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| 2021 | Dynamic changes in functional network connectivity involving amyotrophic lateral sclerosis and its correlation with disease severity | Chen et al., 2021 [59] | 32 ALS and 45 controls | sMRI and fMRI: Independent component analysis and dynamic functional network connectivity dFNC | ALS patients showed increased dFNC between DMN and SMN. |
| | Functional and structural impairment of transcallosal motor fibers in ALS: a study using transcranial magnetic stimulation, diffusion tensor imaging, and diffusion-weighted spectroscopy | Hübers et al., 2021 [8] | 27 ALS and 21 controls | DTI and TMS: Fractional anisotropy (FA) interhemispheric inhibition (IHI) | ALS patients showed significantly decreased FA in the motor segment of the corpus callosum), and IHI was significantly reduced compared to controls. |
| | Segmental involvement of the corpus callosum in C9orf72-associated ALS: a Tract of interest-based DTI study | Müller et al., 2021 [18] | 25 ALS and 25 controls | DTI: Tractwise fractional anisotropy statistics (TFAS) | Regional FA reduction for tracts of the Calloway areas II and III for ALS patients with C9orf72. |
| | Ultra-high field (7T) functional magnetic resonance imaging in amyotrophic lateral sclerosis: a Pilot study | Barry et al., 2021 [52] | 12 ALS and 9 controls | sMRI and fMRI: | Reduced functional connectivity between the superior sensorimotor cortex and bilateral cerebellar lobule VI in ALS patients. |
| 2020 | Electrical and hemodynamic Neural Functions in People with ALS: an EEG-fNIRS resting-state study | Deligani et al., 2020 [64] | 10 ALS and 9 controls | EEG and fNIRS: Connectivity study | Increased frontoparietal EEG connectivity in the alpha and beta bands and increased interhemispheric and right intrahemispheric fNIRS connectivity in the frontal and prefrontal regions were observed in ALS. Frontal, central, and temporal theta and alpha EEG power decreased in ALS, as did parietal and occipital alpha EEG power, while frontal and parietal hemodynamic spectral power increased in ALS. |
| | Frontal functional network disruption associated with amyotrophic lateral sclerosis: an fNIRS-based minimum spanning tree analysis | Borgheal et al., 2020 [65] | 9 ALS and 10 controls | fNIRS: MST network analysis | Results showed significant between-group differences in several MST topological properties, including leaf fraction, maximum degree, diameter, eccentricity, and degree divergence. |
| | Multimodal longitudinal study of structural brain involvement in amyotrophic lateral sclerosis | van der Burgh et al., 2020 [38] | 298 ALS and 156 controls | sMRI and DTI: cortical thickness, subcortical volumes, and white matter connectivity | Patients with a C9orf72 mutation showed widespread gray and white matter involvement at baseline and extensive loss of white matter integrity in the connectome over time. In C9orf72-negative patients, there was cortical thinning of motor and frontotemporal regions and loss of white matter integrity of connections linked to the motor cortex. |
| | Progression of brain functional connectivity and frontal cognitive dysfunction in ALS | Castelnovo et al., 2020 [70] | 25 ALS longitudinal | FMRI: Resting-state functional connectivity changes | After six months, ALS patients showed an increased rsFC of the left anterior cingulate, left middle frontal gyrus (MFG), and left superior frontal gyrus within the frontostriatal network, left MFG, left supramarginal gyrus, and right angular gyrus within the left frontoparietal network. |
| | Regional callosal integrity and bilaterality of limb weakness in amyotrophic lateral sclerosis | Tu et al., 2020 [33] | 29 ALS and 25 controls | DTI: Probabilistic tractography of the corpus callosum | In the combined patient group, the most prominent differences in diffusivity metrics were in the rostral body, posterior midbody, and isthmus of the corpus callosum. Loss of corpus callosum integrity was most prominent in the subgroup with unilateral limb weakness at the time of scanning. |
