Reorganization and Plasticity of the Language Network in Patients with Cerebral Gliomas

NeuroImage Clinical, Journal Year: 2023, Volume and Issue: 37, P. 103326 - 103326

Published: Jan. 1, 2023

Language is organized in large-scale networks the human brain that show a strong potential for flexible interactions and adaptation. Neuroplasticity central mechanism allows such dynamic modulation to changing conditions across life span particularly important network reorganization after lesions. Most studies on language focused recovery stroke. Yet, degree of adaptive neuroplasticity can also be observed patients with tumors language-eloquent areas. This review discusses key mechanisms neural tumors. Our main aim elucidate underlying intra- interhemispheric plasticity these patients. The following patterns are discussed: 1) Persisting function within tumor; 2) Reorganization perilesional regions; 3) distributed affected hemisphere; 4) contralesional hemisphere. In this context, we shed light language-related frontal temporo-parietal areas discuss their functional relevance. We address tumor-related changes structural connectivity between eloquent regions. Thereby, expand general understanding plastic facilitate clinical decision-making processes effective, function-preserving tumor treatment.

Language: Английский

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Brain Functional Connectivity in Low- and High-Grade Gliomas: Differences in Network Dynamics Associated with Tumor Grade and Location

Cancers, Journal Year: 2022, Volume and Issue: 14(14), P. 3327 - 3327

Published: July 8, 2022

Brain tumors lead to modifications of brain networks. Graph theory plays an important role in clarifying the principles connectivity. Our objective was investigate network related tumor grade and location using resting-state functional magnetic resonance imaging (fMRI) graph theory. We retrospectively studied 30 low-grade (LGG), high-grade (HGG) left-hemispheric glioma patients 20 healthy controls (HC) with rs-fMRI. Tumor labeled as: frontal, temporal, parietal, insular or occipital. collected patients’ clinical data from records. analyzed whole-brain hemispheric networks all HC. Subsequently, we lobar subgroups divided by location. Seven graph-theoretical metrics were calculated (FDR p < 0.05). Connectograms computed for significant nodes. The two-tailed Student t-test Mann−Whitney U-test (p 0.05) used compare data. analysis showed increased ipsilateral connectivity LGG (global efficiency = 0.03) decreased contralateral HGG (degree/cost 0.028). Frontal temporal bilateral modifications; parietal only local effects. Temporal led a decrease metrics. influence pattern reorganization. may show more favorable changes than HGG, reflecting fewer deficits.

Language: Английский

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Functional MRI in Neuro-Oncology: State of the Art and Future Directions

Radiology, Journal Year: 2023, Volume and Issue: 308(3)

Published: Sept. 1, 2023

Since its discovery in the early 1990s, functional MRI (fMRI) has been used to study human brain function. One well-established application of fMRI clinical setting is neurosurgical planning patients with tumors near eloquent cortical areas. Clinical aims preoperatively identify cortices that serve essential functions daily life, such as hand movement and language. The primary goal neurosurgery maximize tumor resection while sparing adjacent tumor. When a lesion presents vicinity an cortex, surgeons may use plan their best surgical approach by determining proximity regions activation, providing guidance for awake surgery intraoperative mapping. acquisition requires patient preparation prior imaging, determination paradigms, monitoring performance, both processing analysis images. Interpretation maps strong understanding neuroanatomy familiarity technical limitations frequently present including neurovascular uncoupling, compliance, data analysis. This review discusses neuro-oncology, relevant ongoing research topics, prospective future developments this exciting discipline.

Language: Английский

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Language Network Dysfunction and Formal Thought Disorder in Schizophrenia

Schizophrenia Bulletin, Journal Year: 2022, Volume and Issue: 49(2), P. 486 - 497

Published: Oct. 28, 2022

Pathophysiological inquiries into schizophrenia require a consideration of one its most defining features: disorganization and impoverishment in verbal behavior. This feature, often captured using the term Formal Thought Disorder (FTD), still remains to be poorly understood understudied dimensions schizophrenia. In particular, large-scale network level dysfunction that contributes FTD obscure date.

Language: Английский

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Technical Aspects of Motor and Language Mapping in Glioma Patients

Cancers, Journal Year: 2023, Volume and Issue: 15(7), P. 2173 - 2173

Published: April 6, 2023

Gliomas are infiltrative primary brain tumors that often invade functional cortical and subcortical regions, they mandate individualized mapping strategies to avoid postoperative neurological deficits. It is well known maximal safe resection significantly improves survival, while deficits minimize the benefits associated with aggressive resections diminish patients’ quality of life. Although non-invasive imaging tools serve as useful adjuncts, intraoperative stimulation (ISM) gold standard for identifying regions minimizing morbidity during these challenging resections. Current methods rely on use low-frequency high-frequency stimulation, delivered monopolar or bipolar probes either directly surface white matter structures. Stimulation effects can be monitored through patient responses awake procedures and/or motor-evoked somatosensory-evoked potentials in patients who asleep. Depending patient’s preoperative status tumor location size, neurosurgeons may choose employ asleep craniotomies, both which have their own challenges. Regardless method used, goal identify areas non-functional tissue safely removed facilitate an approach trajectory equator, center, tumor. Recent technological advances improved ISM’s utility structures minimized seizure risk stimulation. In this review, we summarize salient technical aspects should aware order implement effectively glioma surgery.

