12-Distinct between-network functional connectivity changes in Parkinson’s disease related to cognition: A follow-up study

Abstract

Introduction Patients with Parkinson’s disease (PD) show abnormal functional connectivity in large-scale brain networks. We explored resting state connectivity among the main networks, including the default mode network (DMN), dorsal attentional network (DAN), frontoparietal control network (FPCN) and visual network (VN) in PD patients with and without cognitive impairment (PD-MCI and PD-NC). Methods 51 healthy controls (HC), 17 PD-NC and 24 PD-MCI were enrolled. Participants underwent cognitive testing and MRI examination at the baseline and at one year follow-up. Resting-state fMRI data were analysed and the inter-network connectivity was calculated between the FPCN and other networks. Spearman correlations with attention and executive domain z-scores were calculated. Results FPCN-DAN, FPCN-VN and FPCN-DMN connectivities were significantly reduced in PD-NC as compared to HC. The connectivities decreased in the order HC > PD-MCI > PD-NC. At one-year follow-up, significant increases in FPCN-VN and FPCN-DMN connectivities were observed in the merged PD group, while no changes were detectable in the HC group. Conclusion Decreased connectivity between the FPCN and other networks was observed already in PD-NC. PD-MCI tend to compensate for their cognitive deficit by increasing between-network connectivities. Moreover, the between-network connectivities were increased at the follow-up in the PD-all group, while no changes were found in HC. Acknowledgement: Supported by the EU Joint Programming initiative within Neurodegenerative Diseases, funded by the Norwegian Strategic Research Council (APGeM—Preclinical genotype-phenotype predictors of Alzheimer’s disease and other dementias, grant agreement number 3056-00001). We acknowledge also the core facility MAFIL of CEITEC supported by the MEYS CR (LM2015062 Czech-BioImaging).