| | Resting-state functional connectivity is decreased globally across the C9orf72 mutation spectrum | Smallwood et al., 2020 [43] | 25 ALS and 26 controls | FMRI: Graph theory analysis | Both global and connection-specific decreases in resting-state connectivity were observed, with no substantial reorganization of network hubs. |
| | Resting-state functional MRI brain signatures of fast disease progression in amyotrophic lateral sclerosis: a retrospective study | Trojsi et al., 2020 [51] | 54 ALS and 22 controls | sMRI, DTI, and FMRI: | ALS patients showed reduced functional connectivity in both motor and extramotor networks. |
| | Structural and functional brain connectome in motor neuron diseases: a multicenter MRI study | Basia et a. 2020 [40] | 179 ALS and 79 controls | sMRI, FMRI, and DTI: Connectivity and graph analysis | ALS and patients with PLS showed altered structural global network properties, as well as local topologic alterations and decreased structural connectivity in sensorimotor, basal ganglia, frontal, and parietal areas. |
| | Hippocampal connectivity in amyotrophic lateral sclerosis (ALS): more than Papez circuit impairment | Trojsi et al., 2020 [47] | 32 ALS and 21 controls | fMRI and DTI: Seed-based connectivity (SBC), voxel-based morphometry (VBM), and tract-based spatial statistics (TBSS) | Decreased functional connectivity between bilateral hippocampus, bilateral parahippocampal gyri and cerebellum in ALS patients compared with HCs. |
| | Involvement of the dentate nucleus in the pathophysiology of amyotrophic lateral sclerosis: a multicenter and multimodal neuroimaging study | Bharti et al., 2020 [85] | 71 ALS and 56 controls | sMRI, fMRI, and DTI: Seed- and RO-based connectivity and volumetric analysis | DN rsFC was reduced with cerebrum (supplementary motor area, precentral gyrus, frontal, posterior parietal, and temporal), lobule IV, and brain stem, and increased with the parieto-occipital region. |
| 2019 | Abnormal topological organization of structural covariance networks in amyotrophic lateral sclerosis | Zhang et al., 2019 [86] | 60 ALS patients and 60 controls | sMRI: Structural covariance networks were studied in ALS patients and control subjects | Structural covariance networks of ALS patients showed an increased path length, clustering coefficient, small world index, and modularity, as well as decreased global efficiency and increased local segregation. Locally, ALS patients showed decreased nodal degree and betweenness in the gyrus rectus and/or Heschl’s gyrus and increased betweenness in the supplementary motor area, triangular part of the inferior frontal gyrus, supramarginal gyrus, and posterior cingulate cortex. In addition, in ALS patients, there were more frontal and subcortical hubs than in normal controls. |
| | Characteristic increases in EEG connectivity correlate with changes of structural MRI in amyotrophic lateral sclerosis | Nasseroleslami et al., 2019 [87] | 100 ALS and 34 controls | EEG + sMRi: EEG connectivity | Increased EEG coherence between parietal-frontal scalp regions (in γ-band) and between bilateral regions over motor areas (in θ-band). |
| | Patterned functional network disruption in amyotrophic lateral sclerosis | Dukic et al., 2019 [66] | 74 ALS and 47 controls | EEG: Functional connectivity using beamformer source analysis | Decreased spectral power in the occipital and temporal (δ- to β-band), lateral/orbitofrontal (δ- to θ-band) and sensorimotor (β-band) regions of the brain in patients with ALS. Furthermore, we show increased comodulation of neural oscillations in the central and posterior (δ-, θ-, and γl-band) and frontal (δ- and γl-band) regions, as well as decreased synchrony in the temporal and frontal (δ- to β-band) and sensorimotor (β-band) regions. |
| | Precentral degeneration and cerebellar compensation in amyotrophic lateral sclerosis: a multimodal MRI analysis | Qiu et al., 2019 [11] | 60 ALS and 60 controls | sMRI, fMRI, and DTI: Gray matter volume (GMV), white matter FA, and functional connectivity (FC) | Compared with healthy controls, patients with ALS showed decreased GMV in the left precentral gyrus and increased GMV in bilateral cerebellum, decreased FA in the left corticospinal tract and body of corpus callosum, and decreased FC in multiple brain regions, involving bilateral postcentral gyrus, precentral gyrus, and cerebellum anterior lobe, among others. |
