scholarly journals Reduction of Interhemispheric Functional Brain Connectivity in Early Blindness: A Resting-State fMRI Study

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Fen Hou ◽  
Xia Liu ◽  
Zhifeng Zhou ◽  
Jingyi Zhou ◽  
Hengguo Li
Keyword(s):  
Functional Connectivity ◽  
Resting State ◽  
Brain Connectivity ◽  
Gray Matter Volume ◽  
Resting State Fmri ◽  
Association Cortex ◽  
Middle Temporal ◽  
And Gender ◽  
The Individual ◽  
Early Blindness

Objective. The purpose of this study was to investigate the resting-state interhemispheric functional connectivity in early blindness by using voxel-mirrored homotopic connectivity (VMHC). Materials and Methods. Sixteen early blind patients (EB group) and sixteen age- and gender-matched sighted control volunteers (SC group) were recruited in this study. We used VMHC to identify brain areas with significant differences in functional connectivity between different groups and used voxel-based morphometry (VBM) to calculate the individual gray matter volume (GMV). Results. VMHC analysis showed a significantly lower connectivity in primary visual cortex, visual association cortex, and somatosensory association cortex in EB group compared to sighted controls. Additionally, VBM analysis revealed that GMV was reduced in the left lateral calcarine cortices in EB group compared to sighted controls, while it was increased in the left lateral middle occipital gyri. Statistical analysis showed the duration of blindness negatively correlated with VMHC in the bilateral middle frontal gyri, middle temporal gyri, and inferior temporal gyri. Conclusions. Our findings help elucidate the pathophysiological mechanisms of EB. The interhemispheric functional connectivity was impaired in EB patients. Additionally, the middle frontal gyri, middle temporal gyri, and inferior temporal gyri may be potential target regions for rehabilitation.

scholarly journals Functional Alterations in Cerebellar Functional Connectivity in Anxiety Disorders

2020 ◽  
Author(s):  
Yoon Ji Lee ◽  
Xavier Guell ◽  
Nicholas A. Hubbard ◽  
Viviana Siless ◽  
Isabelle R. Frosch ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Anxiety Disorders ◽  
Resting State ◽  
Brain Connectivity ◽  
Resting State Fmri ◽  
Cortical Activation ◽  
Self Report ◽  
Resting State Functional Connectivity ◽  
Adolescent Anxiety ◽  
And Gender

AbstractAdolescents with anxiety disorders exhibit excessive emotional and somatic arousal. Neuroimaging studies have shown abnormal cerebral cortical activation and connectivity in this patient population. The specific role of cerebellar output circuitry, specifically the dentate nuclei (DN), in adolescent anxiety disorders remains largely unexplored. Resting-state functional connectivity analyses have parcellated the DN, the major output nuclei of the cerebellum, into three functional territories (FTs) that include default-mode, salience-motor, and visual networks. The objective of this study was to understand whether FTs of the DN are implicated in adolescent anxiety disorders. Forty-one adolescents (mean age 15.19 ± 0.82, 26 females) with one or more anxiety disorders and 55 age- and gender-matched healthy controls completed resting-state fMRI scans and a self-report survey on anxiety symptoms. Seed-to-voxel functional connectivity analyses were performed using the FTs from DN parcellation. Brain connectivity metrics were then correlated with State-Trait Anxiety Inventory (STAI) measures within each group. Adolescents with an anxiety disorder showed significant hyperconnectivity between salience-motor DN FT and cerebral cortical salience-motor regions compared to controls. Salience-motor FT connectivity with cerebral cortical sensorimotor regions was significantly correlated with STAI-trait scores in HC (R2 = 0.41). Here, we report DN functional connectivity differences in adolescents diagnosed with anxiety, as well as in HC with variable degrees of anxiety traits. These observations highlight the relevance of DN as a potential clinical and sub-clinical marker of anxiety.

scholarly journals Resting-state brain activity can predict target-independent aptitude in fMRI-neurofeedback training

2021 ◽  
Author(s):  
Takashi Nakano ◽  
Masahiro Takamura ◽  
Haruki Nishimura ◽  
Maro Machizawa ◽  
Naho Ichikawa ◽  
...  
Keyword(s):  
Resting State ◽  
Brain Connectivity ◽  
Brain Activity ◽  
Resting State Fmri ◽  
Brain Regions ◽  
Posterior Cingulate Cortex ◽  
Fmri Data ◽  
Independent Test ◽  
The Individual ◽  
The Brain

