Abnormal dynamic functional connectivity is linked to recovery after acute ischemic stroke

Human Brain Mapping, Journal Year: 2021, Volume and Issue: 42(7), P. 2278 - 2291

Published: March 2, 2021

The aim of the current study was to explore whole-brain dynamic functional connectivity patterns in acute ischemic stroke (AIS) patients and their relation short long-term severity. We investigated resting-state MRI-based 41 AIS two five days after symptom onset. Re-occurring configurations were obtained using a sliding window approach k-means clustering. evaluated differences between three NIHSS-stroke severity defined groups (mildly, moderately, severely affected patients). Furthermore, we built Bayesian hierarchical models evaluate predictive capacity examine interrelation with clinical measures, such as white matter hyperintensity lesions. Finally, established correlation analyses well 90-day neurological recovery (ΔNIHSS). identified distinct acutely post-stroke. More spent significantly more time configuration that characterized by particularly strong isolated processing brain domains (three-level ANOVA: p < .05, post hoc t tests: FDR-corrected). Configuration-specific estimates possessed addition one measures. Recovery, indexed realized change NIHSS over time, linked bilateral intraparietal lobule left angular gyrus (Pearson's r = -.68, .003, Our findings demonstrate transiently increased information multiple case severe AIS. Dynamic involving default mode network components correlated first 3 months poststroke.

Language: Английский

---

MRI findings in autoimmune encephalitis

Revue Neurologique, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 1, 2024

Language: Английский

---

Functional connectivity dynamics reflect disability and multi-domain clinical impairment in patients with relapsing-remitting multiple sclerosis

NeuroImage Clinical, Journal Year: 2022, Volume and Issue: 36, P. 103203 - 103203

Published: Jan. 1, 2022

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system associated with deficits in cognitive and motor functioning. While structural brain changes such as demyelination are early hallmark disease, a characteristic profile functional alterations MS lacking. Functional neuroimaging studies at various stages have revealed complex heterogeneous patterns aberrant connectivity (FC) MS, previous largely being limited to static account FC. Thus, it remains unclear how time-resolved FC relates variance clinical disability status MS. We here aimed characterize network organization patients analysis explore relationship between status, multi-domain outcomes altered dynamics. Resting-state MRI (rs-fMRI) data were acquired from 101 age- sex-matched healthy controls (HC). Based on Expanded Disability Status Score (EDSS), split into two sub-groups: without (EDSS≤1, n = 36) mild moderate levels (EDSS≥2, 39). Five dynamic states extracted whole-brain rs-fMRI data. Group differences strength, across-state overall connectivity, dwell time, transition frequency, modularity, global assessed. Patients' impairment was quantified custom outcome z-scores (higher: worse) for domains depressive symptoms, fatigue, motor, vision, cognition, total atrophy, lesion load. Correlation analyses measures performed Spearman partial correlation controlling age. Patients exhibited more widespread spatiotemporal pattern spent time high-connectivity, low-occurrence state compared HCs. Worse symptoms all positively EDSS scores. Furthermore, symptom severity related dynamics measured by state-specific DMN attention networks, while fatigue reduced frontoparietal basal ganglia. Despite comparably low we identified distinct those disability, these sensitive multiple domains. uncovered correlations that remained undetected conventional analyses, showing accounting temporal helps disentangle alterations,

Language: Английский

---

Impaired functional connectivity of the hippocampus in translational murine models of NMDA-receptor antibody associated neuropsychiatric pathology

Molecular Psychiatry, Journal Year: 2023, Volume and Issue: 29(1), P. 85 - 96

Published: Oct. 24, 2023

Abstract Decreased hippocampal connectivity and disruption of functional networks are established resting-state MRI (rs-fMRI) features that associated with neuropsychiatric symptom severity in human anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. However, the underlying pathophysiology NMDAR encephalitis remains poorly understood. Application patient-derived monoclonal antibodies against NR1 (GluN1) subunit now allows for translational investigation experimental murine antibody disease models neurodevelopmental disorders. Using rs-fMRI, we studied alterations (1) adult C57BL/6 J mice were intrathecally injected a recombinant over 14 days ( n = 10) (2) newly mouse model utero exposure to (NR1-offspring) at age (2a) 8 weeks 15) (2b) 10 months 14). Adult NR1-antibody showed impaired within left hippocampus compared controls, resembling patterns observed patients. Similarly, NR1-offspring significantly reduced after weeks, was likewise months. We successfully reproduced changes different systems previously Translational application this method combined imaging histopathological framework will allow future studies identify biological mechanisms may eventually facilitate non-invasive monitoring activity treatment responses autoimmune

Language: Английский

---

Reduced resilience of brain state transitions in anti‐N‐methyl‐D‐aspartate receptor encephalitis

European Journal of Neuroscience, Journal Year: 2022, Volume and Issue: 57(3), P. 568 - 579

Published: Dec. 14, 2022

Patients with anti-N-methyl-aspartate receptor (NMDA) encephalitis suffer from a severe neuropsychiatric syndrome, yet most patients show no abnormalities in routine magnetic resonance imaging. In contrast, advanced neuroimaging studies have consistently identified disrupted functional connectivity these patients, recent work suggesting increased volatility of state dynamics. Here, we investigate network dynamics through the spatiotemporal trajectory meta-state transitions, yielding time-resolved account brain exploration anti-NMDA encephalitis. To this end, resting-state imaging data were acquired 73 and age- sex-matched healthy controls. Time-resolved was clustered into meta-states, giving rise to transition graph states as nodes transitions between meta-states weighted, directed edges. Network topology, robustness cost networks compared groups. Transition showed significantly lower local efficiency (t = -2.41, pFDR .029), -2.01, .048) higher leap size 2.18, .037) Furthermore, ratio within-to-between module similarity patients. Importantly, alterations correlated disease severity. Together, findings reveal systematic that is characterized by reduced stability resilience plays clinically relevant role manifestation disease.

