Core Neurocognitive Networks Functional Connectivity In Parkinson’s Disease With REM Sleep Behavior Disorder Based On Independent Component Analysis

Background : Parkinson’s disease(PD)patients with rapid eyes movement sleep behavior disorder(PD-RBD)often accompany with cognitive impairment.Increasing evidence indicates that the core neurocognitive networks play an important role in cognition decline,but it has not studied in PD-RBD.This study aims to test the hypothesis that functional connection(FC)changes within and between the core neurocognitive networks in PD-RBD,and the relationship with their cognitive function.Methods: Primary PD without dementia were included,according to the polysomnography they were divided into PD-RBD and PD-NRBD group.At the same time,age and sex matched healthy controls(HCs)were recruited.All subjects underwent resting-state functional MRI data collection and neuropsychological scale measurements.We used the independent component analysis(ICA)to select the main neurocognitive networks,included the Default mode networks(DMN),Central executive network(CEN),Salience network(SN)and frontoparietal network(FPN).Then we investigated the FC changes within and between those networks in the three groups.Pearson’s correlation analysis was applied to obtain the correlation between FC changes of those networks and cognitive function.Results: The PD-RBD showed decreased FC within posterior DMN(p-DMN)particularly in the posterior cingulate gyrus,and the lower FC within the p-DMN the lower score in Montreal Cognitive Assessment(MOCA),specifically in visuospatial/executive,abstraction and orientation function.The decreased FC in the p-DMN is also correlated with severer RBD.Furthermore,the FC between the p-DMN and SN,the left FPN and right FPN were also aberrant,and the FC abruption inter the left FPN and right FPN are consistent with the visuospatial/executive function.Conclusion: Our findings suggest that the core neurocognitive networks FC is associated with cognitive decline and severity of RBD in PD-RBD,the decreased FC in p-DMN and between the left FPN and right FPN maybe one of the pathophysiological basic of their progressive cognitive decline,and the decreased FC in p-DMN may contribute the RBD.