Resting-state Connectivity Between Dorsal Attention Network And Other Intrinsic Networks Of Parkinson's Disease With Freezing Of Gait

Background:Freezing of gait(FOG)is a common and complex manifestation of Parkinson disease(PD)and often associated with impairment of multiple cognitive domain.Cues which requires consistent attention of patients can reduce the episodes of freezing but the mechanism is not clearly.So,in this study we attempt to explore the role of attention network in freezing of gait through analysis the inter-network connections of multiple intrinsic brain networks.Methods:Forty-three idiopathic PD patients(21 with FOG(FOG+)vs 22 without FOG(FOG-))and 18 healthy controls(HC)were recruited and evaluated clinically.All participants underwent 3.0T magnetic resonance imaging(MRI)to collect structural and functional images.Data-driven independent component analysis was used to evaluate the intra-network and inter-network connectivity changes in networks of interest,namely,resting-state networks associated with attention,execution,visual and sensory motor functions.Results:Compared to FOG-,the intra-network connectivity of the sensory motor network(SMN)and of the visual networks was decreased,while the connectivity of the default mode network(DMN)was increased significantly in FOG+.In addition,these connection changes were associated with worse score on motor,visual-spatial,and executive function tests.Furthermore,positive inter-network connectivity between the dorsal attention network and the primary visual cortex,between the dorsal attention network and the sensory motor network,and between the sensory motor network and the primary visual cortex was decreased and even disappeared in PD with FOG.Negative inter-network connectivity between the dorsal attention network and the default mode network was found in the patient groups but not in the HC.Conclusion:Functional connectivity was changed in multiple intra-networks in patients with freezing of gait.Inordinate inter-network connectivity between the dorsal attention network and other intrinsic networks may contribute to the mechanism of freezing.