Human brain dynamics are shaped by rare long-range connections over and above cortical geometry

Proceedings of the National Academy of Sciences, Journal Year: 2025, Volume and Issue: 122(1)

Published: Jan. 3, 2025

A fundamental topological principle is that the container always shapes content. In neuroscience, this translates into how brain anatomy dynamics. From neuroanatomy, topology of mammalian can be approximated by local connectivity, accurately described an exponential distance rule (EDR). The compact, folded geometry cortex shaped and geometric harmonic modes reconstruct much functional However, ignores role rare long-range (LR) cortical connections, crucial for improving information processing in brain, but not captured folding geometry. Here, we show superiority combining LR connectivity with EDR (EDR+LR) capturing dynamics (specifically task-evoked activity) compared to representations. Importantly, orchestration carried out a more efficient manifold made up low number EDR+LR modes. Our results importance complexity activity through low-dimensional

Language: Английский

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Neural Activity in Quarks Language: Lattice Field Theory for a Network of Real Neurons

Entropy, Journal Year: 2024, Volume and Issue: 26(6), P. 495 - 495

Published: June 6, 2024

Brain–computer interfaces have seen extraordinary surges in developments recent years, and a significant discrepancy now exists between the abundance of available data limited headway made achieving unified theoretical framework. This becomes particularly pronounced when examining collective neural activity at micro meso scale, where coherent formalization that adequately describes interactions is still lacking. Here, we introduce mathematical framework to analyze systems natural neurons interpret related empirical observations terms lattice field theory, an established paradigm from particle physics statistical mechanics. Our methods are tailored chronic interfaces, especially spike rasters measurements single neuron activity, generalize maximum entropy model for networks so time evolution system also taken into account. obtained by bridging neuroscience, paving way physics-inspired models neocortex.

Language: Английский

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Modular subgraphs in large-scale connectomes underpin spontaneous co-fluctuation events in mouse and human brains

Communications Biology, Journal Year: 2024, Volume and Issue: 7(1)

Published: Jan. 24, 2024

Abstract Previous studies have adopted an edge-centric framework to study fine-scale network dynamics in human fMRI. To date, however, no applied this data collected from model organisms. Here, we analyze structural and functional imaging lightly anesthetized mice through lens. We find evidence of “bursty” events - brief periods high-amplitude connectivity. Further, show that on a per-frame basis best explain static FC can be divided into series hierarchically-related clusters. The co-fluctuation patterns associated with each cluster centroid link distinct anatomical areas largely adhere the boundaries algorithmically detected brain systems. then investigate connectivity undergirding patterns. induce modular bipartitions inter-areal axonal projections. Finally, replicate these same findings dataset. In summary, report recapitulates organism many phenomena observed previously analyses data. However, unlike subjects, murine nervous system is amenable invasive experimental perturbations. Thus, sets stage for future investigation causal origins co-fluctuations. Moreover, cross-species consistency reported enhances likelihood translation.

Language: Английский

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Beyond cortical geometry: brain dynamics shaped by long-range connections

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

Published: April 9, 2024

A fundamental topological principle is that the container always shapes content. In neuroscience, this translates into how brain anatomy dynamics. From neuroanatomy, topology of mammalian can be approximated by local connectivity, accurately described an exponential distance rule (EDR). The compact, folded geometry cortex shaped connectivity and geometric harmonic modes reconstruct much functional However, ignores role rare long-range cortical connections, crucial for improving information processing in brain, but not captured folding geometry. Here we show superiority combining with EDR (EDR+LR) capturing dynamics (specifically task-evoked activity) compared to representations. Importantly, orchestration carried out a more efficient manifold made up low number EDR+LR modes. Our results importance complexity activity through low-dimensional

Language: Английский

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Eigenmodes of the brain: revisiting connectomics and geometry

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

Published: April 20, 2024

Eigenmodes can be derived from various structural brain properties, including cortical surface geometry 1 and interareal axonal connections comprising an organism’s connectome 2 . Pang colleagues map geometric eigenmodes to spatial patterns of human activity, assessing whether connectivity or provide greater explanatory power function 3 The authors find that are superior predictors activity compared eigenmodes. They conclude this supports the predictions neural field theory (NFT) 4 , in “brain is best represented terms directly shape cortex, thus emphasizing a fundamental role constraining dynamics”. experimental comparisons favoring over eigenmodes, conjunction with specific statements regarding relative efficacy representing have been widely interpreted mean imposes stronger constraints on dynamics than 5–9 Here, we reconsider comparative evidence focusing impact mapping methodology. Utilizing established methods mitigate construction limitations, new connectomes for same dataset, finding these reach comparable accuracy explaining We presented support proposition “eigenmodes represent more anatomical constraint connectome” may require reconsideration light our findings. present compelling important function, but their findings should not has connectome.

Language: Английский

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Reply to: Commentary on Pang et al. (2023) Nature

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

Published: Oct. 9, 2023

Abstract In Pang et al. (2023) 1 , we identified a close link between the geometry and function of human brain by showing that: (1) eigenmodes derived from cortical parsimoniously reconstruct activity patterns recorded with functional magnetic resonance imaging (fMRI); (2) task-evoked results excitations brain-wide modes long wavelengths; (3) wave dynamics, constrained distance-dependent connectivity, can account for diverse aspects spontaneous evoked activity; (4) are strongly coupled in subcortex. Faskowitz 2 raise concerns about framing our paper specificity eigenmode reconstructions result (1). Here, address these show how is established using appropriate benchmarks.

