Alteration of Resting-State Brain Sensorimotor Connectivity following Spinal Cord Injury: A Resting-State Functional Magnetic Resonance Imaging Study

Abstract

Motor and sensory deficits after spinal cord injury (SCI) result in functional reorganization of the sensorimotor network. While several task-evoked functional magnetic resonance imaging (fMRI) studies demonstrated functional alteration of the sensorimotor network in SCI, there has been no study of the possible alteration of resting-state functional connectivity using resting-state fMRI. The aim of this study was to investigate the changes of brain functional connectivity in the sensorimotor cortex of patients with SCI. We evaluated the functional connectivity scores between brain areas within the sensorimotor network in 18 patients with SCI and 18 controls. Our findings demonstrated that, compared with control subjects, patients with SCI showed increased functional connectivity between primary motor cortex and other motor areas, such as the supplementary motor area and basal ganglia. However, decreased functional connectivity between primary somatosensory cortex and secondary somatosensory cortex also was found in patients with SCI, compared with controls. These findings therefore demonstrated alteration of the resting-state sensorimotor network in patients with SCI, who showed increased connectivity between motor components, and decreased connectivity between sensory components, within the sensorimotor network, suggesting that motor components within the motor network increased in functional connectivity in order to compensate for motor deficits, whereas the sensory network did not show any such increases or compensation for sensory deficits.

Motor Cortex Reorganization and Repetitive Transcranial Magnetic Stimulation for Pain—A Methodological Study

“…They consider the finding as evidence of dynamic reshaping in the reorganized M1 (34). We have taken this observation further, suggesting that in a clinical population, remote effects may also be different, especially with concomitant connectivity alterations (26,51,52). Thus, if rTMS of the standard hotspot fails to induce pain relief, stimulation of an external reorganized site may afford a more positive response, as our results show.…”

“…In 2006 Lefaucheur and colleagues described pain relief from rTMS over M1 facial representation in patients with arm pain, and arm representation in facial pain, but their trial was based on single sessions only, with uncertainty of the generalizability of the results in clinical practice . In addition, their patients included those with poststroke pain in whom cortical rearrangement would likely be substantial . To our knowledge, our study is the first to demonstrate the relevance of using cortical reorganisation to target rTMS treatment for neuropathic pain.…”

“…Intracortical excitability changes (common in neuropathic pain) can be conveniently measured using paired-pulse TMS (28). Structural and functional connectivity can be reliably evaluated with diffusion tensor imaging (DTI) and tractography, and functional connectivity analysis using resting state fMRI, with M1 seed areas identified with task related fMRI (52,53). DTI and tractography show differences in rTMS responses in patients with post stroke pain (53).…”

Cortical plasticity after brachial plexus injury and repair: a resting-state functional MRI study

“…clude the precentral gyrus, postcentral gyrus, and supplementary motor area. Using seed-based methods to identify the SMN, Liu et al 17 and Min et al 22 found an absence of motor area activity on the side contralateral to the limb affected by BPI. Liu et al 17 found decreased interhemispheric rsFC between motor cortices in patients with BPI.…”

Giving priority to preclinical pain measures resistant to existing drugs for developing innovative analgesics

“…The resting‐state functional magnetic resonance imaging (rsfMRI), a neuroimaging technology to measure functional connectivity of multiple brain regions (Sakoğlu et al, ), is incorporated in the strategy. In the last decade, rsfMRI has detected abnormal functional connectivity, which is possibly associated with pathophysiology of chronic pain, in patients with neuropathic pain (Mills et al, ), arthritis (Howard et al, ), spinal cord injury (Kaushal et al, ; Min et al, ) and fibromyalgia (Napadow, & Harrisis, ; Schmidt‐Wilcke et al, ) and also in rat pain models with etiology of peripheral neuropathy (Baliki, Chang, Baria, Centeno, & Apkarian, ; Chang et al, ), arthritis (Abaei et al, ) and spinal cord injury (Seminowicz et al, ). Currently, rsfMRI is considered as a useful tool for exploration of pathophysiology of central nervous system (CNS) diseases including pain (Sakoğlu et al, ) and translation between animals and humans (Bajic, Craig, Mongerson, Borsook, & Becerra, ; Pan, Billings, Grooms, Shakil, & Keilholz, ).…”