AbstractNeurofeedback (NF) aptitude, which refers to an individual’s ability to change its brain activity through NF training, has been reported to vary significantly from person to person. The prediction of individual NF aptitudes is critical in clinical NF applications. In the present study, we extracted the resting-state functional brain connectivity (FC) markers of NF aptitude independent of NF-targeting brain regions. We combined the data in fMRI-NF studies targeting four different brain regions at two independent sites (obtained from 59 healthy adults and six patients with major depressive disorder) to collect the resting-state fMRI data associated with aptitude scores in subsequent fMRI-NF training. We then trained the regression models to predict the individual NF aptitude scores from the resting-state fMRI data using a discovery dataset from one site and identified six resting-state FCs that predicted NF aptitude. Next we validated the prediction model using independent test data from another site. The result showed that the posterior cingulate cortex was the functional hub among the brain regions and formed predictive resting-state FCs, suggesting NF aptitude may be involved in the attentional mode-orientation modulation system’s characteristics in task-free resting-state brain activity.

scholarly journals Functional Brain Connectivity Patterns Associated with Visual Hallucinations in Dementia with Lewy Bodies

2021 ◽  
pp. 1-10
Author(s):  
Stefania Pezzoli ◽  
Matteo De Marco ◽  
Giovanni Zorzi ◽  
Annachiara Cagnin ◽  
Annalena Venneri
Keyword(s):  
Functional Connectivity ◽  
Resting State ◽  
Dementia With Lewy Bodies ◽  
Brain Connectivity ◽  
Lewy Bodies ◽  
Resting State Fmri ◽  
Group Differences ◽  
Visual Hallucinations ◽  
Functional Brain ◽  
Functional Brain Networks

Background: The presence of recurrent, complex visual hallucinations (VH) is among the core clinical features of dementia with Lewy bodies (DLB). It has been proposed that VH arise from a disrupted organization of functional brain networks. However, studies are still limited, especially investigating the resting-state functional brain features underpinning VH in patients with dementia. Objective: The aim of the present pilot study was to investigate whether there were any alterations in functional connectivity associated with VH in DLB. Methods: Seed-based analyses and independent component analysis (ICA) of resting-state fMRI scans were carried out to explore differences in functional connectivity between DLB patients with and without VH. Results: Seed-based analyses reported decreased connectivity of the lateral geniculate nucleus, the superior parietal lobule and the putamen with the medial frontal gyrus in DLB patients with VH. Visual areas showed a pattern of both decreased and increased functional connectivity. ICA revealed between-group differences in the default mode network (DMN). Conclusion: Functional connectivity analyses suggest dysfunctional top-down and bottom-up processes and DMN-related alterations in DLB patients with VH. These impairments might foster the generation of false visual images that are misinterpreted, ultimately resulting in VH.

scholarly journals Strengthened thalamoparietal functional connectivity in patients with hemifacial spasm: a cross-sectional resting-state fMRI study

2020 ◽  
Vol 93 (1108) ◽  
pp. 20190887 ◽  
Author(s):  
Xuan Niu ◽  
Hui Xu ◽  
Chenguang Guo ◽  
Tong Yang ◽  
Dustin Kress ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Hemifacial Spasm ◽  
Resting State ◽  
Resting State Fmri ◽  
Association Cortex ◽  
Resting State Networks ◽  
Supramarginal Gyrus ◽  
Resting State Functional Connectivity ◽  
Cross Sectional ◽  
The Right

Objective: In spite of the well-known importance of thalamus in hemifacial spasm (HFS), the thalamic resting-state networks in HFS is still rarely mentioned. This study aimed to investigate resting-state functional connectivity (FC) of the thalamus in HFS patients and examine its association with clinical measures. Methods: 25 HFS patients and 28 matched healthy controls underwent functional MRI at rest. Using the left and right thalamus as seed regions respectively, we compared the thalamic resting-state networks between patient and control groups using two independent sample t-test. Results: Compared with controls, HFS patients exhibited strengthened bilateral thalamus-seeded FC with the parietal cortex. Enhanced FC between right thalamus and left somatosensory association cortex was linked to worse motor disturbance, and the increased right thalamus-right supramarginal gyrus connection were correlated with improvement of affective symptoms. Conclusion: Our findings indicate that the right thalamus–left somatosensory association cortex hyperconnectivity may represent the underlying neuroplasticity related to sensorimotor dysfunction. In addition, the upregulated FC between the right thalamus and right supramarginal gyrus in HFS, is part of the thalamo-default mode network pathway involved in emotional adaptation. Advances in knowledge: This study provides new insights on the integrative role of thalamo-parietal connectivity, which participates in differential neural circuitry as a mechanism underlying motor and emotional functions in HFS patients.

scholarly journals Lasting effects of a single psilocybin dose on resting-state functional connectivity in healthy individuals

2021 ◽  
Author(s):  
Drummond E-Wen McCulloch ◽  
Martin Korsbak Madsen ◽  
Dea Siggard Stenbæk ◽  
Sara Kristiansen ◽  
Brice Ozenne ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Resting State ◽  
Clinical Symptoms ◽  
Brain Connectivity ◽  
Well Being ◽  
Resting State Fmri ◽  
Long Term Effects ◽  
Resting State Functional Connectivity ◽  
Positive Effects ◽  
Personality Changes

