Aberrant Functional and Effective Connectivity of the Frontostriatal Network in Unilateral Acute Tinnitus Patients with Hearing Loss

Abstract Purpose: The present study combined resting-state functional connectivity (FC) and Granger causality analysis (GCA) to explore frontostriatal network dysfunction in unilateral acute tinnitus (AT) patients with hearing loss. Methods: The participants included 42 AT patients and 43 healthy control (HC) subjects who underwent resting-state functional magnetic resonance imaging (fMRI) scans. Based on the seed regions in the frontostriatal network, FC and GCA were conducted between the AT patients and HC subjects. Correlation analyses were used to examine correlations among altered FC values, GCA values, and clinical features in AT patients. Results: Compared with HCs, AT patients showed a general reduction in FC between the seed regions in the frontostriatal network and nonauditory areas, including the frontal cortices, midcingulate cortex (MCC) , supramarginal gyrus (SMG), and postcentral gyrus (PoCG) . Using the GCA algorithm, we detected abnormal effective connectivity (EC) in the inferior occipital gyrus (IOG), MCC, Cerebelum_Crus1, and PoCG. Furthermore, correlations between disrupted FC/EC and clinical characteristics, especially tinnitus distress-related characteristics, were found in AT patients. Conclusions: Our work demonstrated abnormal FC and EC between the frontostriatal network and several nonauditory regions in AT patients with hearing loss, suggesting that multiple large-scale network dysfunctions and interactions are involved in the perception of tinnitus. These findings not only enhance the current understanding of the frontostriatal network in tinnitus but also serve as a reminder of the importance of focusing on tinnitus at an early stage.

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Reconfiguration of directed functional connectivity among triple networks with aging: Considering the role of thalamo-cortical interactions

10.1101/827451 ◽

2019 ◽

Author(s):

Moumita Das ◽

Vanshika Singh ◽

Lucina Uddin ◽

Arpan Banerjee ◽

Dipanjan Roy

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Large Scale ◽

Effective Connectivity ◽

Network Connectivity ◽

Young Group ◽

Resting State Functional Connectivity ◽

Functional Changes ◽

Age Related ◽

Directional Connectivity

AbstractThe human brain undergoes significant structural and functional changes across the lifespan. Our current understanding of the underlying causal relationships of dynamical changes in functional connectivity with age is limited. On average, functional connectivity within resting-state networks (RSNs) weakens in magnitude, while connections between RSNs tend to increase with age. Recent studies show that effective connectivity within and between large scale resting-state functional networks changes over the healthy lifespan. The vast majority of previous studies have focused primarily on characterizing cortical networks, with little work exploring the influence of subcortical nodes such as the thalamus on large-scale network interactions across the lifespan. Using directed connectivity and weighted net causal outflow measures applied to resting-state fMRI data, we examine the age-related changes in both cortical and thalamocortical causal interactions within and between RSNs. The three core neurocognitive networks from the triple network theory (default mode: DMN, salience: SN, and central executive: CEN) were identified independently using ICA and spatial matching of hub regions with these important RSNs previously reported in the literature. Multivariate granger causal analysis (GCA) was performed to test for directional connectivity and weighted causal outflow between selected nodes of RSNs accounting for thalamo-cortical interactions. Firstly, we observe that within-network causal connections become progressively weaker with age, and network dynamics are substantially reconfigured via strong thalamic drive particularly in the young group. Our findings manifest stronger between-network directional connectivity, which is further strongly mediated by the SN in flexible co-ordination with the CEN, and DMN in the old group compared with the young group. Hence, causal within- and between- triple network connectivity largely reflects age-associated effects of resting-state functional connectivity. Thalamo-cortical causality effects on the triple networks with age were next explored. We discovered that left and right thalamus exhibit substantial interactions with the triple networks and play a crucial role in the reconfiguration of directed connections and within network causal outflow. The SN displayed directed functional connectivity in strongly driving both the CEN and DMN to a greater extent in the older group. Notably, these results were largely replicated on an independent dataset of matched young and old individuals. Our findings based on directed functional connectivity and weighted causal outflow measures strengthen the hypothesis that balancing within and between network connectivity is perhaps critical for the preservation and flexibility of cognitive functioning with aging.