Language: Английский

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Commentary on Pang et al. (2023) Nature

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

Published: Oct. 9, 2023

Abstract Pang et al. (2023) observe that the geometric eigenmodes, derived from shape of cortical surface, are better at reconstructing patterns both spontaneous and stimulus-evoked activity, when contrasted with three alternative connectome-based models including structural connectome eigenmodes. Based on this observation they propose eigenmodes offer a good model for explaining brain function, noting “ wave dynamics more accurate parsimonious mechanistic account macroscale, captured by fMRI ”. They then question prevailing view activity is localized to focal, spatially isolated clusters ” it driven intricate anatomical connections While properties fit well intriguing, we argue accepting as function risks logical fallacy “affirming consequent”. A representation effectively describes underlying geometry inherently adept fitting within space; does not necessarily shed light mechanisms brain’s functional attributes. To end, provide two lines empirical results: (a) Basic parcel-based representations, which capture structures, can reconstruct well. (b) Geometric demonstrate high flexibility range manipulated patterns, evokes danger overfitting. those results, theoretical considerations, previous data consideration needed regarding “parsimony, robustness generality basis set function”. recognize potential role in influencing its dynamics, assertions efficacy should be weighed against performance simpler models, an inherent risk overfitting evidence. 1 put forth harmonic modes previously underrecognized explain brain-wide dynamics. Their reconstruction framework relies multiple linear regression using calculating Pearson’s correlation between original fitted data, parcellated atlas 180 parcels each hemisphere 2 . In addition overarching challenge any actual reflection real world 3 , here results arguments highlight need further macroscale activity.

Language: Английский

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Ketamine-Induced Unresponsiveness Shows a Harmonic Shift from Global to Localised Functional Organisation.

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

Published: June 25, 2024

Abstract Ketamine is classified as a dissociative anaesthetic that, in sub-anaesthetic doses, can produce an altered state of consciousness characterised by symptoms, visual and auditory hallucinations, perceptual distortions. Given the anaesthetic-like psychedelic-like nature this compound, it expected to have different effects on brain dynamics doses than low, doses. We investigated question using connectome harmonic decomposition (CHD), recently developed method decompose activity terms network organisation underlying human structural connectome. Previous research has revealed signatures responsiveness, with increased influence global structure disorders propofol-induced sedation, localised patterns under classic psychedelics ketamine, compared normal wakefulness. When we applied CHD analytical framework resting-state fMRI data volunteers during ketamine-induced unresponsiveness, found prevalence harmonics, reminiscent states consciousness. This from traditional GABAergic where instead rather harmonics seems increase higher In addition, that ketamine’s signature shows alignment those seen LSD- or psilocybin-induced psychedelic unconscious individuals, whether due propofol sedation injury. Together, results indicate which does not necessarily suppress conscious experience, opposite way hypnotics. conclude offers possibility track alterations awareness (e.g., dreams, sensations) behavioural responsiveness – discovery made possible unique property decoupling these two facets.

Language: Английский

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Decomposing cortical activity through neuronal tracing connectome-eigenmodes in marmosets

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

Published: March 13, 2024

Abstract Deciphering the complex relationship between neuroanatomical connections and functional activity in primate brains remains a daunting task, especially regarding influence of monosynaptic connectivity on cortical activity. Here, we investigate anatomical-functional decompose neuronal-tracing connectome marmoset into series eigenmodes using graph signal processing. These cellular effectively constrain derived from resting-state MRI, uncover patterned cellular-functional decoupling. This pattern reveals spatial gradient coupled dorsal-posterior to decoupled ventral-anterior cortices, recapitulates micro-structural profiles macro-scale hierarchical organization. Notably, these marmoset-derived may facilitate inference spontaneous homologous areas humans, highlighting potential generalizing connectomic constraints across species. Collectively, our findings illuminate how improve understanding brain’s relationship.

Language: Английский

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Structure-function coupling and decoupling during movie-watching and resting-state: Novel insights bridging EEG and structural imaging

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

Published: April 9, 2024

Abstract The intricate structural and functional architecture of the brain enables a wide range cognitive processes ranging from perception action to higher-order abstract thinking. Despite important progress, relationship between brain’s properties is not yet fully established. In particular, way anatomy shapes its electrophysiological dynamics remains elusive. electroencephalography (EEG) activity recorded during naturalistic tasks thought exhibit patterns coupling with underlying structure that vary as function behavior. Yet these have been sufficiently quantified. We address this gap by jointly examining individual Diffusion-Weighted Imaging (DWI) scans continuous EEG video-watching resting state, using Graph Signal Processing (GSP) framework. By decomposing graph into Eigenmodes expressing an extension anatomy, GSP provides quantify structure-function coupling. elucidate how such movie-watching association modulated tasks. in region-, time-, frequency-resolved manner. First all, our findings indicate sensorimotor cortex strongly coupled structure, while systems less constrained i.e., shows more flexibility. addition, we found watching videos was associated stronger cortex, compared resting-state data. Second, time-resolved analysis revealed unimodal undergo minimal temporal fluctuation association, transmodal system displays highest fluctuations, exception PCC seeing low fluctuations. Lastly, consistent topography across different rhythms, suggesting similar anatomical frequency bands. Together, unprecedented characterization link behavior underscores role shaping ongoing processes. Taken together, combining spectral resolution methodological advantages GSP, work sheds new light onto anatomo-functional organization brain.

Language: Английский

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