AUTHOR=Ooi Leon Qi Rong , Wen Ming-Ching , Ng Samuel Yong-Ern , Chia Nicole Shuang-Yu , Chew Isabel Hui Min , Lee Weiling , Xu Zheyu , Hartono Septian , Tan Eng King , Chan Ling Ling , Tan Louis Chew-Seng TITLE=Increased Activation of Default Mode Network in Early Parkinson’s With Excessive Daytime Sleepiness JOURNAL=Frontiers in Neuroscience VOLUME=13 YEAR=2019 URL=https://www.frontiersin.org/journals/neuroscience/articles/10.3389/fnins.2019.01334 DOI=10.3389/fnins.2019.01334 ISSN=1662-453X ABSTRACT=Background and Objectives

The underlying neuropathology of excessive daytime sleepiness (EDS) remains elusive in Parkinson’s disease (PD). We aim to investigate neural network changes that underlie EDS in PD.

Methods

Early PD patients comprising eighty-one patients without EDS (EDS−) and seventeen patients with EDS (EDS+) received a resting state functional MRI scan and the Epworth Sleepiness Scale (ESS). Connectivities within the default mode network (DMN), motor and basal ganglia networks were compared between the EDS+ and EDS− groups. Correlations between network connectivity and the severity of EDS were investigated through linear regression.

Results

EDS+ patients displayed a trend of increased network connectivity of the posterior DMN (pDMN). A significant positive correlation was found between connectivity of the ventromedial prefrontal cortex in the pDMN and ESS.

Conclusion

EDS+ patients are likely to display increased activation in the DMN, suggesting neural compensation in early PD or impaired attentiveness due to mechanisms such as mind-wandering.