Disrupted neural activity in unilateral vascular pulsatile tinnitus patients in the early stage of disease: Evidence from resting-state fMRI

White matter hyperintensity (WMH) is common in healthy adults in their 60s and can be seen as early as in their 30s and 40s. Alterations in the brain structural and functional profiles in adults with WMH have been repeatedly studied but with a focus on late-stage WMH. To date, structural and functional MRI profiles during the very early stage of WMH remain largely unexplored. To address this, we investigated multimodal MRI (structural, diffusion, and resting-state functional MRI) profiles of community-dwelling asymptomatic adults with very early-stage WMH relative to age-, sex-, and education-matched non-WMH controls. The comparative results showed significant age-related and age-independent changes in structural MRI-based morphometric measures and resting-state fMRI-based measures in a set of specific gray matter (GM) regions but no global white matter changes. The observed structural and functional anomalies in specific GM regions in community-dwelling asymptomatic adults with very early-stage WMH provide novel data regarding very early-stage WMH and enhance understanding of the pathogenesis of WMH.

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State-Related Alterations of Spontaneous Neural Activity in Current and Remitted Depression Revealed by Resting-State fMRI

Frontiers in Psychology ◽

10.3389/fpsyg.2019.00245 ◽

2019 ◽

Vol 10 ◽

Cited By ~ 7

Author(s):

Chang Cheng ◽

Daifeng Dong ◽

Yali Jiang ◽

Qingsen Ming ◽

Xue Zhong ◽

...

Keyword(s):

Neural Activity ◽

Resting State ◽

Resting State Fmri ◽

Spontaneous Neural Activity ◽

Remitted Depression

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Abnormal resting-state connectivity of motor and cognitive networks in early manifest Huntington's disease

Psychological Medicine ◽

10.1017/s0033291714000579 ◽

2014 ◽

Vol 44 (15) ◽

pp. 3341-3356 ◽

Cited By ~ 30

Author(s):

R. C. Wolf ◽

F. Sambataro ◽

N. Vasic ◽

M. S. Depping ◽

P. A. Thomann ◽

...

Keyword(s):

Huntington's Disease ◽

Huntington’S Disease ◽

Motor Function ◽

Neural Activity ◽

Resting State ◽

Brain Atrophy ◽

Clinical Symptoms ◽

Resting State Fmri ◽

Cognitive Networks ◽

The Impact

Background.Functional magnetic resonance imaging (fMRI) of multiple neural networks during the brain's ‘resting state’ could facilitate biomarker development in patients with Huntington's disease (HD) and may provide new insights into the relationship between neural dysfunction and clinical symptoms. To date, however, very few studies have examined the functional integrity of multiple resting state networks (RSNs) in manifest HD, and even less is known about whether concomitant brain atrophy affects neural activity in patients.Method.Using MRI, we investigated brain structure and RSN function in patients with early HD (n = 20) and healthy controls (n = 20). For resting-state fMRI data a group-independent component analysis identified spatiotemporally distinct patterns of motor and prefrontal RSNs of interest. We used voxel-based morphometry to assess regional brain atrophy, and ‘biological parametric mapping’ analyses to investigate the impact of atrophy on neural activity.Results.Compared with controls, patients showed connectivity changes within distinct neural systems including lateral prefrontal, supplementary motor, thalamic, cingulate, temporal and parietal regions. In patients, supplementary motor area and cingulate cortex connectivity indices were associated with measures of motor function, whereas lateral prefrontal connectivity was associated with cognition.Conclusions.This study provides evidence for aberrant connectivity of RSNs associated with motor function and cognition in early manifest HD when controlling for brain atrophy. This suggests clinically relevant changes of RSN activity in the presence of HD-associated cortical and subcortical structural abnormalities.

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Hierarchical disruption in the cortex of anesthetized monkeys as a new signature of consciousness loss

10.1101/2020.06.04.133538 ◽

2020 ◽

Author(s):

Camilo Miguel Signorelli ◽

Lynn Uhrig ◽

Morten Kringelbach ◽

Bechir Jarraya ◽

Gustavo Deco

Keyword(s):

