Advanced lesion symptom mapping analyses and implementation as BCBtoolkit

GigaScience, Journal Year: 2018, Volume and Issue: 7(3)

Published: Feb. 8, 2018

Patients with brain lesions provide a unique opportunity to understand the functioning of human mind. However, even when focal, have local and remote effects that impact functionally structurally connected circuits. Similarly, function emerges from interaction between areas rather than their sole activity. For instance, category fluency requires associations executive, semantic, language production functions.Here, we provide, for first time, set complementary solutions measuring given lesion on neuronal Our methods, which were applied 37 patients focal frontal lesions, revealed large directly indirectly disconnected regions had significantly impacted performance. The corresponded are classically considered as engaged in verbal categorization tasks. These also organized into larger functional networks, including left ventral fronto-parietal network, whose cortical thickness correlated performance fluency.The combination structural connectivity together estimates reveal identification affected strengthen our understanding relationship cognitive behavioral measures. methods presented available freely accessible BCBtoolkit supplementary software [1].

Language: Английский

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Improved accuracy of lesion to symptom mapping with multivariate sparse canonical correlations

Neuropsychologia, Journal Year: 2017, Volume and Issue: 115, P. 154 - 166

Published: Sept. 5, 2017

Language: Английский

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Strategic infarct location for post-stroke cognitive impairment: A multivariate lesion-symptom mapping study

Journal of Cerebral Blood Flow & Metabolism, Journal Year: 2017, Volume and Issue: 38(8), P. 1299 - 1311

Published: Sept. 12, 2017

Lesion location is an important determinant for post-stroke cognitive impairment. Although several ‘strategic’ brain regions have previously been identified, a comprehensive map of strategic impairment lacking due to limitations in sample size and methodology. We aimed determine by applying multivariate lesion-symptom mapping large cohort 410 acute ischemic stroke patients. Montreal Cognitive Assessment at three six months after was used assess global functioning domains (memory, language, attention, executive visuospatial function). The relation between infarct cognition assessed analyses the voxel-level level interest using support vector regression. These two assumption-free consistently identified left angular gyrus, basal ganglia structures white matter around as stroke. A network involving overlapping domain-specific cortical subcortical each domains. Future studies should aim develop even more location-based models through multicenter including thousands

Language: Английский

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Structural Disconnections Explain Brain Network Dysfunction after Stroke

Cell Reports, Journal Year: 2019, Volume and Issue: 28(10), P. 2527 - 2540.e9

Published: Sept. 1, 2019

Stroke causes focal brain lesions that disrupt functional connectivity (FC), a measure of activity synchronization, throughout distributed networks. It is often assumed FC disruptions reflect damage to specific cortical regions. However, an alternative explanation they the structural disconnection (SDC) white matter pathways. Here, we compare these explanations using data from 114 stroke patients. Across multiple analyses, find SDC measures outperform measures, including putative critical regions, for explaining associated with stroke. We also identify core mode structure-function covariation links severity interhemispheric SDCs widespread across patients and correlates deficits in behavioral domains. conclude lesion's impact on connectome what determines its may play particularly important role mediating after

Language: Английский

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Lesion Quantification Toolkit: A MATLAB software tool for estimating grey matter damage and white matter disconnections in patients with focal brain lesions

NeuroImage Clinical, Journal Year: 2021, Volume and Issue: 30, P. 102639 - 102639

Published: Jan. 1, 2021

Lesion studies are an important tool for cognitive neuroscientists and neurologists. However, while brain lesion have traditionally aimed to localize neurological symptoms specific anatomical loci, a growing body of evidence indicates that diseases such as stroke best conceptualized network disorders. While researchers in the fields neuroscience neurology therefore increasingly interested quantifying effects focal lesions on white matter connections form brain's structural connectome, few dedicated tools exist facilitate this endeavor. Here, we present Quantification Toolkit, publicly available MATLAB software package impacts lesions. The Toolkit uses atlas-based approaches estimate parcel-level grey loads multiple measures disconnection severity include tract-level measures, voxel-wise maps, parcel-wise matrices. toolkit also estimates lesion-induced increases lengths shortest paths between parcel pairs, which provide information about changes higher-order topology. We describe detail each different produced by toolkit, discuss their applications considerations relevant use, perform example analyses using real behavioral data collected from sub-acute patients. show performed produce results highly consistent with been reported prior literature, demonstrate consistency obtained conducted toolkit. anticipate will empower address research questions would be difficult or impossible traditional alone, ultimately, lead advances our understanding how disconnections contribute cognitive, behavioral, physiological consequences

Language: Английский

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Post-stroke outcomes predicted from multivariate lesion-behaviour and lesion network mapping