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Reduced resting state functional connectivity with increasing age-related hearing loss and McGurk susceptibility

Scientific Reports ◽

10.1038/s41598-020-74012-0 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Alina Schulte ◽

Christiane M. Thiel ◽

Anja Gieseler ◽

Maike Tahden ◽

Hans Colonius ◽

...

Keyword(s):

Hearing Loss ◽

Functional Connectivity ◽

Resting State ◽

Mcgurk Effect ◽

Functional Coupling ◽

Resting State Functional Connectivity ◽

Visual Integration ◽

Age Related ◽

Hearing Thresholds ◽

Age Related Hearing Loss

Abstract Age-related hearing loss has been related to a compensatory increase in audio-visual integration and neural reorganization including alterations in functional resting state connectivity. How these two changes are linked in elderly listeners is unclear. The current study explored modulatory effects of hearing thresholds and audio-visual integration on resting state functional connectivity. We analysed a large set of resting state data of 65 elderly participants with a widely varying degree of untreated hearing loss. Audio-visual integration, as gauged with the McGurk effect, increased with progressing hearing thresholds. On the neural level, McGurk illusions were negatively related to functional coupling between motor and auditory regions. Similarly, connectivity of the dorsal attention network to sensorimotor and primary motor cortices was reduced with increasing hearing loss. The same effect was obtained for connectivity between the salience network and visual cortex. Our findings suggest that with progressing untreated age-related hearing loss, functional coupling at rest declines, affecting connectivity of brain networks and areas associated with attentional, visual, sensorimotor and motor processes. Especially connectivity reductions between auditory and motor areas were related to stronger audio-visual integration found with increasing hearing loss.

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Graph slepians to probe into large-scale network organization of resting-state functional connectivity

2017 51st Asilomar Conference on Signals, Systems, and Computers ◽

10.1109/acssc.2017.8335615 ◽

2017 ◽

Author(s):

Maria Giulia Preti ◽

Dimitri Van De Ville

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Large Scale ◽

Network Organization ◽

Resting State Functional Connectivity ◽

Large Scale Network ◽

Scale Network

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Stroke-related alterations in inter-areal communication revealed via Granger causality analysis

10.1101/2021.01.04.425190 ◽

2021 ◽

Author(s):

Michele Allegra ◽

Chiara Favaretto ◽

Nicholas Metcalf ◽

Maurizio Corbetta ◽

Andrea Brovelli

Keyword(s):

Functional Connectivity ◽

Granger Causality ◽

Resting State ◽

Information Transfer ◽

Large Scale ◽

Functional Organization ◽

Information Flows ◽

Causality Analysis ◽

Stroke Patients ◽

Granger Causality Analysis

ABSTRACTNeuroimaging and neurological studies suggest that stroke is a brain network syndrome. While causing local ischemia and cell damage at the site of injury, stroke strongly perturbs the functional organization of brain networks at large. Critically, functional connectivity abnormalities parallel both behavioral deficits and functional recovery across different cognitive domains. However, the reasons for such relations remain poorly understood. Here, we tested the hypothesis that alterations in inter-areal communication underlie stroke-related modulations in functional connectivity (FC). To this aim, we used resting-state fMRI and Granger causality analysis to quantify information transfer between brain areas and its alteration in stroke. Two main large-scale anomalies were observed in stroke patients. First, inter-hemispheric information transfer was strongly decreased with respect to healthy controls. Second, information transfer within the affected hemisphere, and from the affected to the intact hemisphere was reduced. Both anomalies were more prominent in resting-state networks related to attention and language, and they were correlated with impaired performance in several behavioral domains. Overall, our results support the hypothesis that stroke perturbs inter-areal communication within and across hemispheres, and suggest novel therapeutic approaches aimed at restoring normal information flow.SIGNIFICANCE STATEMENTA thorough understanding of how stroke perturbs brain function is needed to improve recovery from the severe neurological syndromes affecting stroke patients. Previous resting-state neuroimaging studies suggested that interaction between hemispheres decreases after stroke, while interaction between areas of the same hemisphere increases. Here, we used Granger causality to reconstruct information flows in the brain at rest, and analyze how stroke perturbs them. We showed that stroke causes a global reduction of inter-hemispheric communication, and an imbalance between the intact and the affected hemisphere: information flows within and from the latter are impaired. Our results may inform the design of stimulation therapies to restore the functional balance lost after stroke.

