TY - JOUR
T1 - Graph theory analysis of resting-state functional magnetic resonance imaging in essential tremor
AU - Benito-León, Julián
AU - Sanz-Morales, Emilio
AU - Melero, Helena
AU - Louis, Elan D.
AU - Romero, Juan P.
AU - Rocon, Eduardo
AU - Malpica, Norberto
N1 - Funding Information:
Dr J.B.L. is supported by the National Institutes of Health, Bethesda, MD (NINDS #R01 NS39422), the European Commission (grant ICT-2011-287739, NeuroTREMOR), the Spanish Ministry of Economy and Competitiveness (grant RTC-2015-3967-1, NetMD—platform for the tracking of movement disorder), and the Spanish Health Research Agency (FIS PI12/01602 and FIS PI16/00451). Dr E.D.L. has received research support from the National Institutes of Health: NINDS #R01 NS094607 (principal investigator), NINDS #R01 NS085136 (principal investigator), NINDS #R01 NS073872 (principal investigator), and NINDS #R01 NS088257 (principal investigator). He has also received support from the Claire O'Neil Essential Tremor Research Fund (Yale University). Drs H.M., J.P.R., E.R., and N.M. are supported by the Spanish Ministry of Economy and Competitiveness (grant DPI-2015-68664-C4-1-R, NeuroMOD). Drs J.P.R. and E.R. are supported by the European Commission (grant ICT-2011-287739, NeuroTREMOR). Dr. E.R. is supported by the project ESSENTIAL (DPI2015-72638-EXP). The authors thank Drs Juan Álvarez-Linera and Juan Antonio Hernández-Tamames for their assistance to the project.
Publisher Copyright:
© 2019 Wiley Periodicals, Inc.
PY - 2019/11/1
Y1 - 2019/11/1
N2 - Essential tremor (ET) is a neurological disease with both motor and nonmotor manifestations; however, little is known about its underlying brain basis. Furthermore, the overall organization of the brain network in ET remains largely unexplored. We investigated the topological properties of brain functional network, derived from resting-state functional magnetic resonance imaging (MRI) data, in 23 ET patients versus 23 healthy controls. Graph theory analysis was used to assess the functional network organization. At the global level, the functional network of ET patients was characterized by lower small-worldness values than healthy controls—less clustered functionality of the brain. At the regional level, compared with the healthy controls, ET patients showed significantly higher values of global efficiency, cost and degree, and a shorter average path length in the left inferior frontal gyrus (pars opercularis), right inferior temporal gyrus (posterior division and temporo-occipital part), right inferior lateral occipital cortex, left paracingulate, bilateral precuneus bilaterally, left lingual gyrus, right hippocampus, left amygdala, nucleus accumbens bilaterally, and left middle temporal gyrus (posterior part). In addition, ET patients showed significant higher local efficiency and clustering coefficient values in frontal medial cortex bilaterally, subcallosal cortex, posterior cingulate cortex, parahippocampal gyri bilaterally (posterior division), right lingual gyrus, right cerebellar flocculus, right postcentral gyrus, right inferior semilunar lobule of cerebellum and culmen of vermis. Finally, the right intracalcarine cortex and the left orbitofrontal cortex showed a shorter average path length in ET patients, while the left frontal operculum and the right planum polare showed a higher betweenness centrality in ET patients. In conclusion, the efficiency of the overall brain functional network in ET is disrupted. Further, our results support the concept that ET is a disorder that disrupts widespread brain regions, including those outside of the brain regions responsible for tremor.
AB - Essential tremor (ET) is a neurological disease with both motor and nonmotor manifestations; however, little is known about its underlying brain basis. Furthermore, the overall organization of the brain network in ET remains largely unexplored. We investigated the topological properties of brain functional network, derived from resting-state functional magnetic resonance imaging (MRI) data, in 23 ET patients versus 23 healthy controls. Graph theory analysis was used to assess the functional network organization. At the global level, the functional network of ET patients was characterized by lower small-worldness values than healthy controls—less clustered functionality of the brain. At the regional level, compared with the healthy controls, ET patients showed significantly higher values of global efficiency, cost and degree, and a shorter average path length in the left inferior frontal gyrus (pars opercularis), right inferior temporal gyrus (posterior division and temporo-occipital part), right inferior lateral occipital cortex, left paracingulate, bilateral precuneus bilaterally, left lingual gyrus, right hippocampus, left amygdala, nucleus accumbens bilaterally, and left middle temporal gyrus (posterior part). In addition, ET patients showed significant higher local efficiency and clustering coefficient values in frontal medial cortex bilaterally, subcallosal cortex, posterior cingulate cortex, parahippocampal gyri bilaterally (posterior division), right lingual gyrus, right cerebellar flocculus, right postcentral gyrus, right inferior semilunar lobule of cerebellum and culmen of vermis. Finally, the right intracalcarine cortex and the left orbitofrontal cortex showed a shorter average path length in ET patients, while the left frontal operculum and the right planum polare showed a higher betweenness centrality in ET patients. In conclusion, the efficiency of the overall brain functional network in ET is disrupted. Further, our results support the concept that ET is a disorder that disrupts widespread brain regions, including those outside of the brain regions responsible for tremor.
KW - MRI
KW - biomarker
KW - essential tremor
KW - functional connectivity
KW - graph theory
KW - resting state
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U2 - 10.1002/hbm.24730
DO - 10.1002/hbm.24730
M3 - Article
C2 - 31332912
AN - SCOPUS:85069892217
SN - 1065-9471
VL - 40
SP - 4686
EP - 4702
JO - Human Brain Mapping
JF - Human Brain Mapping
IS - 16
ER -