Language: Английский

---

The T1-weighted/T2-weighted ratio as a biomarker of anti-NMDA receptor encephalitis

Journal of Neurology Neurosurgery & Psychiatry, Journal Year: 2023, Volume and Issue: unknown, P. jnnp - 332069

Published: Oct. 5, 2023

Background Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis rarely causes visible lesions in conventional MRI, yet advanced imaging detects extensive white matter damage. To improve prognostic capabilities, we evaluate the T1-weighted/T2-weighted (T1w/T2w) ratio, a measure of integrity computable from clinical MRI sequences, NMDAR and examine its associations with cognitive impairment. Methods T1-weighted T2-weighted were acquired cross-sectionally at 3 Tesla 53 patients (81% women, mean age 29 years) matched healthy controls. Quantitative voxel-wise group differences T1w/T2w ratios neuropsychological outcomes assessed. P-values false discovery rate (FDR) adjusted where multiple tests conducted. Results Patients had significantly lower across normal appearing (p=0.009, Hedges’ g=−0.51), which was associated worse verbal episodic memory performance (r=0.39, p=0.005, p(FDR)=0.026). White loss observed corticospinal tract, superior longitudinal fascicle, optic radiation callosal body medium to large effects (Cohen’s d=[0.42–1.17]). In addition, showed decreased hippocampus (p=0.002, p(FDR)=0.005, g=−0.62), amygdala g=−0.63) thalamus (p=0.010, p(FDR)=0.019, g=−0.51). Conclusions The ratio microstructural changes grey that correlate performance. Computable this shows promise bridging clinico-radiological dissociation could serve as an outcome trials.

Language: Английский

---

Hippocampal hub failure is linked to long-term memory impairment in anti-NMDA-receptor encephalitis: insights from structural connectome graph theoretical network analysis

Journal of Neurology, Journal Year: 2024, Volume and Issue: 271(9), P. 5886 - 5898

Published: July 8, 2024

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is characterized by distinct structural and functional brain alterations, predominantly affecting the medial temporal lobes hippocampus. Structural connectome analysis with graph-based investigations of network properties allows for an in-depth characterization global local changes their relationship clinical deficits in NMDAR encephalitis.

Language: Английский

---

Functional connectivity changes of the hippocampal subregions in anti-N-methyl-D-aspartate receptor encephalitis

Brain Imaging and Behavior, Journal Year: 2024, Volume and Issue: 18(3), P. 686 - 697

Published: Feb. 16, 2024

Language: Английский

---

Eigenvector centrality mapping reveals volatility of functional brain dynamics in anti-NMDA receptor encephalitis

Biological Psychiatry Cognitive Neuroscience and Neuroimaging, Journal Year: 2024, Volume and Issue: 9(11), P. 1222 - 1229

Published: July 27, 2024

Anti-N-methyl-D-aspartate receptor encephalitis (NMDARE) causes long-lasting cognitive deficits associated with altered functional connectivity. Eigenvector centrality (EC) mapping represents a powerful new method for data-driven voxel-wise and time-resolved estimation of network importance – beyond changes in classical 'static' To assess brain organization, we applied EC 73 patients NMDARE matched healthy controls. Areas significant group differences were further investigated using (i) spatial clustering analyses, (ii) time series correlation to synchronicity between the hippocampus cortical regions, (iii) clinical parameters. Dynamic, showed significantly higher variability 13 areas (p(FWE)<0.05) compared HC. dynamic spatially organized clusters resembling resting-state networks. Importantly, frontotemporal cluster was impaired verbal episodic memory (r=-0.25, p=0.037). medial prefrontal cortex reduced HC (p(FWE)<0.05, t(max)=3.76), (r=0.28, p=0.019). Static analyses only one region (left intracalcarine cortex). Widespread dynamics hippocampal-medial may thus represent neural correlate dysfunction NMDARE. detected substantially more alterations than traditional static approaches, highlighting potential this explain long-term

Language: Английский

---

Hippocampal hub failure is linked to long-term memory impairment in anti-NMDA-receptor encephalitis - Insights from structural connectome graph theoretical network analysis

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Aug. 21, 2023

Abstract Introduction Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is characterized by distinct structural and functional brain alterations, predominantly affecting the medial temporal lobes hippocampus. Structural connectome analysis with graph-based investigations of network properties allows for an in-depth characterization global local changes their relationship clinical deficits in NMDAR encephalitis. Objective To investigate connectivity efficiency use probabilistic whole-brain tractography graph theoretical networks. Methods networks from sixty-one patients post-acute stage (median time acute hospital discharge: 18 months) age- sex-matched healthy controls (HC) were analyzed using diffusion-weighted imaging (DWI)-based anatomically-constrained spherical deconvolution-informed filtering tractograms. We calculated global, modular, nodal measures indicative reorganization special focus on default-mode network, lobe, Pathologically altered metrics included multiple regression analyses to potential association course, disease severity, cognitive outcome. Results Patients showed regular metrics, but bilateral reductions hippocampal node strength (left: p =0.049; right: =0.013) increased right precuneus ( compared HC. Betweenness centrality was decreased left-sided entorhinal cortex =0.042) left caudal middle frontal gyrus (p = 0.037). Correlation a significant between reduced verbal long-term memory impairment =0.021) Conclusion Focal property indicate hub failure that associated at stage, while remain unaltered. Graph theory provides new pathophysiological insight into persistent

Language: Английский

---