Language: Английский

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Natural rhythmic speech activates network reorganization with frontal community enhancing communication efficiency in patients with intrinsic brain tumor

NeuroImage, Journal Year: 2025, Volume and Issue: 310, P. 121112 - 121112

Published: March 4, 2025

Brain tumors provide unique insights into brain plasticity due to their slow growth compared acute cerebrovascular diseases. Despite relying on sophisticated functional networks, patients with exhibit minimal deficits in higher language functions and demonstrate positive post-injury plasticity; however, the underlying neural mechanisms remain unclear. We utilized high-density electroencephalography investigate network tumor without evident deficits. Natural rhythmic sentences non-rhythmic contrasting speech prosodic harmony were employed examine impact of task integrativeness reorganization. Our study reveals that perception, characterized by processing integrativeness, induced inhibited engagement frontal lobe but evoked enhanced hubness modularity, which supported generation new connections promoted efficiency global connectivity. Furthermore, local invasion prompted adjacent hubs generate enriched during early phase, facilitating later findings underscore significant role reveal importance highly integrated tasks for reorganization rehabilitation.

Language: Английский

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A comparison of diffusion tensor imaging tractography approaches to identify the Frontal Aslant Tract in neurosurgical patients

Frontiers in Neuroscience, Journal Year: 2025, Volume and Issue: 19

Published: April 28, 2025

Introduction This study aims to present various tractography methods for delineating the Frontal Aslant Tract (FAT) and quantify morphological features of FAT based on diffusion tensor imaging. Methods The includes 68 patients, which was reconstructed using Region Of Interest (ROI)-based approach. ROIs were defined in either SFG – Superior Gyrus (ROI 1), or SMA—Supplementary Motor Area 2). respective endpoints located Inferior (IFG)—either pars opercularis triangularis. For each patient, delineated four combinations above ROI–endpoint pairs. Results highest streamline counts fiber volumes obtained ROI 1 (i.e., SFG) with endpoint IFG opercularis. All subjects expressed left dominance pathway quantified by higher regardless gender. Additionally, Mean Diffusivity (MD) lower Fractional Anisotropy (FA) values observed patients 55 years age than younger patients. Discussion is a neural that can be tracked anatomical landmarks. Clinically, it appears between region optimal, as directly associated number fibers greatest volume tract contained these points.

Language: Английский

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Language reorganization in patients with left-hemispheric gliomas is associated with increased cortical volume in language-related areas and in the default mode network

Cortex, Journal Year: 2022, Volume and Issue: 157, P. 245 - 255

Published: Oct. 19, 2022

Language: Английский

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Effect of tumor genetics, pathology, and location on fMRI of language reorganization in brain tumor patients

European Radiology, Journal Year: 2023, Volume and Issue: 33(9), P. 6069 - 6078

Published: April 19, 2023

Abstract Objectives Language reorganization may follow tumor invasion of the dominant hemisphere. Tumor location, grade, and genetics influence communication between eloquent areas growth dynamics, which are drivers language plasticity. We evaluated tumor-induced studying relationship fMRI laterality to tumor-related variables (grade, genetics, location), patient-related (age, sex, handedness). Methods The study was retrospective cross-sectional. included patients with left-hemispheric tumors (study group) right-hemispheric (controls). calculated five indexes (LI): hemispheric, temporal lobe, frontal Broca’s area (BA), Wernicke’s (WA). defined LI ≥ 0.2 as left-lateralized (LL) < atypical lateralized (AL). Chi-square test ( p 0.05) employed identify tumor/patient in group. For those having significant results, confounding factors were a multinomial logistic regression model. Results 405 (235 M, mean age: 51 years old) 49 controls (36 old). Contralateral more common than controls. statistical analysis demonstrated association BA patient sex = 0.005); LI, location 0.001); hemispheric fibroblast factor receptor (FGFR) mutation 0.019); WA O6-methylguanine-DNA methyltransferase promoter (MGMT) methylation high-grade gliomas 0.016). Conclusions pathology, laterality, possibly due cortical Increased activation right hemisphere seen WA, FGFR mutation, MGMT methylation. Key Points • Patients harboring present contralateral translocation function. Influential for this phenomenon methylation, . plasticity, thereby affecting both dynamics In cross-sectional study, we brain by handedness)

Language: Английский

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Longitudinal Evaluation of Brain Plasticity in Low-Grade Gliomas: fMRI and Graph-Theory Provide Insights on Language Reorganization

Cancers, Journal Year: 2023, Volume and Issue: 15(3), P. 836 - 836

Published: Jan. 29, 2023

Language reorganization may represent an adaptive phenomenon to compensate tumor invasion of the dominant hemisphere. However, functional changes over time underlying language plasticity remain unknown. We evaluated function in patients with low-grade glioma (LGG), using task-based MRI (tb-fMRI), graph-theory and standardized assessment. hypothesized that networks obtained from tb-fMRI would show connectivity time, increased right-hemispheric participation. recruited five right-handed (4M, mean age 47.6Y) left-hemispheric LGG. Tb-fMRI assessment were conducted pre-operatively (pre-op), post-operatively: post-op1 (4-8 months), post-op2 (10-14 months) post-op3 (16-23 months). computed individual applying optimal percolation thresholding. dominance hemispheric quantified by laterality indices (LI) on fMRI maps matrices. A fixed linear mixed model was used assess intra-patient correlation trend LI values their performance. Individual showed inter-hemispheric right-sided involving areas homologues. Two patterns emerged: Three/five demonstrated a left-to-codominant shift pre-op (type 1). Two/five started as atypical at pre-op, remained unchanged 2). significant left-to-right all across timepoints. There no performance time. Type 1 be related treatment, while type 2 tumor-induced, since it already present pre-op. Increased right-side initial step develop plasticity.

Language: Английский

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