Abstract TP57: Altered Functional Connectivity in Transient Ischemic Attack Patients

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Michael S Stringer ◽  
Ourania Varsou ◽  
Catarina Fernandes ◽  
Christian Schwarzbauer ◽  
Mary J MacLeod
Keyword(s):  
Functional Connectivity ◽  
Control Group ◽  
Healthy Controls ◽  
Sensorimotor Network ◽  
Visual Component ◽  
Transient Ischaemic Attacks ◽  
Symptom Profile ◽  
Clinical Magnetic Resonance Imaging ◽  
Magnetic Resonance Imaging Mri ◽  
The Right

Introduction: The pathophysiology and sequelae of transient ischaemic attacks (TIA) merit further study,. Particular challenges arise from the on-going debate on diagnostic criteria and the fact that few studies use the modern tissue-based definition. Differences in functional connectivity have previously been identified in a number of conditions, including stroke, have been implicated in the symptom profile and are known to vary during recovery. In this pilot study we investigate whether there were functional connectivity differences between TIA patients and healthy controls. Methods: Patients were referred for a standard clinical magnetic resonance imaging (MRI) neurovascular protocol, with the addition of a resting state functional MRI (fMRI) sequence. Eight patients diagnosed with a TIA (4 women, 57±9) were recruited, along with eight healthy controls (4 women, 30±5). Independent component analysis was used to isolate the networks before performing non-parametric two-sample t-test using both threshold-free cluster enhancement (TFCE) and voxel-wise statistics. Results: Significant differences (p<0.05, FWE-corrected) emerged using TFCE, in particular increased connectivity was noted in the mid-cingulate area with contrasting decreases in the cerebellum within the sensorimotor network. Additionally clusters of decreased connectivity were noted in the right insula in an attentional component, the pre-cuneus within the default mode network and the supplementary motor area in a visual component. No significant differences between the TIA and control group were above the threshold using voxel-wise statistics. Conclusion: In line with previous research in groups of stroke patients, this study has identified evidence of differences in neural connectivity associated with TIA, which cannot be explained by age. Differences in the sensorimotor network may be linked to the symptoms experienced by patients, with the mid-cingluate area being implicated in memory and learning. Alterations in functional connectivity may be relevant for recovery, including the on-going cognitive deficits reported in TIA patients. These findings suggest an important area for further research with a larger cohort.

scholarly journals Voxel-Wise Brain-Wide Functional Connectivity Abnormalities in Patients with Primary Blepharospasm at Rest

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Pan Pan ◽  
Shubao Wei ◽  
Huabing Li ◽  
Yangpan Ou ◽  
Feng Liu ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Anterior Cingulate ◽  
Support Vector ◽  
Pathophysiological Mechanism ◽  
Precentral Gyrus ◽  
Healthy Controls ◽  
Sensorimotor Network ◽  
Specificity And Sensitivity ◽  
Postcentral Gyrus ◽  
The Right

Background. Primary blepharospasm (BSP) is one of the most common focal dystonia and its pathophysiological mechanism remains unclear. An unbiased method was used in patients with BSP at rest to observe voxel-wise brain-wide functional connectivity (FC) changes. Method. A total of 48 subjects, including 24 untreated patients with BSP and 24 healthy controls, were recruited to undergo functional magnetic resonance imaging (fMRI). The method of global-brain FC (GFC) was adopted to analyze the resting-state fMRI data. We designed the support vector machine (SVM) method to determine whether GFC abnormalities could be utilized to distinguish the patients from the controls. Results. Relative to healthy controls, patients with BSP showed significantly decreased GFC in the bilateral superior medial prefrontal cortex/anterior cingulate cortex (MPFC/ACC) and increased GFC in the right postcentral gyrus/precentral gyrus/paracentral lobule, right superior frontal gyrus (SFG), and left paracentral lobule/supplement motor area (SMA), which were included in the default mode network (DMN) and sensorimotor network. SVM analysis showed that increased GFC values in the right postcentral gyrus/precentral gyrus/paracentral lobule could discriminate patients from controls with optimal accuracy, specificity, and sensitivity of 83.33%, 83.33%, and 83.33%, respectively. Conclusion. This study suggested that abnormal GFC in the brain areas associated with sensorimotor network and DMN might underlie the pathophysiology of BSP, which provided a new perspective to understand BSP. GFC in the right postcentral gyrus/precentral gyrus/paracentral lobule might be utilized as a latent biomarker to differentiate patients with BSP from controls.