Neural Activity ◽

Resting State ◽

Resting State Fmri ◽

Hierarchical Organization ◽

Brain Dynamics ◽

Depth Of Anesthesia ◽

Functional Changes ◽

Cortical Hierarchy ◽

Brain States ◽

Structure Similarity

AbstractAnesthesia induces a reconfiguration of the repertoire of functional brain states leading to a high function-structure similarity. However, it is unclear how these functional changes lead to loss of consciousness. Here we suggest that the mechanism of conscious access is related to a general dynamical rearrangement of the intrinsic hierarchical organization of the cortex. To measure cortical hierarchy, we applied the Intrinsic Ignition analysis to resting-state fMRI data acquired in awake and anesthetized macaques. Our results reveal the existence of spatial and temporal hierarchical differences of neural activity within the macaque cortex, with a strong modulation by the depth of anesthesia and the employed anesthetic agent. Higher values of Intrinsic Ignition correspond to rich and flexible brain dynamics whereas lower values correspond to poor and rigid, structurally driven brain dynamics. Moreover, spatial and temporal hierarchical dimensions are disrupted in a different manner, involving different hierarchical brain networks. All together suggest that disruption of brain hierarchy is a new signature of consciousness loss.

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Different dynamic resting state fMRI patterns are linked to different frequencies of neural activity

Journal of Neurophysiology ◽

10.1152/jn.00235.2015 ◽

2015 ◽

Vol 114 (1) ◽

pp. 114-124 ◽

Cited By ~ 22

Author(s):

Garth John Thompson ◽

Wen-Ju Pan ◽

Shella Dawn Keilholz

Keyword(s):

Neural Activity ◽

Attention Deficit Disorder ◽

Resting State ◽

Low Frequency ◽

Resting State Fmri ◽

Periodic Patterns ◽

Limited Power ◽

Band Limited ◽

Additional Support ◽

Network Mapping

Resting state functional magnetic resonance imaging (rsfMRI) results have indicated that network mapping can contribute to understanding behavior and disease, but it has been difficult to translate the maps created with rsfMRI to neuroelectrical states in the brain. Recently, dynamic analyses have revealed multiple patterns in the rsfMRI signal that are strongly associated with particular bands of neural activity. To further investigate these findings, simultaneously recorded invasive electrophysiology and rsfMRI from rats were used to examine two types of electrical activity (directly measured low-frequency/infraslow activity and band-limited power of higher frequencies) and two types of dynamic rsfMRI (quasi-periodic patterns or QPP, and sliding window correlation or SWC). The relationship between neural activity and dynamic rsfMRI was tested under three anesthetic states in rats: dexmedetomidine and high and low doses of isoflurane. Under dexmedetomidine, the lightest anesthetic, infraslow electrophysiology correlated with QPP but not SWC, whereas band-limited power in higher frequencies correlated with SWC but not QPP. Results were similar under isoflurane; however, the QPP was also correlated to band-limited power, possibly due to the burst-suppression state induced by the anesthetic agent. The results provide additional support for the hypothesis that the two types of dynamic rsfMRI are linked to different frequencies of neural activity, but isoflurane anesthesia may make this relationship more complicated. Understanding which neural frequency bands appear as particular dynamic patterns in rsfMRI may ultimately help isolate components of the rsfMRI signal that are of interest to disorders such as schizophrenia and attention deficit disorder.

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Abnormal Baseline Brain Activity in Patients with Pulsatile Tinnitus: A Resting-State fMRI Study

Neural Plasticity ◽

10.1155/2014/549162 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10 ◽

Cited By ~ 13

Author(s):

Lv Han ◽

Liu Zhaohui ◽

Yan Fei ◽

Li Ting ◽

Zhao Pengfei ◽

...

Keyword(s):

Resting State ◽

Structural Changes ◽

Brain Activity ◽

Inferior Frontal Gyrus ◽

Low Frequency ◽

Resting State Fmri ◽

Pulsatile Tinnitus ◽

Spontaneous Brain Activity ◽

Fmri Study ◽

The Brain

Numerous investigations studying the brain functional activity of the tinnitus patients have indicated that neurological changes are important findings of this kind of disease. However, the pulsatile tinnitus (PT) patients were excluded in previous studies because of the totally different mechanisms of the two subtype tinnitus. The aim of this study is to investigate whether altered baseline brain activity presents in patients with PT using resting-state functional magnetic resonance imaging (rs-fMRI) technique. The present study used unilateral PT patients (n=42) and age-, sex-, and education-matched normal control subjects (n=42) to investigate the changes in structural and amplitude of low-frequency (ALFF) of the brain. Also, we analyzed the relationships between these changes with clinical data of the PT patients. Compared with normal controls, PT patients did not show any structural changes. PT patients showed significant increased ALFF in the bilateral precuneus, and bilateral inferior frontal gyrus (IFG) and decreased ALFF in multiple occipital areas. Moreover, the increased THI score and PT duration was correlated with increased ALFF in precuneus and bilateral IFG. The abnormalities of spontaneous brain activity reflected by ALFF measurements in the absence of structural changes may provide insights into the neural reorganization in PT patients.

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