Neural network bases of healthy and aberrant belief updating
Prof. Dr. Tobias Donner
Prof. Dr. Tania Lincoln
Associated Post-doc resarcher based at UKE: Dr. Ayelet Arazi, a.arazi"AT"uke.de
Project in cooperation with Peter Murphy, National University of Ireland Maynooth
Dynamic belief updating is key for healthy cognition and seems to be impaired in mental disorders such as schizophrenia. Recent advances have yielded new insights into the large-scale brain circuit operations underlying dynamic belief updating. The reset of belief updating computations in networks of the cerebral cortex, triggered by the transient activation of brainstem arousal systems, may play a key role in this process. Clinical research has discovered aberrations of baseline arousal levels in schizophrenia. We propose to test the hypothesis that aberrations of baseline arousal reduce phasic arousal responses during belief updating; this impairs the large-scale cortical network resets required for updating the belief state following environmental changes. We plan to unravel this putative mechanistic cascade in the healthy human brain and quantify its aberrations in schizophrenia. Specifically, we aim to (i) identify large-scale signatures and decipher the functional role of cortical network resets following change points; (ii) unravel the dependence of task-evoked, phasic arousal responses, following change points, on baseline arousal levels; and (iii) quantify aberrations of phasic arousal and cortical network reset in schizophrenia. To these ends, we will combine behavioral modeling, arousal tracking in daily life through experience sampling, laboratory assessment of arousal through pupillometry and ECG, and magnetoencelphalographic (MEG) assessment of large- scale cortical network dynamics. We will assess network reset signatures in multiple pupillometry-MEG data sets from the healthy brain, and we will compare arousal and cortical belief updating dynamics between schizophrenia patients and healthy controls. This project will advance the fundamental understanding of healthy and aberrant belief updating and may pave the way for a biomarker assay of the interplay of brainstem arousal systems and cortical computation in schizophrenia.