scholarly journals The appropriacy of fluency tests in assessing epileptic seizure lateralization in children with partial epilepsy

Psihologija ◽  
2008 ◽  
Vol 41 (2) ◽  
pp. 195-211
Author(s):  
Jasmina Vuksanovic ◽  
Milena Djuric
Keyword(s):  
Left Hemisphere ◽  
Right Hemisphere ◽  
Partial Epilepsy ◽  
Quantitative Comparison ◽  
Control Group ◽  
Healthy Children ◽  
Healthy Controls ◽  
Seizure Focus ◽  
Qualitative And Quantitative ◽  
The Right

Fluency tests are frequently used in clinical practice to asses executive functions. The literature data are not unequivocal although in a great number of papers is pointed out the importance of the left hemisphere, specially of the left frontal lobes in the mediation of phonological fluency and the right hemisphere in the mediation of nonverbal fluency. This paper considers the suitability of fluency tests for the detection of left versus right seizure laterality. The sample consisted of thirty-two epilepsy patients divided into two groups: LHF-participants with the seizure focus in the left hemisphere (n=16), and DHF-participants with the seizure focus in the right hemisphere (n=16), and K-the control group of t age-matched healthy children (n=50) aged 7-11 years. The qualitative and quantitative comparison of the phonological and nonverbal fluency performance was carried out in consideration of the seizure laterality as well as compared to the healthy controls. The results of phonological fluency performance revealed that the performance of the LHF group was significantly reduced as compared to both DHF and K group. The analysis of nonverbal fluency performance revealed that the performance of the DHF group was significantly reduced as compared to both LHF and K group The qualitative analysis obtained valuable data, which could additionally contribute to the neuropsychological evaluation of the left versus right seizure laterality.

scholarly journals Hypoconnectivity networks in schizophrenia patients: a voxelwise meta-analysis of rs-fMRI

2021 ◽  
Author(s):  
Silvia Ruiz-Torras ◽  
Oscar Fernández-Vazquez ◽  
Cristina Cañete-Massé ◽  
Maribel Peró-Cebollero ◽  
Joan Guàrdia-Olmos
Keyword(s):  
Brain Connectivity ◽  
Meta Analysis ◽  
Superior Temporal Gyrus ◽  
Interesting Case ◽  
Control Group ◽  
Precentral Gyrus ◽  
Healthy Controls ◽  
Health States ◽  
The Right ◽  
Work Done

Abstract In the last few years, the field of brain connectivity has focused on identifying biomarkers to describe different health states and to discriminate between patients and healthy controls through the characterization of brain networks. A particularly interesting case, because of the symptoms' severity, is the work done with samples of patients diagnosed with schizophrenia. This meta-analysis aims to identify connectivity networks with different activation patterns between people diagnosed with schizophrenia and healthy controls. Therefore, we collected primary studies exploring whole brain connectivity by functional magnetic resonance imaging at rest in patients with schizophrenia compared to healthy people. Thus, we identified 25 high-quality studies that included a total of 1285 people with schizophrenia and 1279 healthy controls. The results indicate hypoactivation in the right precentral gyrus and in the left superior temporal gyrus of people with schizophrenia compared with the control group. These regions have been linked to deficits in gesticulation and the experience of auditory hallucinations in people with schizophrenia. A study of heterogeneity demonstrated that the effect size was influenced by the sample size and type of analysis. These results imply new contributions to the knowledge, diagnosis, and treatment of schizophrenia both clinically and in research.

scholarly journals Altered Intra- and Interregional Synchronization in Resting-State Cerebral Networks Associated with Chronic Tinnitus

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Yu-Chen Chen ◽  
Jian Zhang ◽  
Xiao-Wei Li ◽  
Wenqing Xia ◽  
Xu Feng ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Resting State ◽  
Brain Activity ◽  
Inferior Frontal Gyrus ◽  
Resting State Fmri ◽  
Brain Regions ◽  
Chronic Tinnitus ◽  
Healthy Controls ◽  
Tinnitus Distress ◽  
The Right

