A multi-modal, asymmetric, weighted, and signed description of anatomical connectivity

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: July 12, 2024

Abstract The macroscale connectome is the network of physical, white-matter tracts between brain areas. connections are generally weighted and their values interpreted as measures communication efficacy. In most applications, weights either assigned based on imaging features–e.g. diffusion parameters–or inferred using statistical models. reality, ground-truth unknown, motivating exploration alternative edge weighting schemes. Here, we explore a multi-modal, regression-based model that endows reconstructed fiber with directed signed weights. We find fits observed data well, outperforming suite null estimated subject-specific highly reliable, even when fit relatively few training samples, networks maintain number desirable features. summary, offer simple framework for data, demonstrating both its ease implementation while benchmarking utility typical analyses, including graph theoretic modeling brain-behavior associations.

Language: Английский

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Relation of connectome topology to brain volume across 103 mammalian species

PLoS Biology, Journal Year: 2024, Volume and Issue: 22(2), P. e3002489 - e3002489

Published: Feb. 5, 2024

The brain connectome is an embedded network of anatomically interconnected regions, and the study its topological organization in mammals has become paramount importance due to role scaffolding function behavior. Unlike many other observable networks, connections incur material energetic cost, their length density are volumetrically constrained by skull. Thus, open question how differences volume impact topology. We address this issue using MaMI database, a diverse set mammalian connectomes reconstructed from 201 animals, covering 103 species 12 taxonomy orders, whose size varies over more than 4 orders magnitude. Our analyses focus on relationships between modular organization. After having identified modules through multiresolution approach, we observed connectivity features relate structure these relations vary across volume. found that as increases, spatially compact dense, comprising costly connections. Furthermore, investigated spatial embedding shapes communication, finding nodes’ distance progressively impacts communication efficiency. modes variation policies, smaller bigger brains show higher efficiency routing- diffusion-based signaling, respectively. Finally, bridging modularity larger brains, imposes stronger constraints signaling. Altogether, our results systematically related topology tighter restrictions brains.

Language: Английский

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Benchmarking methods for mapping functional connectivity in the brain

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: May 8, 2024

The networked architecture of the brain promotes synchrony among neuronal populations and emergence coherent dynamics. These communication patterns can be comprehensively mapped using noninvasive functional imaging, resulting in connectivity (FC) networks. Despite its popularity, FC is a statistical construct operational definition arbitrary. While most studies use zero-lag Pearson's correlations by default, there exist hundreds pairwise interaction statistics broader scientific literature that used to estimate FC. How organization matrix varies with choice statistic fundamental methodological question affects all this rapidly growing field. Here we benchmark topological geometric organization, neurobiological associations, cognitive-behavioral relevance matrices computed large library 239 statistics. We investigate how canonical features networks vary statistic, including (1) hub mapping, (2) weight-distance trade-offs, (3) structure-function coupling, (4) correspondence other neurophysiological networks, (5) individual fingerprinting, (6) brain-behavior prediction. find substantial quantitative qualitative variation across methods. Throughout, observe measures such as covariance (full correlation), precision (partial correlation) distance display multiple desirable properties, close structural connectivity, capacity differentiate individuals predict differences behavior. Using information flow decomposition, methods may arise from differential sensitivity underlying mechanisms inter-regional communication, some more sensitive redundant synergistic flow. In summary, our report highlights importance tailoring specific mechanism research question, providing blueprint for future optimize their method.

Language: Английский

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Fundamental interactions in self-organised critical dynamics on higher order networks

The European Physical Journal B, Journal Year: 2024, Volume and Issue: 97(6)

Published: June 1, 2024

Abstract In functionally complex systems, higher order connectivity is often revealed in the underlying geometry of networked units. Furthermore, such systems show signatures self-organised criticality, a specific type non-equilibrium collective behaviour associated with an attractor internal dynamics long-range correlations and scale invariance, which ensures robust functioning as brain. Here, we highlight intertwining features critical plausible mechanism for emergence new properties on larger scale, representing central paradigm physical notion complexity. Considering time-scale structural evolution known separation i.e., external driving, distinguish three classes geometries that can shape them differently. We provide overview current trends study phenomena, synchronisation phase oscillators discrete spin couplings embedded faces simplicial complexes. For representative example induced by structures, present more detailed analysis field-driven reversal hysteresis loops complexes composed triangles. These numerical results suggest two fundamental interactions edge-embedded triangle-embedded must be taken into account theoretical models to describe influence dynamics. Graphical abstract

Language: Английский

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Structure–function coupling reveals the brain hierarchical structure dysfunction in Alzheimer's disease: A multicenter study

Alzheimer s & Dementia, Journal Year: 2024, Volume and Issue: 20(9), P. 6305 - 6315