ABSTRACTBackgroundPsilocybin is a psychedelic drug that has shown lasting positive effects on clinical symptoms and self-reported well-being following a single dose. There has been little research into the long-term effects of psilocybin on brain connectivity in humans.AimsEvaluate changes in resting-state functional connectivity (RSFC) at one-week and three-months after one psilocybin dose in 10 healthy psychedelic-naïve volunteers and explore associations between change in RSFC and related measures.MethodsParticipants received 0.2-0.3 mg/kg psilocybin in a controlled setting. Participants completed resting-state fMRI scans at baseline, one-week and three-months post-administration and [11C]Cimbi-36 PET scans at baseline and one-week. We examined changes in within-network, between-network and region-to-region RSFC. We explored associations between changes in RSFC and psilocybin-induced phenomenology as well as changes in psychological measures and neocortex serotonin 2A receptor binding.ResultsPsilocybin was well tolerated and produced positive changes in well-being. At one-week only, executive control network (ECN) RSFC was significantly decreased (Cohen’s d=-1.73, pFWE=0.010). We observed no other significant changes in RSFC at one-week or three-months, nor changes in region-to-region RSFC. Exploratory analyses indicated that decreased ECN RSFC at one-week predicted increased mindfulness at three-months (r =-0.65).ConclusionsThese findings in a small cohort indicate that psilocybin affects ECN function within the psychedelic “afterglow” period. Our findings implicate ECN modulation as mediating psilocybin-induced, long-lasting increases in mindfulness. Although our findings implicate a neural pathway mediating lasting psilocybin effects, it is notable that changes in neuroimaging measures at three-months, when personality changes are observed, remain to be identified.

scholarly journals Unsupervised clustering of track-weighted dynamic functional connectivity reveals white matter substrates of functional connectivity dynamics

2021 ◽  
Author(s):  
Gianpaolo Antonio Basile ◽  
Salvatore Bertino ◽  
Victor Nozais ◽  
Alessia Bramanti ◽  
Rosella Ciurleo ◽  
...  
Keyword(s):  
White Matter ◽  
Functional Connectivity ◽  
Resting State ◽  
Time Course ◽  
Brain Connectivity ◽  
Structural Connectivity ◽  
Resting State Fmri ◽  
Dynamic Changes ◽  
Dynamic Functional Connectivity ◽  
Dynamic Connectivity

AbstractThe contribution of structural connectivity to functional connectivity dynamics is still far from being fully elucidated. Herein, we applied track-weighted dynamic functional connectivity (tw-dFC), a model integrating structural, functional, and dynamic connectivity, on high quality diffusion weighted imaging and resting-state fMRI data from two independent repositories. The tw-dFC maps were analyzed using independent component analysis, aiming at identifying spatially independent white matter components which support dynamic changes in functional connectivity. Each component consisted of a spatial map of white matter bundles that show consistent fluctuations in functional connectivity at their endpoints, and a time course representative of such functional activity. These components show high intra-subject, inter-subject, and inter-cohort reproducibility. We provided also converging evidence that functional information about white matter activity derived by this method can capture biologically meaningful features of brain connectivity organization, as well as predict higher-order cognitive performance.

scholarly journals The individual functional connectome is unique and stable over months to years

2017 ◽  
Author(s):  
Corey Horien ◽  
Xilin Shen ◽  
Dustin Scheinost ◽  
R. Todd Constable
Keyword(s):  
Individual Differences ◽  
Functional Connectivity ◽  
Resting State ◽  
Resting State Fmri ◽  
List Type ◽  
Functional Connectome ◽  
Wide Range ◽  
The Individual ◽  
Brain Functional Connectivity ◽  
Parietal Cortices

AbstractFunctional connectomes computed from fMRI provide a means to characterize individual differences in the patterns of BOLD synchronization across regions of the entire brain. Using four resting-state fMRI datasets with a wide range of ages, we show that individual differences of the functional connectome are stable across three months to three years. Medial frontal and frontoparietal networks appear to be both unique and stable, resulting in high ID rates, as did a combination of these two networks. We conduct analyses demonstrating that these results are not driven by head motion. We also show that the edges demonstrating the most individualized features tend to connect nodes in the frontal and parietal cortices, while edges contributing the least tend to connect cross-hemispheric homologs. Our results demonstrate that the functional connectome is stable across years and is not an idiosyncratic aspect of a specific dataset, but rather reflects stable individual differences in the functional connectivity of the brain.Research highlightsWhole-brain functional connectivity profiles obtained from four resting-state fMRI datasets are unique and stable across 3 months-3 years in adolescents, young adults, and older adultsMedial frontal and frontoparietal networks tended to be both unique and stableIndividual edges in the frontal and parietal cortices tended to be most discriminative of individual subjects

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