RT Journal Article SR Electronic T1 Exploring Anti-correlated Resting State BOLD Signals Through Dynamic Functional Connectivity and Whole-brain Computational Modeling JF bioRxiv FD Cold Spring Harbor Laboratory SP 085274 DO 10.1101/085274 A1 Murat Demirtaş A1 Matthieu Gilson A1 John D. Murray A1 Dina Popovic A1 Eduard Vieta A1 Luis Pintor A1 Vesna Prčkovska A1 Pablo Villoslada A1 Gustavo Deco YR 2016 UL http://biorxiv.org/content/early/2016/11/02/085274.abstract AB Resting-state functional magnetic resonance imaging and diffusion weight imaging became a conventional tool to study brain connectivity in healthy and diseased individuals. However, both techniques provide indirect measures of brain connectivity leading to controversies on their interpretation. Among these controversies, interpretation of anti-correlated functional connections and global average signal is a major challenge for the field. In this paper, we used dynamic functional connectivity to calculate the probability of anti-correlations between brain regions. The brain regions forming task-positive and task-negative networks showed high anti-correlation probabilities. The fluctuations in anti-correlation probabilities were significantly correlated with those in global average signal and functional connectivity. We investigated the mechanisms behind these fluctuations using whole-brain computational modeling approach. We found that the underlying effective connectivity and intrinsic noise reflect the static spatiotemporal patterns, whereas the hemodynamic response function is the key factor defining the fluctuations in functional connectivity and anti-correlations. Furthermore, we illustrated the clinical implications of these findings on a group of bipolar disorder patients suffering a depressive relapse (BPD).