Brain, Journal Year: 2022, Volume and Issue: 145(4), P. 1338 - 1353

Published: Jan. 10, 2022

Abstract Clinicians and scientists alike have long sought to predict the course severity of chronic post-stroke cognitive motor outcomes, as ability do so would inform treatment rehabilitation strategies. However, it remains difficult make accurate predictions about outcomes due, in large part, high inter-individual variability recovery a reliance on clinical heuristics rather than empirical methods. The neuroanatomical location stroke is key variable associated with long-term because lesion can be derived from routinely collected neuroimaging data there an opportunity use this information empirically based deficits. For example, compared statistically weighted multivariate lesion-behaviour maps regions that, when damaged, are specific deficits aggregated outcome cohorts. Here, our goal was evaluate whether we leverage two cohorts individuals focal brain lesions 12-month independent sample patients. Further, evaluated could augment these by estimating structural functional networks disrupted association each map through network mapping, which normative connectivity neurologically healthy elucidate lesion-associated networks. We using anatomical strongest impairment for results. These peak regional findings became ‘seeds’ generate networks, approach that offers potentially greater precision previously used single-lesion approaches. Next, sample, quantified overlap mapping how much variance explain behavioural latent growth curve statistical model. found lesion-deficit modality able significant amount outcomes. Both were beyond mapping. Functional performed best prediction language deficits, Altogether, results support notion combined improve at 12-months.

Language: Английский

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Damage to Broca’s area does not contribute to long-term speech production outcome after stroke

Brain, Journal Year: 2020, Volume and Issue: 144(3), P. 817 - 832

Published: Dec. 28, 2020

Abstract Broca’s area in the posterior half of left inferior frontal gyrus has long been thought to be critical for speech production. The current view is that long-term production outcome patients with damage best explained by combination and neighbouring regions including underlying white matter, which was also damaged Paul two historic cases. Here, we dissociate effect from surrounding areas studying 134 stroke survivors relatively circumscribed lobe lesions spared lateral parietal superior temporal association cortices. Collectively, these had varying degrees one or more nine atlas-based grey matter regions: Brodmann 44 45 (together known as area), ventral premotor cortex, primary motor insula, putamen, anterior segment arcuate fasciculus, uncinate fasciculus aslant tract. Spoken picture description scores Comprehensive Aphasia Test were used measure. Multiple regression analyses allowed us tease apart contribution other variables influencing abilities such total lesion volume time post-stroke. We found that, our sample damage, impairments (lasting beyond 3 months post-stroke) solely predicted degree directly above vicinity part no (as confirmed Bayesian statistics). cannot a disconnection area, because worse after relative sparing than fasciculus. Our findings provide evidence three novel conclusions: (i) does not contribute strokes; (ii) persistent area; (iii) prior between can co-occurring

Language: Английский

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Functional Contributions of the Arcuate Fasciculus to Language Processing

Frontiers in Human Neuroscience, Journal Year: 2021, Volume and Issue: 15

Published: June 25, 2021

Current evidence strongly suggests that the arcuate fasciculus (AF) is critical for language, from spontaneous speech and word retrieval to repetition comprehension abilities. However, further pinpoint its unique differential role in anatomy needs be explored greater detail contribution language processing beyond of known cortical areas must established. We address this a comprehensive evaluation specific functional AF well-characterized cohort individuals with chronic aphasia (n = 33) following left hemisphere stroke. To evaluate macro- microstructural integrity AF, tractography based on constrained spherical deconvolution model was performed. The right hemispheres were then manually reconstructed using modified 3-segment (Catani et al., 2005), 2-segment (Glasser Rilling, 2008). normalized volume measure long posterior segments significantly correlated indices while controlling gender lesion volume. Specific contributions accounting - inferior frontal, parietal, temporal tested multiple regression analyses. Involvement tract demonstrated: segment contributed naming abilities; anterior fluency naming; comprehension. results highlight important fiber pathways impairments areas. At same time, no clear tracts could ascertained. In sum, our findings lend support broader processing, particular emphasis naming, point as being most crucial supporting residual

Language: Английский

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Cognitive impairment after focal brain lesions is better predicted by damage to structural than functional network hubs

Proceedings of the National Academy of Sciences, Journal Year: 2021, Volume and Issue: 118(19)

Published: May 3, 2021

Significance Hubs are highly connected brain regions that important for coordinating processing in networks and supporting cognition. There several different methods characterizing network hubs gray white matter, yet it is unclear which of these hub measures identify sites most critical Here, we use data from two large cohorts patients with focal damage to show lesions matter dense structural connections have the strongest association cognitive impairment, while functional centrality weaker associations. These findings highlight role densely cognition, helps explain interindividual differences outcomes following damage.

Language: Английский

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A narrative review of the anatomy and function of the white matter tracts in language production and comprehension

Frontiers in Human Neuroscience, Journal Year: 2023, Volume and Issue: 17

Published: March 27, 2023

Much is known about the role of cortical areas in language processing. The shift towards network approaches recent years has highlighted importance uncovering white matter connecting these areas. However, despite a large body research, many tracts' functions are not well-understood. We present comprehensive review empirical evidence on eight major tracts that hypothesized to be involved processing (inferior longitudinal fasciculus, inferior fronto-occipital uncinate extreme capsule, middle superior arcuate and frontal aslant tract). For each tract, we hypothesize its based function regions it connects. then evaluate hypotheses with data from three sources: studies neurotypical individuals, neuropsychological data, intraoperative stimulation studies. Finally, summarize conclusions supported by highlight needing further investigation.

Language: Английский

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