| | Regional dynamics of the resting brain in amyotrophic lateral sclerosis using fractional amplitude of low-frequency fluctuations and regional homogeneity analyses | Bueno et al., 2019 [88] | 20 ALS and 11 controls | fMRI: fractional amplitude of low-frequency fluctuations (fALFF) and regional homogeneity (ReHo) | Decreased fALFF and ReHO in ALS patients compared with HC in widespread cortical regions including motor and sensory regions. |
| | Structural connectivity alterations in amyotrophic lateral sclerosis: a graph theory-based imaging study | Fortainer et al., 2019 [77] | 25 ALS and 26 controls | DTI: Structural connectivity | Patients with ALS exhibited global network alterations with decreased global efficiency (Eglob; p = 0.03) and a trend of the reduced whole-brain mean degree (p = 0.05) compared to controls. |
| 2018 | Abnormal functional connectivity density in amyotrophic lateral sclerosis | Li et al., 2018 [44] | 38 ALS and 35 controls | fMRI: Functional connectivity density mapping (FCDM), an ultrafast data-driven method, that quantifies functional connections between a given voxel and all the other voxels in the entire brain | Patients with ALS were found to have decreased short-range FCD in the primary motor cortex and increased long-range FCD in the premotor cortex. |
| | Brain functional networks become more connected as amyotrophic lateral sclerosis progresses: a source level magnetoencephalographic study | Sorrentino et al., 2018 [67] | 54 ALS and 25 controls | MEG: Betweenness centrality | The more advanced the disease, the more connected, scale-free, and disassortative the brain networks. |
| | Fast progressive lower motor neuron disease is an ALS variant: a two-centre tract of interest-based MRI data analysis | Müller et al., 2018 [35] | 65 LMND, 92 controls, and 101 ALS | DTI: Fractional anisotropy maps and voxel-based comparison | Characteristic alteration patterns along the CST and also in frontal and prefrontal brain areas in LMND patients compared to controls and ALS. Fast progressing LMND showed substantial involvement, like in ALS, while slow progressors showed less severe alterations. FA of CST is affected in LMND just like ALS. |
| | Increased cerebral functional connectivity in ALS: a resting-state magnetoencephalography study | Proudfoot et al., 2018 [53] | 24 ALS, 24 controls, 9 PLS, and 15 carriers | MEG: Power fluctuations in neuronal oscillation from distributed cortical parcels | Increased functional connectivity, particularly from the posterior cingulate cortex, was demonstrated in both patient groups compared to healthy controls. |
| | Monitoring value of multimodal magnetic resonance imaging in disease progression of amyotrophic lateral sclerosis: a prospective observational study | Shen et al., 2018 [89] | 10 ALS longitudinal | sMRI, fMRI, DWI, and ASL: Multimodal imaging | Functional connectivity was increased in the motor areas (fALFF of the right precentral gyri and superior frontal gyri, and ReHo of right precentral gyri) and decreased in the extramotor areas. |
| | Regional thalamic MRI as a marker of widespread cortical pathology and progressive frontotemporal involvement in amyotrophic lateral sclerosis | Tu et al., 2018 [34] | 20 ALS and 31 controls | DTI: Diffusion tractography to parcellate the thalamus | Widespread diffusivity alterations in motor and extramotor associated thalamic parcellations. |
| | The two-year progression of structural and functional cerebral MRI in amyotrophic lateral sclerosis | Menke et al., 2018 [90] | 16 ALS longitudinal | sMRI, DTI, and FMRI: VBM and independent component analysis (ICA) | Widespread and progressive reductions in gray matter were observed in the precentral gyri and posterior cingulate cortex, as well as progressive local atrophy of the thalamus, caudate, and pallidum bilaterally, and right putamen, hippocampus, and amygdala. The most prominent DTI tract-based changes were in the superior longitudinal fasciculus and corpus callosum. FC decreases were noted between the sensorimotor resting-state network and the frontal pole, between a network comprising both thalami and an area in the visual cortex. |