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Altered hypothalamus functional connectivity with limbic system in fibromyalgia and the modulation effect of intervention

10.21203/rs.2.20627/v1 ◽

2020 ◽

Author(s):

Jian Kong ◽

Yiting Huang ◽

Jiao Liu ◽

Siyi Yu ◽

Ming Cheng ◽

...

Keyword(s):

Functional Connectivity ◽

Limbic System ◽

Resting State ◽

Tai Chi ◽

Effective Connectivity ◽

Resting State Fmri ◽

Trial Registration ◽

Modulation Effect ◽

Resting State Functional Connectivity ◽

Before And After

Abstract Background: This study aims to investigate the resting state functional connectivity (rsFC) changes of the hypothalamus in Fibromyalgia patients and the modulation effect of effective treatments. Methods: Fibromyalgia patients and matched healthy controls (HC’s) were recruited. Resting state fMRI data were collected from fibromyalgia patients before and after a 12-week Tai Chi intervention and once from HC’s. Results: Data analysis showed that fibromyalgia patients displayed significantly decreased medial hypothalamus (MH) rsFC with the thalamus and amygdala when compared to HC’s at baseline. After the intervention, fibromyalgia patients showed increased (normalized) MH rsFC in the thalamus and amygdala. Effective connectivity analysis showed disrupted MH and thalamus interaction in fibromyalgia, which nonetheless could be partially restored by Tai Chi. Conclusions: Elucidating the role of the diencephalon and limbic system in the pathophysiology and development of fibromyalgia may facilitate the development of new treatment methods for this prevalent disorder. Trial registration: Trial registration ClinicalTrials.gov Identifier: NCT02407665. Registered 3 April 2015 - Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02407665

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Treatment of age-related hearing loss alters audiovisual integration and resting-state functional connectivity: A randomized controlled pilot trial

10.31219/osf.io/48bpt ◽

2021 ◽

Author(s):

Stephanie Rosemann ◽

Anja Gieseler ◽

Maike Tahden ◽

Hans Colonius ◽

Christiane Thiel

Keyword(s):

Hearing Loss ◽

Resting State ◽

Hearing Aid ◽

Brain Connectivity ◽

Audiovisual Integration ◽

Resting State Functional Connectivity ◽

Functional Brain ◽

Hearing Aid Use ◽

Age Related ◽

Age Related Hearing Loss

Untreated age-related hearing loss increases audiovisual integration and impacts resting state functional brain connectivity. It is unclear whether compensation with hearing aids is able to alter audiovisual integration and resting state functional brain connectivity. We conducted a randomized controlled pilot study to investigate how the McGurk illusion, a common measure for audiovisual integration, and resting state functional brain connectivity of the auditory cortex are altered by six-month hearing aid use. Thirty-two older participants with slight-to-moderate, symmetric, age-related hearing loss were allocated to a treatment or waiting control group and measured one week before and six months after hearing aid fitting with functional magnetic resonance imaging. Our results showed that a hearing aid use of six months was associated with a decrease in resting state functional connectivity between the auditory cortex and the fusiform gyrus and that this decrease was related to an increase of perceived McGurk illusions. Our study, therefore, suggests that even short-term hearing aid use alters audiovisual integration and functional brain connectivity between auditory and visual cortices.

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Attention network modulation via tRNS correlates with attention gain

eLife ◽

10.7554/elife.63782 ◽

2021 ◽

Vol 10 ◽

Author(s):

Federica Contò ◽

Grace Edwards ◽

Sarah Tyler ◽

Danielle Parrott ◽

Emily Grossman ◽

...

