Aberrant Functional Organization within and between Resting-State Networks in AD

ABSTRACTResting-state networks are spatially distributed, functionally connected brain regions. Studying these networks gives us information about the large-scale functional organization of the brain and alternations in these networks are considered to play a role in a wide range of neurological conditions and aging. To describe resting-state networks in dogs, we measured 22 awake, unrestrained animals of either sex and carried out group-level spatial independent component analysis to explore whole-brain connectivity patterns. Using resting-state functional magnetic resonance imaging (rs-fMRI), in this exploratory study we found multiple resting-state networks in dogs, which resemble the pattern described in humans. We report the following dog resting-state networks: default mode network (DMN), visual network (VIS), sensorimotor network (SMN), combined auditory (AUD)-saliency (SAL) network and cerebellar network (CER). The DMN, similarly to Primates, but unlike previous studies in dogs, showed antero-posterior connectedness with involvement of hippocampal and lateral temporal regions. The results give us insight into the resting-state networks of awake animals from a taxon beyond rodents through a non-invasive method.

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Altered Functional Organization within and between Resting-State Networks in Chronic Subcortical Infarction

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.2013.238 ◽

2014 ◽

Vol 34 (4) ◽

pp. 597-605 ◽

Cited By ~ 51

Author(s):

Caihong Wang ◽

Wen Qin ◽

Jing Zhang ◽

Tian Tian ◽

Ying Li ◽

...

Keyword(s):

Resting State ◽

Functional Organization ◽

Resting State Networks ◽

Imaging Data ◽

Functional Magnetic Resonance ◽

Magnetic Resonance Imaging Data ◽

Stroke Patients ◽

Frontoparietal Network ◽

Normal Controls ◽

Subcortical Infarction

This study aimed to investigate the changes in functional connectivity (FC) within each resting-state network (RSN) and between RSNs in subcortical stroke patients who were well recovered in global motor function. Eleven meaningful RSNs were identified via functional magnetic resonance imaging data from 25 subcortical stroke patients and 22 normal controls using independent component analysis. Compared with normal controls, stroke patients exhibited increased intranetwork FC in the sensorimotor (SMN), visual (VN), auditory (AN), dorsal attention (DAN), and default mode (DMN) networks; they also exhibited decreased intranetwork FC in the frontoparietal network (FPN) and anterior DMN. Stroke patients displayed a shift from no FC in controls to negative internetwork FC between the VN and AN as well as between the VN and SMN. Stroke patients also exhibited weakened positive (anterior and posterior DMN; posterior DMN and right FPN) or negative (AN and right FPN; posterior DMN and dorsal SMN) internetwork FC when compared with normal controls. We suggest that subcortical stroke may induce connectivity changes in multiple functional networks, affecting not only the intranetwork FC within RSNs but also the internetwork FC between these RSNs.

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Reconstruction of resting-state networks from macaque electrocorticographic data

10.1101/221051 ◽

2017 ◽

Cited By ~ 1

Author(s):

R. Hindriks ◽

C. Micheli ◽

C.A. Bosman ◽

R. Oostenveld ◽

C. Lewis ◽

...

Keyword(s):

Network Structure ◽

Resting State ◽

Functional Organization ◽

Phase Locking ◽

Simulated Data ◽

Resting State Networks ◽

Cortical Rhythms ◽

Oscillatory Phase ◽

Phase Lags ◽

Band Limited

AbstractThe discovery of haemodynamic (BOLD-fMRI) resting-state networks (RSNs) has brought about a fundamental shift in our thinking about the role of intrinsic brain activity. The electrophysiological underpinnings of RSNs remain largely elusive and it has been shown only recently that electrophysiological cortical rhythms are organized into RSNs. Most electrophysiological studies into RSNs use magnetoencephalography (MEG) or electroencephalography (EEG), which limits the spatial scale on which RSNs can be investigated. Due to their close proximity to the cortical surface, electroencephalographic (ECoG) recordings can potentially provide a more detailed picture of the functional organization of resting-state cortical rhythms. In this study we propose using source-space independent component analysis for identifying generators of resting-state cortical rhythms as recorded with ECoG and reconstructing their network structure. Their network structure is characterized by two kinds of connectivity: instantaneous correlations between band-limited amplitude envelopes and oscillatory phase-locking. Using simulated data, we find that the reconstruction of oscillatory phase-locking is more challenging than that of amplitude correlations, particularly for low signal-to-noise levels. Specifically, phase-lags can both be over- and underestimated as a consequence of first-order and higher-order volume-conduction effects, which troubles the interpretation of interaction measures based on imaginary phase-locking or coherence. The methodology is applied to resting-state beta (15-30 Hz) rhythms within the motor system of a macaque monkey and leads to the identification of a functional network of seven cortical generators that are distributed across the sensorimotor system. The spatial extent of the identified generators, together with consistent phase-lags, suggests that these rhythms can be viewed as being spatially continuous with complex dynamics including traveling waves. Our findings illustrate the level of spatial detail attainable with source-projected ECoG and motivates wider use of the methodology for studying resting-state as well as event-related cortical dynamics in macaque and human.

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Aberrant Interhemispheric Functional Organization in Children with Dyskinetic Cerebral Palsy

BioMed Research International ◽

10.1155/2019/4362539 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Yun Qin ◽

Bo Sun ◽

Huali Zhang ◽

Yanan Li ◽

Tao Zhang ◽

...

