the neurotypical brain, which results in less flexible and stable cognitive processing.
Keywords: graph theory; connectome; cognitive control; executive functions; task-based fMRI; cognitive performance