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Large Scale ◽

Random Noise ◽

Cognitive Capacity ◽

Resting State Functional Connectivity ◽

Attention Network ◽

Transcranial Random Noise Stimulation ◽

The Impact ◽

Behavioral Improvement

Transcranial random noise stimulation (tRNS) can enhance vision in the healthy and diseased brain. Yet, the impact of multi-day tRNS on large-scale cortical networks is still unknown. We investigated the impact of tRNS coupled with behavioral training on resting-state functional connectivity and attention. We trained human subjects for 4 consecutive days on two attention tasks, while receiving tRNS over the intraparietal sulci, the middle temporal areas, or Sham stimulation. We measured resting-state functional connectivity of nodes of the dorsal and ventral attention network (DVAN) before and after training. We found a strong behavioral improvement and increased connectivity within the DVAN after parietal stimulation only. Crucially, behavioral improvement positively correlated with connectivity measures. We conclude changes in connectivity are a marker for the enduring effect of tRNS upon behavior. Our results suggest that tRNS has strong potential to augment cognitive capacity in healthy individuals and promote recovery in the neurological population.

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Tinnitus distress is linked to enhanced resting-state functional connectivity from the limbic system to the auditory cortex

Human Brain Mapping ◽

10.1002/hbm.23525 ◽

2017 ◽

Vol 38 (5) ◽

pp. 2384-2397 ◽

Cited By ~ 43

Author(s):

Yu-Chen Chen ◽

Wenqing Xia ◽

Huiyou Chen ◽

Yuan Feng ◽

Jin-Jing Xu ◽

...

Keyword(s):

Functional Connectivity ◽

Auditory Cortex ◽

Limbic System ◽

Resting State ◽

Resting State Functional Connectivity ◽

Tinnitus Distress

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Large-scale DCMs for resting-state fMRI

Network Neuroscience ◽

10.1162/netn_a_00015 ◽

2017 ◽

Vol 1 (3) ◽

pp. 222-241 ◽

Cited By ~ 63

Author(s):

Adeel Razi ◽

Mohamed L. Seghier ◽

Yuan Zhou ◽

Peter McColgan ◽

Peter Zeidman ◽

...

Keyword(s):

Functional Connectivity ◽

Resting State ◽

Large Scale ◽

Effective Connectivity ◽

Directed Graphs ◽

Resting State Fmri ◽

Causal Modeling ◽

Large Graphs ◽

Model Inversion ◽

Graph Theoretic

This paper considers the identification of large directed graphs for resting-state brain networks based on biophysical models of distributed neuronal activity, that is, effective connectivity. This identification can be contrasted with functional connectivity methods based on symmetric correlations that are ubiquitous in resting-state functional MRI (fMRI). We use spectral dynamic causal modeling (DCM) to invert large graphs comprising dozens of nodes or regions. The ensuing graphs are directed and weighted, hence providing a neurobiologically plausible characterization of connectivity in terms of excitatory and inhibitory coupling. Furthermore, we show that the use of Bayesian model reduction to discover the most likely sparse graph (or model) from a parent (e.g., fully connected) graph eschews the arbitrary thresholding often applied to large symmetric (functional connectivity) graphs. Using empirical fMRI data, we show that spectral DCM furnishes connectivity estimates on large graphs that correlate strongly with the estimates provided by stochastic DCM. Furthermore, we increase the efficiency of model inversion using functional connectivity modes to place prior constraints on effective connectivity. In other words, we use a small number of modes to finesse the potentially redundant parameterization of large DCMs. We show that spectral DCM—with functional connectivity priors—is ideally suited for directed graph theoretic analyses of resting-state fMRI. We envision that directed graphs will prove useful in understanding the psychopathology and pathophysiology of neurodegenerative and neurodevelopmental disorders. We will demonstrate the utility of large directed graphs in clinical populations in subsequent reports, using the procedures described in this paper.

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