Keyword(s):

Cerebral Palsy ◽

Resting State ◽

Functional Organization ◽

Fundamental Principle ◽

Pathophysiological Mechanism ◽

Healthy Children ◽

Resting State Networks ◽

Frontoparietal Network ◽

Interhemispheric Connectivity ◽

Visual Motor

Background. Hemispheric asymmetry is one fundamental principle of neuronal organization. Interhemispheric connectivity and lateralization of intrinsic networks in the resting-state brain demonstrate the interhemispheric functional organization and can be affected by disease processes. This study aims to investigate the interhemispheric organization in children with dyskinetic cerebral palsy (DCP) based on resting-state functional MRI (fMRI). Methods. 24 children with DCP and 20 healthy children were included. Voxel-mirrored homotopic connectivity (VMHC) was calculated to detect the interhemispheric connectivity, and the lateralization of the resting-state networks was performed to examine the asymmetry of the intrinsic networks of brain. Results. Decreased interhemispheric connectivity was found at visual, motor, and motor-control related regions in children with DCP, while high cognitive related networks including the central executive network, the frontoparietal network, and the salience network represented decreased asymmetry in children with DCP. Abnormal VMHC in visual areas, as well as the altered lateralization in inferior parietal lobule and supplementary motor area, showed correlation with the gross motor function and activities of daily living in children with DCP. Conclusion. These findings indicate that the interhemispheric functional organization alteration exists in children with DCP, suggesting that abnormal interhemispheric interaction may be a pathophysiological mechanism of motor and cognitive dysfunction of CP.

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2092-P: Impact of Insulin Resistance on Response to a Meal by Salience, Executive Control, and Default Mode Resting State Networks in Humans

Diabetes ◽

10.2337/db19-2092-p ◽

2019 ◽

Vol 68 (Supplement 1) ◽

pp. 2092-P

Author(s):

LETICIA ESPOSITO SEWAYBRICKER ◽

SUSAN J. MELHORN ◽

MARY K. ASKREN ◽

MARY WEBB ◽

VIDHI TYAGI ◽

...

Keyword(s):

Insulin Resistance ◽

Executive Control ◽

Resting State ◽

Resting State Networks ◽

Default Mode

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Faculty Opinions recommendation of Electrophysiological signatures of resting state networks in the human brain.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1090485.543753 ◽

2007 ◽

Author(s):

Aapo Hyvärinen

Keyword(s):

Human Brain ◽

Resting State ◽

Resting State Networks

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Faculty Opinions recommendation of Arterial CO2 Fluctuations Modulate Neuronal Rhythmicity: Implications for MEG and fMRI Studies of Resting-State Networks.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.726643886.793524555 ◽

2016 ◽

Author(s):

James Duffin

Keyword(s):

Resting State ◽

Resting State Networks

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Intra and inter: Alterations in functional brain resting‐state networks after peripheral nerve injury

Brain and Behavior ◽

10.1002/brb3.1747 ◽

2020 ◽

Vol 10 (9) ◽

Author(s):

Xiang‐Xin Xing ◽

Xu‐Yun Hua ◽

Mou‐Xiong Zheng ◽

Zhen‐Zhen Ma ◽

Bei‐Bei Huo ◽

...

Keyword(s):

Peripheral Nerve ◽

Nerve Injury ◽

Resting State ◽

Peripheral Nerve Injury ◽

Resting State Networks ◽

Functional Brain

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Brainwide functional networks associated with anatomically- and functionally-defined hippocampal subfields using ultrahigh-resolution fMRI

Scientific Reports ◽

10.1038/s41598-021-90364-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Wei-Tang Chang ◽

Stephanie K. Langella ◽

Yichuan Tang ◽

Sahar Ahmad ◽

Han Zhang ◽

...

Keyword(s):

Resting State ◽

Functional Organization ◽

A Priori ◽

Longitudinal Axis ◽

Functional Networks ◽

Resting State Functional Connectivity ◽

Underlying Assumption ◽

Isotropic Resolution ◽

Hippocampal Subfields ◽

Fine Grained

AbstractThe hippocampus is critical for learning and memory and may be separated into anatomically-defined hippocampal subfields (aHPSFs). Hippocampal functional networks, particularly during resting state, are generally analyzed using aHPSFs as seed regions, with the underlying assumption that the function within a subfield is homogeneous, yet heterogeneous between subfields. However, several prior studies have observed similar resting-state functional connectivity (FC) profiles between aHPSFs. Alternatively, data-driven approaches investigate hippocampal functional organization without a priori assumptions. However, insufficient spatial resolution may result in a number of caveats concerning the reliability of the results. Hence, we developed a functional Magnetic Resonance Imaging (fMRI) sequence on a 7 T MR scanner achieving 0.94 mm isotropic resolution with a TR of 2 s and brain-wide coverage to (1) investigate the functional organization within hippocampus at rest, and (2) compare the brain-wide FC associated with fine-grained aHPSFs and functionally-defined hippocampal subfields (fHPSFs). This study showed that fHPSFs were arranged along the longitudinal axis that were not comparable to the lamellar structures of aHPSFs. For brain-wide FC, the fHPSFs rather than aHPSFs revealed that a number of fHPSFs connected specifically with some of the functional networks. Different functional networks also showed preferential connections with different portions of hippocampal subfields.

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