| | Unraveling ALS due to SOD1 mutation through the combination of brain and cervical cord MRI | Agosta et al., 2018 [39] | 31 ALS and 33 controls. | sMRI, fMRI, DTI: Cortical thickness analysis, diffusion tensor MRI of the corticospinal tracts (CST) and corpus callosum, and resting-state functional connectivity | Fractional anisotropy showed that sporadic ALS patients had significant CST damage relative to both healthy controls and SOD1-related ALS although the latter showed alterations that were intermediate between controls and sporadic ALS. Functional hyperconnectivity of the motor cortex in the sensorimotor network was observed in patients with sporadic ALS relative to controls. |
| 2017 | Aberrant interhemispheric homotopic functional and structural connectivity in amyotrophic lateral sclerosis | Zhang et al., 2017 [46] | 38 ALS and 35 controls. | fMRI and DTRI: Voxel mirrored homotopic connectivity (VMHC) and probabilistic fiber tracking that quantifies functional connectivity between each voxel in one hemisphere and its mirrored counterpart in the opposite hemisphere | Extensive reductions of VMHC associated with ALS in brain regions of the precentral and postcentral gyrus, the paracentral lobule, the superior temporal gyrus, the middle cingulate gyrus, the putamen, and the superior parietal lobules. With DTI, the analysis has also revealed reductions of interhemispheric structural connectivity through the CC subregions II, III, and V in patients with ALS. Additionally, interhemispheric functional connectivity of the bilateral precentral gyri positively correlated with fractional anisotropy values of the CC subregion III, which structurally connects the bilateral motor cortices. |
| | Brain functional connectome abnormalities in amyotrophic lateral sclerosis are associated with disability and cortical hyperexcitability | Geevasinga et al., 2017 [72] | 20 ALS and 20 controls | sMRI, fMRI and TMS: Using threshold tracking transcranial magnetic stimulation (TMS) and functional connectivity | Increased functional connectivity in 12 network edges connecting 14 nodes. Connectivity changes in frontal regions are inversely correlated with functional disability. The mean clustering coefficient was significantly increased in patients with ALS. |
| | Frequency-specific abnormalities of Intrinsic functional connectivity strength among patients with amyotrophic lateral sclerosis: a resting-state fMRI study | Li et al., 2017 [91] | 21 ALS and 21 controls | fMRI: Functional connectivity strength (FCS) | ALS patients showed a significantly decreased FCS in the left prefrontal cortex (PFC) and the bilateral superior frontal gyrus. FCS changes in ALS were widespread and frequency-dependent. |
| | Resting-state fMRI correlates of theory of mind impairment in amyotrophic lateral sclerosis | Trojsi et al., 2017 [50] | 21 ALS and 15 controls | fMRI: Resting-state connectivity | Decreased connectivity in frontotemporal areas within the main cognitive resting-state networks, including the default mode (DMN), the right and left frontoparietal (R-, L-FPN), and the salience (SLN) networks, in the entire ALS group. |
| | White matter structural network abnormalities underlie executive dysfunction in amyotrophic lateral sclerosis | Dimond et al., 2017 [22] | 18 ALS and 22 controls | DTI: Tract-based statistics | ALS cognitive impaired patients displayed altered local connectivity and structural integrity in these same frontal regions that correlated with executive dysfunction. |
| 2016 | A large-scale multicenter cerebral diffusion tensor imaging study in amyotrophic lateral sclerosis | Müller et al., 2016 [92] | 253 ALS and 189 controls | DTI study: Fractional anisotropy (FA) maps were used | Significant difference in CST, frontal lobe, brainstem, and hippocampus in ALS patients. These changes correlated with the postmortem neuropathologic changes. |
| | Corticoefferent pathways in pure lower motor neuron disease: a diffusion tensor imaging study | Rosenbohm et al., 2016 [31] | 37 LMND and 53 controls | DTI: FA, AD, RD, MC, diffusion tractography, and whole-brain spatial statistics | The analysis demonstrated widespread and characteristic patterns of alterations in patients with LMND, predominantly along the corticospinal tract (CST), with multiple clusters of regional FA reductions. |
