Altered functional connectivity of nucleus accumbens subregions associates with non-motor symptoms in Parkinson's disease

Aims This study aimed to identify the functional connectivity (FC) changes of nucleus accumbens (NAc) subregions and characterize the association of network changes and non-motor symptoms (NMS) in Parkinson's disease (PD). Methods We enrolled 129 PD patients and 106 healthy controls from our center and the PPMI (Parkinson's Progression Markers Initiative) database. The FC of the bilateral core and shell of the NAc were measured and compared between the two groups. We further used partial least squares correlation to reveal the relationships between altered FC of NAc subregions and manifestations of NMS of PD. Results The subregions of left core, left shell, and right core had reduced FC with extensive brain regions in PD patients compared with healthy controls. These three subregions were commonly associated with depression, anxiety, apathy, and cognitive impairment. Moreover, the left core and left shell were associated with excessive daytime sleepiness, whereas the right core was associated with olfactory impairment and rapid eye movement sleep behavior disorder. Conclusion This study for the first time identified the neural network changes of NAc subregions in PD and the associations between network changes and phenotypes of NMS. Our findings provide new insights into the pathogenesis of NMS in PD.

Automated summary

This study aimed to identify the functional connectivity changes of nucleus accumbens subregions in Parkinson's disease and characterize the association of network changes and non-motor symptoms. The results showed reduced connectivity between the subregions of nucleus accumbens and extensive brain regions in Parkinson's disease patients compared to healthy controls. These subregions were associated with depression, anxiety, apathy, cognitive impairment, excessive daytime sleepiness, olfactory impairment, and rapid eye movement sleep behavior disorder.