Open AccessGlobal efficiency of the motor network is decreased in Parkinson's disease in comparison with essential tremor and healthy controls
Author(s) -
Novaes Natalia Pelizari,
Balardin Joana Bisol,
Hirata Fabiana Campos,
Melo Luciano,
Amaro Edson,
Barbosa Egberto Reis,
Sato João Ricardo,
Cardoso Ellison Fernando
Publication year - 2021
Publication title -
brain and behavior
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.915
H-Index - 41
ISSN - 2162-3279
DOI - 10.1002/brb3.2178
Subject(s) - postcentral gyrus , parkinson's disease , supplementary motor area , sma* , neuroscience , basal ganglia , physical medicine and rehabilitation , motor control , psychology , motor symptoms , medicine , disease , functional magnetic resonance imaging , computer science , central nervous system , algorithm
Background Graph theory (GT) is a mathematical field that analyses complex networks that can be applied to neuroimaging to quantify brain's functional systems in Parkinson's disease (PD) and essential tremor (ET). Objectives To evaluate the functional connectivity (FC) measured by the global efficiency (GE) of the motor network in PD and compare it to ET and healthy controls (HC), and correlate it to clinical parameters. Methods 103 subjects (54PD, 18ET, 31HC) were submitted to structural and functional MRI. A network was designed with regions of interest (ROIs) involved in motor function, and GT was applied to determine its GE. Clinical parameters were analyzed as covariates to estimate the impact of disease severity and medication on GE. Results GE of the motor circuit was reduced in PD in comparison with HC ( p .042). Areas that most contributed to it were left supplementary motor area (SMA) and bilateral postcentral gyrus. Tremor scores correlated positively with GE of the motor network in PD subgroups. For ET, there was an increase in the connectivity of the anterior cerebellar network to the other ROIs of the motor circuit in comparison with PD. Conclusions FC measured by the GE of the motor network is diminished in PD in comparison with HC, especially due to decreased connectivity of left SMA and bilateral postcentral gyrus. This finding supports the theory that there is a global impairment of the motor network in PD, and it does not affect just the basal ganglia, but also areas associated with movement modulation. The ET group presented an increased connectivity of the anterior cerebellar network to the other ROIs of the motor circuit when compared to PD, which reinforces what it is known about its role in this pathology.