| | Disrupted effective connectivity of the sensorimotor network in amyotrophic lateral sclerosis | Fang et al., 2016 [27] | 20 ALS patients and 21 controls | fMRI: Dynamic causal modeling analysis | In ALS patients, significant regional activity alterations in the left primary motor cortex (M1), the left primary somatosensory cortex (S1) and the right supplementary motor cortex (SMA) are found. Among these regions, spectral DCM revealed a missing closed-loop circuit between the left M1 and the right SMA and lost projection from the right SMA to the left S1 in ALS. |
| | EEG functional network topology is associated with disability in patients with amyotrophic lateral sclerosis | Fraschini et al., 2016 [69] | 21 ALS and 16 controls | EEG: Functional connectivity using the phase lag index (PLI) and network topology using the minimum spanning tree (MST) | No significant group differences were observed for the global mean PLI in any frequency band. A significant MST dissimilarity between ALS patients and healthy controls was found in the beta band. |
| | Functional connectivity changes resemble patterns of pTDP-43 pathology in amyotrophic lateral sclerosis | Schulthess et al., 2016 [55] | 135 ALS and 56 controls | fMRI and DTI | Functional connectivity patterns associated with the motor, brainstem, ventral attention, and default mode/hippocampal intrinsic connectivity network revealed increased connectivity maps in ALS patients. |
| | Increased functional connectivity common to symptomatic amyotrophic lateral sclerosis and those at genetic risk | Menke et al., 2016 [57] | 12 ALS and 12 controls | sMRI, fMRI, and DWI: Cortical thickness analysis, voxel-based morphometry, volumetric and shape analyses of subcortical structures, tract-based spatial statistics of metrics derived from the diffusion tensor, and resting-state functional connectivity (FC) analyses were performed | Gray matter cortical thickness and shape analysis revealed significant atrophy in patients with ALS (but not psALS) compared with controls in the right primary motor cortex and right caudate. Comparison of diffusion tensor metrics showed widespread fractional anisotropy and radial diffusivity differences in patients with ALS compared to controls and the psALS group, encompassing parts of the corpus callosum, corticospinal tracts, and superior longitudinal fasciculus. While FC in the resting-state sensorimotor network was similar in psALS and controls, FC between the cerebellum and a network comprising the precuneus, cingulated, and middle frontal lobe was significantly higher in psALS and affected ALS compared to controls. |
| | Investigating default mode and sensorimotor network connectivity in amyotrophic lateral sclerosis | Chenji et al., 2016 [74] | 21 ALS and 40 controls | fMRI: Compared to default mode networks and sensorimotor networks | Significant group differences in resting-state networks between patients and controls were absent, as was the dependence on the degree of UMN burden. However, DMN connectivity was increased in patients with greater disability and faster progression rate, and SMN connectivity was reduced in those with greater motor impairment. |
| | Occipital cortical gyrification reductions associate with decreased functional connectivity in amyotrophic lateral sclerosis | Zhang et al., 2016 [49] | 25 ALS and 25 controls. | sMRI and fMRI: Surface-based local gyrification index (LGI) and seed-based functional connectivity | ALS patients had significantly reduced LGI in the right occipital cortex, and that abnormality in this region was associated with decreased functional connectivity in the bilateral precuneus. |
| | Widespread temporo-occipital lobe dysfunction in amyotrophic lateral sclerosis | Loawe et al., 2016 [41] | 64 ALS and 38 controls | FMRI: whole-brain functional connectivity graph analysis | Clusters of reduced functional connectivity were observed in the sensorimotor cortex. |
| 2015 | Altered cortical hubs in functional brain networks in amyotrophic lateral sclerosis | Ma et al., 2015 [76] | 20 ALS and 20 HC | fMRI: Functional connectivity strength (FCS) | High FCS hubs in the prefrontal cortex in ALS versus healthy controls. |
