The Cerebellum Is a Common Key for Visuospatial Execution and Attention in Parkinson's Disease

Cognitive decline affects the clinical course in patients with Parkinson's disease (PD) and contributes to a poor prognosis. However, little is known about the underlying network-level abnormalities associated with each cognitive domain. We aimed to identify the networks related to each cognitive domain in PD using resting-state functional magnetic resonance imaging (MRI). Forty patients with PD and 15 normal controls were enrolled. All subjects underwent MRI and the Mini-Mental State Examination. Furthermore, the cognitive function of patients with PD was assessed using the Montreal Cognitive Assessment (MoCA). We used independent component analysis of the resting-state functional MRI for functional segmentation, followed by reconstruction to identify each domain-related network, to predict scores in PD using multiple regression models. Six networks were identified, as follows: the visuospatial-executive-domain-related network (R-2 = 0.54, p < 0.001), naming-domain-related network (R-2 = 0.39, p < 0.001), attention-domain-related network (R-2 = 0.86, p < 0.001), language-domain-related network (R-2 = 0.64, p < 0.001), abstraction-related network (R-2 = 0.10, p < 0.05), and orientation-domain-related network (R-2 = 0.64, p < 0.001). Cerebellar lobule VII was involved in the visuospatial-executive-domain-related and attention-domain-related networks. These two domains are involved in the first three listed nonamnestic cognitive impairment in the diagnostic criteria for PD with dementia (PDD). Furthermore, Brodmann area 10 contributed most frequently to each domain-related network. Collectively, these findings suggest that cerebellar lobule VII may play a key role in cognitive impairment in nonamnestic types of PDD.

Automated summary

This study identified networks related to each cognitive domain in Parkinson's disease using resting-state functional MRI. Six networks were associated with visuospatial-executive, naming, attention, language, abstraction, and orientation domains. Cerebellar lobule VII and Brodmann area 10 were highlighted as playing key roles in cognitive impairment in Parkinson's disease.