@article{57046a7898c94d65b41e225489decf32,
title = "Resting-State Functional Connectivity of the Thalamus in Complete Spinal Cord Injury",
abstract = "Background. Neuroimaging studies of spinal cord injury (SCI) have mostly examined the functional organization of the cortex, with only limited focus on the subcortical substrates of the injury. However, thalamus is an important modulator and sensory relay that requires investigation at a subnuclei level to gain insight into the neuroplasticity following SCI. Objective. To use resting-state functional magnetic resonance imaging to examine the functional connectivity (FC) of thalamic subnuclei in complete SCI patients. Methods. A seed-based connectivity analysis was applied for 3 thalamic subnuclei: pulvinar, mediodorsal, and ventrolateral nucleus in each hemisphere. A nonparametric 2-sample t test with permutations was applied for each of the 6 thalamic seeds to compute FC differences between 22 healthy controls and 19 complete SCI patients with paraplegia. Results. Connectivity analysis showed a decrease in the FC of the bilateral mediodorsal nucleus with right superior temporal gyrus and anterior cingulate cortex in the SCI group. Similarly, the left ventrolateral nucleus exhibited decreased FC with left superior temporal gyrus in SCI group. In contrast, left pulvinar nucleus demonstrated an increase in FC with left inferior frontal gyrus and left inferior parietal lobule in SCI group. Our findings also indicate a negative relationship between postinjury durations and thalamic FC to regions of sensorimotor and visual cortices, where longer postinjury durations (~12 months) is associated with higher negative connectivity between these regions. Conclusion. This study provides evidence for reorganization in the thalamocortical connections known to be involved in multisensory integration and affective processing, with possible implications in the generation of sensory abnormalities after SCI.",
keywords = "fMRI, mediodorsal nucleus, pulvinar nucleus, spinal cord injury, thalamus",
author = "Karunakaran, {Keerthana Deepti} and Rui Yuan and Jie He and Jian Zhao and Cui, {Jian Ling} and Zang, {Yu Feng} and Zhong Zhang and Alvarez, {Tara L.} and Biswal, {Bharat B.}",
note = "Funding Information: https://orcid.org/0000-0001-6448-9341 Karunakaran Keerthana Deepti PhD 1 Yuan Rui PhD 2 He Jie MD 3 Zhao Jian MD 4 Cui Jian-Ling MD 3 Zang Yu-Feng MD 5 Zhang Zhong MD 3 Alvarez Tara L. PhD 1 https://orcid.org/0000-0002-3710-3500 Biswal Bharat B. PhD 1 1 New Jersey Institute of Technology, Newark, NJ, USA 2 Stanford School of Medicine, Stanford, CA, USA 3 Hebei Medical University Third Affiliated Hospital, Shijazhuang, Hebei, China 4 Armed Police Force Hospital of Sichuan, Leshan, Sichuan, China 5 Hangzhou Normal University Affiliated Hospital, Hangzhou, Zheijang, China Bharat B. Biswal, Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA. Email: bbiswal@gmail.com 1 2020 1545968319893299 {\textcopyright} The Author(s) 2019 2019 American Society of Neurorehabilitation Background . Neuroimaging studies of spinal cord injury (SCI) have mostly examined the functional organization of the cortex, with only limited focus on the subcortical substrates of the injury. However, thalamus is an important modulator and sensory relay that requires investigation at a subnuclei level to gain insight into the neuroplasticity following SCI. Objective . To use resting-state functional magnetic resonance imaging to examine the functional connectivity (FC) of thalamic subnuclei in complete SCI patients. Methods . A seed-based connectivity analysis was applied for 3 thalamic subnuclei: pulvinar, mediodorsal, and ventrolateral nucleus in each hemisphere. A nonparametric 2-sample t test with permutations was applied for each of the 6 thalamic seeds to compute FC differences between 22 healthy controls and 19 complete SCI patients with paraplegia. Results . Connectivity analysis showed a decrease in the FC of the bilateral mediodorsal nucleus with right superior temporal gyrus and anterior cingulate cortex in the SCI group. Similarly, the left ventrolateral nucleus exhibited decreased FC with left superior temporal gyrus in SCI group. In contrast, left pulvinar nucleus demonstrated an increase in FC with left inferior frontal gyrus and left inferior parietal lobule in SCI group. Our findings also indicate a negative relationship between postinjury durations and thalamic FC to regions of sensorimotor and visual cortices, where longer postinjury durations (~12 months) is associated with higher negative connectivity between these regions. Conclusion . This study provides evidence for reorganization in the thalamocortical connections known to be involved in multisensory integration and affective processing, with possible implications in the generation of sensory abnormalities after SCI. spinal cord injury pulvinar nucleus mediodorsal nucleus fMRI thalamus New Jersey Commission on Spinal Cord Research https://doi.org/10.13039/100005200 CSCR15FEL002 edited-state corrected-proof typesetter ts1 Supplementary material for this article is available on the Neurorehabilitation & Neural Repair website at https://journals.sagepub.com/home/nnr . Declaration of Conflicting Interests The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. Funding The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was supported by a grant from the New Jersey Commission on Spinal Cord Research (CSCR15FEL002). ORCID iDs Keerthana Deepti Karunakaran https://orcid.org/0000-0001-6448-9341 Bharat B. Biswal https://orcid.org/0000-0002-3710-3500 ",
year = "2020",
month = feb,
day = "1",
doi = "10.1177/1545968319893299",
language = "English (US)",
volume = "34",
pages = "122--133",
journal = "Neurorehabilitation and Neural Repair",
issn = "1545-9683",
publisher = "SAGE Publications Inc.",
number = "2",
}