| | Cerebro-cerebellar connectivity is increased in primary lateral sclerosis | Meoded et al., 2015 [73] | 16 PLS patients and 14 controls | fMRI and DTI: Structural and functional connectivity | PLS patients had 12 regions of increased functional connectivity. |
| | Functional connectivity changes in resting-state EEG as potential biomarker for amyotrophic lateral sclerosis | Iyer et al., 2015 [68] | 18 ALS and 17 controls | EEG: Graph theory measures | Cross spectral density in the alpha band was higher in patients. In ALS patients, increased degree values of the network nodes were noted in the central and frontal regions in the theta band across seven of the different connectivity maps, among patients, the clustering coefficient in alpha and gamma bands was increased in all regions of the scalp and connectivity were significantly increased (p = 0.02). The nodal network showed increased assortativity in the alpha band in the patients group. The clustering coefficient in partial directed connectivity (PDC) showed significantly higher values for patients in alpha, beta, gamma, theta, and delta frequencies. |
| | Metabolic spatial connectivity in amyotrophic lateral sclerosis as revealed by independent component analysis | Pagani et al., 2015 [28] | 259 ALS and 40 controls. | PET: Spatial ICA | Eight components were selected as pathophysiologically meaningful discriminated patients from controls with 99.0% accuracy. |
| | Reduced structural connectivity within a prefrontal-motor-subcortical network in amyotrophic lateral sclerosis | Buchanan et al., 2015 [32] | 30 ALS and 30 controls | sMRI and DTI: Network-based statistics | Impaired motor-frontal-subcortical subnetwork (10 nodes and 12 bidirectional connections), consistent with upper motor neuron pathology. Reduced FA in three of the impaired network connections. |
| 2014 | Additional resources and the default mode network: evidence of increased connectivity and decreased white matter integrity in amyotrophic lateral sclerosis | Heimrath et al., 2014 [75] | 9 ALS patients and 11 controls | fMRI and DTI: Study focused on verbal fluency and attention and the relationship with functional connectivity in the DMN and white matter integrity | Patients showed increased functional connectivity in parahippocampal and parietal areas of the non-task-associated DMN compared to controls. The more pronounced the cognitive deficits, the stronger the increase in functional connectivity in those areas. White matter integrity was reduced in frontal areas in the patients. In conclusion, increased connectivity in the DMN in parahippocampal and parietal areas might represent the recruitment of accessory brain regions to compensate for dysfunctional frontal networks. |
| | Correlation between structural and functional connectivity impairment in amyotrophic lateral sclerosis | Schmidt et al., 2014 [45] | 64 ALS and 27 controls | sMRI, DWI, and fMRI | (i) The most structurally affected connections considerably overlap with the most functionally impaired connections; (ii) direct connections of the motor cortex are both structurally and functionally more affected than connections at a greater topological distance from the motor cortex; and (iii) there is a strong positive correlation between changes in SC and FC averaged per brain region (r50.44, P < 0.0001). |
| | Structural brain network imaging shows expanding disconnection of the motor system in amyotrophic lateral sclerosis | Verstraete et al., 2014 [21] | 24 ALS and 22 controls | DTI: Whole-brain tractography | Demonstrated an expanding subnetwork of affected brain connections over time with a central role for the primary motor regions. |
| 2013 | Altered motor network functional connectivity in amyotrophic lateral sclerosis: a resting-state functional magnetic resonance imaging study | Zhou et al., 2013 [93] | 12 ALS patients and 12 controls | fMRI: Functional connectivity (FC) of motor cortex | Both decreased and increased within-motor network FC in ALS patients. Increased FC between the bilateral superior parietal lobule and the right anterior inferior cerebellum was found to be correlated with disease severity, with higher FC related to more severe disease. |
