High-amplitude cofluctuations in cortical activity drive functional connectivity

Proceedings of the National Academy of Sciences, Год журнала: 2020, Номер 117(45), С. 28393 - 28401

Опубликована: Окт. 22, 2020

Significance Despite widespread applications, the origins of functional connectivity remain elusive. Here we analyze human neuroimaging data. We decompose resting-state across time to assess contributions moment-to-moment activity cofluctuations overall pattern. show that is driven by a small number high-amplitude frames. these frames are underpinned specific mode brain activity; topography this gets modulated during in-scanner tasks; and encode personalized, subject-specific information. In summary, our parameter-free method provides an exact mathematical link between frame-wise cofluctuations, creating opportunities for studying both static time-varying networks.

Язык: Английский

---

Controversies and progress on standardization of large-scale brain network nomenclature

Network Neuroscience, Год журнала: 2023, Номер 7(3), С. 864 - 905

Опубликована: Янв. 1, 2023

Progress in scientific disciplines is accompanied by standardization of terminology. Network neuroscience, at the level macroscale organization brain, beginning to confront challenges associated with developing a taxonomy its fundamental explanatory constructs. The Workgroup for HArmonized Taxonomy NETworks (WHATNET) was formed 2020 as an Organization Human Brain Mapping (OHBM)-endorsed best practices committee provide recommendations on points consensus, identify open questions, and highlight areas ongoing debate service moving field toward standardized reporting network neuroscience results. conducted survey catalog current large-scale brain nomenclature. A few well-known names (e.g., default mode network) dominated responses survey, number illuminating disagreement emerged. We summarize results initial considerations from workgroup. This perspective piece includes selective review this enterprise, including (1) scale, resolution, hierarchies; (2) interindividual variability networks; (3) dynamics nonstationarity (4) consideration affiliations subcortical structures; (5) multimodal information. close minimal guidelines cognitive communities adopt.

Язык: Английский

---

Edges in brain networks: Contributions to models of structure and function

Network Neuroscience, Год журнала: 2021, Номер unknown, С. 1 - 28

Опубликована: Авг. 13, 2021

Abstract Network models describe the brain as sets of nodes and edges that represent its distributed organization. So far, most discoveries in network neuroscience have prioritized insights highlight distinct groupings specialized functional contributions nodes. Importantly, these are determined expressed by web their interrelationships, formed edges. Here, we underscore important made for understanding Different types different relationships, including connectivity similarity among Adopting a specific definition can fundamentally alter how analyze interpret network. Furthermore, associate into collectives higher order arrangements, time series, form edge communities provide topology complementary to traditional node-centric perspective. Focusing on edges, or dynamic information they provide, discloses previously underappreciated aspects structural

Язык: Английский

---

Individualized event structure drives individual differences in whole-brain functional connectivity

NeuroImage, Год журнала: 2022, Номер 252, С. 118993 - 118993

Опубликована: Фев. 19, 2022

Resting-state functional connectivity is typically modeled as the correlation structure of whole-brain regional activity. It studied widely, both to gain insight into brain's intrinsic organization but also develop markers sensitive changes in an individual's cognitive, clinical, and developmental state. Despite this, origins drivers connectivity, especially at level densely sampled individuals, remain elusive. Here, we leverage novel methodology decompose its precise framewise contributions. Using two dense sampling datasets, investigate individualized focusing specifically on role brain network "events" - short-lived peaked patterns high-amplitude cofluctuations. a statistical test identify events empirical recordings. We show that cofluctuation expressed during are repeated across multiple scans same individual represent idiosyncratic variants template group level. Lastly, propose simple model based event cofluctuations, demonstrating group-averaged cofluctuations suboptimal for explaining participant-specific connectivity. Our work complements recent studies implicating brief instants primary static, extends those studies, individualized, positing dynamic basis

Язык: Английский

---

High-amplitude network co-fluctuations linked to variation in hormone concentrations over the menstrual cycle

Network Neuroscience, Год журнала: 2023, Номер 7(3), С. 1181 - 1205

Опубликована: Янв. 1, 2023

Abstract Many studies have shown that the human endocrine system modulates brain function, reporting associations between fluctuations in hormone concentrations and connectivity. However, how hormonal impact fast changes network organization over short timescales remains unknown. Here, we leverage a recently proposed framework for modeling co-fluctuations activity of pairs regions at framewise timescale. In previous showed time points corresponding to high-amplitude disproportionately contributed time-averaged functional connectivity pattern these co-fluctuation patterns could be clustered into low-dimensional set recurring “states.” assessed relationship states quotidian variation concentrations. Specifically, were interested whether frequency with which occurred was related concentration. We addressed this question using dense-sampling dataset (N = 1 brain). dataset, single individual sampled course two states: natural menstrual cycle while subject underwent selective progesterone suppression via oral contraceptives. During each cycle, 30 daily resting-state fMRI scans blood draws. Our analysis imaging data revealed repeating states. found state scan sessions significantly correlated follicle-stimulating luteinizing also constructed representative networks session only “event frames”—those when an event determined occurred. weights specific subsets connections robustly concentration not hormones, but estradiol.