Published: July 28, 2024

Abstract BACKGROUND Alzheimer's disease (AD) is a neurodegenerative condition characterized by cognitive decline. To date, the specific dysfunction in brain's hierarchical structure AD remains unclear. METHODS We introduced structural decoupling index (SDI), based on multi‐site data set comprising functional and diffusion‐weighted magnetic resonance imaging from 793 subjects, to assess their brain hierarchy. RESULTS Compared normal controls (NCs), individuals with exhibited increased SDI within posterior superior temporal sulcus, insular gyrus, precuneus, hippocampus, amygdala, postcentral cingulate gyrus; meanwhile, patients demonstrated decreased frontal lobe. The those regions also showed significant correlation ability. Moreover, was robust neuroimaging biomarker capable of accurately distinguishing diagnostic status (area under curve [AUC] = 0.86). DISCUSSION Our findings revealed AD. Furthermore, could serve as promising for Highlights This study utilized multi‐center, multi‐modal East Asian populations. found an spatial gradient (SDI) sensory–motor higher‐order regions. Changes are associated energy metabolism mitochondria. can identify further uncover mechanisms

Language: Английский

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Neural network architecture of a mammalian brain

Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(39)

Published: Sept. 17, 2024

Connectomics research is making rapid advances, although models revealing general principles of connectional architecture are far from complete. Our analysis 10 6 published connection reports indicates that the adult rat brain interregional connectome has about 76,940 a possible 623,310 axonal connections between its 790 gray matter regions mapped in reference atlas, equating to network density 12.3%. We examined sexually dimorphic using multiresolution consensus clustering generated nested hierarchy interconnected modules/subsystems with three first-order modules and 157 terminal females. Top–down suggests mirror-image primary module pair central nervous system’s rostral sector (forebrain–midbrain) associated behavior control, single intermediate (rhombicbrain) execution; implications these results considered relation development evolution. Bottom–up reveals known unfamiliar suggesting strong experimentally testable hypotheses. Global analyses indicate all hubs pair, rich club extends through modules, exhibits small-world attributes. Simulated lesions individually enabled ranking their impact on global organization, visual path retina was used as specific example, including effects cyclic weight changes endogenous circadian rhythm generator, suprachiasmatic nucleus. This study elucidates neuronal for mammalian strategy modeling dynamic structural connectivity.

Language: Английский

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Local structural-functional coupling with counterfactual explanations for epilepsy prediction

NeuroImage, Journal Year: 2025, Volume and Issue: 306, P. 120978 - 120978

Published: Jan. 2, 2025

The structural-functional brain connections coupling (SC-FC coupling) describes the relationship between white matter structural (SC) and corresponding functional activation or (FC). It has been widely used to identify disorders. However, existing research on SC-FC focuses global regional scales, few studies have investigated impact of disorders this from perspective multi-brain region cooperation (i.e., local scale). Here, we propose pattern for prediction. Compared with previous methods, proposed patterns quantify SC FC in terms subgraphs rather than whole single regions. Specifically, first construct using diffusion tensor imaging (DTI) resting-state magnetic resonance (rs-fMRI) data, subsequently organizing them into a multimodal network. Then, extract these networks select based their frequencies generate patterns. Finally, employ while refining abnormal counterfactual explanations. Results real epilepsy dataset suggest that method not only outperforms methods accuracy but also provides insights changes Code available at https://github.com/UAIBC-Brain/Local-SC-FC-coupling-pattern.

Language: Английский

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Learning to hear again with alternating cochlear frequency allocations

Scientific Reports, Journal Year: 2025, Volume and Issue: 15(1)

Published: Jan. 2, 2025

Traditionally, the place-pitch 'tonotopically' organized auditory neural pathway was considered to be hard-wired. Cochlear implants restore hearing by arbitrarily mapping frequency-amplitude information. This study shows that recipients, after a long period of sound deprivation, preserve level plasticity, enabling them swiftly and concurrently learn speech understanding with two alternating, distinct frequency maps. During rehabilitation, subjects switched maps randomly on daily basis, serving as their own control. After stating preference, average, maintained performance non-preferred, legacy map over time. In addition, continued improve preference. Being able train process information from did not seem competition resources, such would case in typical zero-sum game. new flexibility learning long-term adaptation system. Practically, required novel design halves sample size while mitigating order effects associated benefitting sensory-oriented trials.

Language: Английский

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Hierarchical Neurocognitive Model of Externalizing and Internalizing Comorbidity

Published: Jan. 10, 2025

Mounting evidence suggests hierarchical psychopathology factors underlying psychiatric comorbidity. However, the exact neurobiological characterizations of these multilevel remain elusive. In this study, leveraging brain-behavior predictive framework with a 10-year longitudinal imaging-genetic cohort (IMAGEN, ages 14, 19 and 23, N = 1,750), we constructed two neural externalizing internalizing symptoms, which were reproducible across six clinical population-based datasets (ABCD, STRATIFY/ ESTRA, ABIDE II, ADHD-200 XiNan, from age 10 to 36, 3,765). These exhibit distinct configurations: hyperconnectivity in impulsivity-related circuits for symptoms hypoconnectivity goal-directed symptoms. Both also differ their cognitive-behavior relevance, genetic substrates developmental profiles. Together previous studies, findings propose neurocognitive spectral model comorbid mental illnesses preadolescence adulthood: general neuropsychopathological (NP) factor (manifested as inefficient executive control) stratified (deficient inhibition (impaired function) respectively. holistic insights are crucial development therapeutic interventions disorders.

Language: Английский

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Bayesian approaches for revealing complex neural network dynamics in Parkinson’s disease

Journal of Computational Science, Journal Year: 2025, Volume and Issue: unknown, P. 102525 - 102525

Published: Jan. 1, 2025

Language: Английский

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