| | Divergent brain network connectivity in amyotrophic lateral sclerosis | Agosta et al., 2013 [42] | 20 ALS and 15 controls | fMRI: Independent component analysis | ALS patients showed a decreased connectivity of the right orbitofrontal cortex and enhanced connectivity of the left precuneus in the default mode network; a decreased connectivity of the left inferior frontal cortex and increased connectivity of the right angular gyrus in the right frontoparietal network; and increased connectivity of the parietal cortex in the left frontoparietal network. |
| | Dysfunctions within limbic-motor networks in amyotrophic lateral sclerosis | Passmonti et al., 2013 [60] | 11 ALS and 12 HC | fMRI: fMRI task analysis | ALS patients had greater activation in the PFC areas and altered left amygdala PFC connectivity. |
| | Multiple kernel learning captures a systems-level functional connectivity biomarker signature in amyotrophic lateral sclerosis | Feket et al., 2013 [48] | 40 ALS and 30 controls | fMRI: Intra- and intermotor functional network analysis | ALS patients had reduced connectivity of both the cortical and subcortical motor areas with non-motor areas, reduced subcortical-cortical motor connectivity, and increased connectivity observed within subcortical motor networks. |
| | The utility of independent component analysis and machine learning in the identification of the amyotrophic lateral sclerosis diseased brain | Welsh et al., 2013 [29] | 32 ALS and 31 controls | fMRI: ICA analysis and support vector machine (SVM) machine learning analysis | Over 71% accuracy for disease state classification is obtained. |
| 2012 | Direct evidence of intra- and interhemispheric corticomotor network degeneration in amyotrophic lateral sclerosis: an automated MRI structural connectivity study | Rose et al., 2012 [20] | 15 ALS and 15 HC | sMRI and DWI: Whole-brain diffusion tractography | Significant reduction in mean FA within a number of intra- and interhemispheric motor pathways in ALS patients is noted. |
| 2011 | Impaired structural motor connectome in amyotrophic lateral sclerosis | Verstraete et al., 2011 [37] | 35 ALS and 19 controls | sMRI and DTI: Fiber tracking and network analysis | ALS patient had impaired subnetwork of regions with reduced white matter connectivity around primary motor regions (bilateral precentral gyrus and right paracentral lobule), including secondary motor regions (bilateral caudal middle frontal gyrus and pallidum) as well as high-order hub regions (right posterior cingulate and precuneus). In addition, a significant reduction in overall efficiency and clustering is noted. |
| | Sensorimotor functional connectivity changes in amyotrophic lateral sclerosis | Agosta et al., 2011 [58] | 26 ALS and 15 controls | fMRI: Resting functional connectivity analysis | ALS patients versus controls showed a significantly increased functional connectivity between the left SMC and the right cingulate cortex, parahippocampal gyrus, and cerebellum-crus II. |
| 2010 | Motor network degeneration in amyotrophic lateral sclerosis: a structural and functional connectivity study | Verstaete et al., 2010 [56] | 12 ALS and 12 controls | sMRI, DTI, and fMRI: Whole-brain cortical thickness and diffusion tensor imaging (DTI) of crucial motor tracts and functional connectivity analysis of the motor network based on resting-state fMRI | Functional organization of the motor network was unchanged in patients with ALS compared to healthy controls; however, the level of functional connectedness was significantly correlated with disease progression rate. Patients with increased connectedness had progressive disease courses. |
| 2006 | Probabilistic diffusion tractography: a potential tool to assess the rate of disease progression in amyotrophic lateral sclerosis | Ciccarelli et al., 2006 [36] | 13 ALS and 19 controls | DTI: Probabilistic tractography, FA analysis of connectivity along CST, and disease progression rate | Patients with rapid progression had a significantly lower mean FA. |
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