Язык: Английский

---

Living on the edge: network neuroscience beyond nodes

Trends in Cognitive Sciences, Год журнала: 2023, Номер 27(11), С. 1068 - 1084

Опубликована: Сен. 15, 2023

Network neuroscience has emphasized the connectional properties of neural elements - cells, populations, and regions. This come at expense anatomical functional connections that link these to one another. A new perspective namely emphasizes 'edges' may prove fruitful in addressing outstanding questions network neuroscience. We highlight recently proposed 'edge-centric' method review its current applications, merits, limitations. also seek establish conceptual mathematical links between this previously approaches science neuroimaging literature. conclude by presenting several avenues for future work extend refine existing edge-centric analysis.

Язык: Английский

---

Lack of evidence for predictive utility from resting state fMRI data for individual exposure-based cognitive behavioral therapy outcomes: A machine learning study in two large multi-site samples in anxiety disorders

NeuroImage, Год журнала: 2024, Номер 295, С. 120639 - 120639

Опубликована: Май 25, 2024

Data-based predictions of individual Cognitive Behavioral Therapy (CBT) treatment response are a fundamental step towards precision medicine. Past studies demonstrated only moderate prediction accuracy (i.e. ability to discriminate between responders and non-responders given treatment) when using clinical routine data such as demographic questionnaire data, while neuroimaging achieved superior accuracy. However, these may be considerably biased due very limited sample sizes bias-prone methodology. Adequately powered cross-validated samples prerequisite evaluate predictive performance identify the most promising predictors. We therefore analyzed resting state functional magnet resonance imaging (rs-fMRI) from two large trials test whether continues provide good in much larger samples. Data came distinct German multicenter on exposure-based CBT for anxiety disorders, Protect-AD SpiderVR studies. separately independently preprocessed baseline rs-fMRI n = 220 patients (Protect-AD) 190 (SpiderVR) extracted variety features, including ROI-to-ROI edge-functional connectivity, sliding-windows, graph measures. Including features sophisticated machine learning pipelines, we found that outcomes never significantly differed chance level, even conducting range exploratory post-hoc analyses. Moreover, provided beyond sociodemographic data. The analyses were independent each other terms selecting methods process input well used parameters corroborating external validity results. These similar findings studies, separately, urge caution regarding interpretation results based small emphasizes some accuracies previous result overestimation homogeneous weak cross-validation schemes. promise resting-state play an important role with disorders remains yet delivered.

Язык: Английский

---

Edge-centric analysis of stroke patients: An alternative approach for biomarkers of lesion recovery

NeuroImage Clinical, Год журнала: 2022, Номер 35, С. 103055 - 103055

Опубликована: Янв. 1, 2022

Most neuroimaging studies of post-stroke recovery rely on analyses derived from standard node-centric functional connectivity to map the distributed effects in stroke patients. Here, given importance nonlocal and diffuse damage, we use an edge-centric approach order provide alternative description this disorder. These techniques allow for rendering metrics such as normalized entropy, which describes diversity edge communities at each node. Moreover, enables identification high amplitude co-fluctuations fMRI time series. We found that entropy is associated with lesion severity continually increases across patients' recovery. Furthermore, not only relate but are also level The current study first application a clinical population longitudinal dataset demonstrates how different perspective data analysis can further characterize topographic modulations brain dynamics.

Язык: Английский

---

Cortico-subcortical interactions in overlapping communities of edge functional connectivity

NeuroImage, Год журнала: 2022, Номер 250, С. 118971 - 118971

Опубликована: Фев. 4, 2022

Both cortical and subcortical regions can be functionally organized into networks. Regions of the basal ganglia are extensively interconnected with cortex via reciprocal connections that relay modulate function. Here we employ an edge-centric approach, which computes co-fluctuations among region pairs in a network to investigate role interaction systems. By clustering edges communities, show systems couple multiple edge hippocampus amygdala having distinct pattern from striatum thalamus. We community structure networks is highly similar one obtained nodes when subcortex present network. Additionally, profile both estimates solely cortico-subcortical interactions. Finally, used motif analysis focusing on triads where coupled two found couples were overrepresented. In summary, our results coupling may play organization primary sensorimotor/attention heteromodal puts forth as promising method for investigation communication patterns

Язык: Английский

---

A survey of brain functional network extraction methods using fMRI data

Trends in Neurosciences, Год журнала: 2024, Номер 47(8), С. 608 - 621

Опубликована: Июнь 20, 2024

Язык: Английский

---