Objective. Subjective tinnitus is hypothesized to arise from aberrant neural activity; however, its neural bases are poorly understood. To identify aberrant neural networks involved in chronic tinnitus, we compared the resting-state functional magnetic resonance imaging (fMRI) patterns of tinnitus patients and healthy controls.Materials and Methods. Resting-state fMRI measurements were obtained from a group of chronic tinnitus patients (n=29) with normal hearing and well-matched healthy controls (n=30). Regional homogeneity (ReHo) analysis and functional connectivity analysis were used to identify abnormal brain activity; these abnormalities were compared to tinnitus distress.Results. Relative to healthy controls, tinnitus patients had significant greater ReHo values in several brain regions including the bilateral anterior insula (AI), left inferior frontal gyrus, and right supramarginal gyrus. Furthermore, the left AI showed enhanced functional connectivity with the left middle frontal gyrus (MFG), while the right AI had enhanced functional connectivity with the right MFG; these measures were positively correlated with Tinnitus Handicap Questionnaires (r=0.459,P=0.012andr=0.479,P=0.009, resp.).Conclusions. Chronic tinnitus patients showed abnormal intra- and interregional synchronization in several resting-state cerebral networks; these abnormalities were correlated with clinical tinnitus distress. These results suggest that tinnitus distress is exacerbated by attention networks that focus on internally generated phantom sounds.

scholarly journals Intact corticostriatal and altered subcortical circuits in chronic pain

2021 ◽  
Author(s):  
Su Hyoun Park ◽  
Anne K. Baker ◽  
Vinit Krishna ◽  
Katherine T. Martucci
Keyword(s):  
Chronic Pain ◽  
Functional Connectivity ◽  
Resting State ◽  
Chronic Back Pain ◽  
Healthy Controls ◽  
Significant Group ◽  
Total Mood Disturbance ◽  
Subcortical Regions ◽  
The Right ◽  
Clinical Measures

Previous research has demonstrated the importance of the corticostriatal circuit in chronic pain. By focusing on nucleus accumbens (NAcc) circuits related to reward, we aimed to clarify how altered brain reward systems contribute to chronic pain. Using resting-state functional magnetic resonance imaging, we compared NAcc-medial prefrontal cortex (MPFC) functional connectivity in patients with fibromyalgia vs. healthy controls. Among patients, we analyzed the extent to which functional connectivity correlated with clinical measures. We also examined NAcc functional connectivity to subcortical regions. Lastly, we compared our results to a separate dataset of patients with chronic back pain. We identified robust NAcc-MPFC functional connectivity among patients with fibromyalgia and healthy controls, with no significant group differences. We found a positive correlational trend between NAcc-MPFC functional connectivity and total mood disturbance. Notably, patients with fibromyalgia showed significantly reduced functional connectivity of the right NAcc with mesolimbic circuit regions compared to controls. These results were largely similar to the results from the separate dataset. Our results provide novel evidence of intact corticostriatal but altered subcortical functional connectivity of the NAcc during resting-state in chronic pain and suggest that measured connectivity may relate to changes in mood and the level of cognitive demand during fMRI-based measurement.

scholarly journals The Effect of Light Sedation with Midazolam on Functional Connectivity of the Dorsal Attention Network

2021 ◽  
Vol 11 (8) ◽  
pp. 1107
Author(s):  
Junkai Wang ◽  
Yachao Xu ◽  
Gopikrishna Deshpande ◽  
Kuncheng Li ◽  
Pei Sun ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Resting State ◽  
Drug Induced ◽  
Temporal Area ◽  
Attention Network ◽  
Sensorimotor Network ◽  
Dorsal Attention Network ◽  
Functional Patterns ◽  
Light Sedation ◽  
The Right

Altered connectivity within and between the resting-state networks (RSNs) brought about by anesthetics that induce altered consciousness remains incompletely understood. It is known that the dorsal attention network (DAN) and its anticorrelations with other RSNs have been implicated in consciousness. However, the role of DAN-related functional patterns in drug-induced sedative effects is less clear. In the current study, we investigated altered functional connectivity of the DAN during midazolam-induced light sedation. In a placebo-controlled and within-subjects experimental study, fourteen healthy volunteers received midazolam or saline with a 1-week interval. Resting-state fMRI data were acquired before and after intravenous drug administration. A multiple region of interest-driven analysis was employed to investigate connectivity within and between RSNs. It was found that functional connectivity was significantly decreased by midazolam injection in two regions located in the left inferior parietal lobule and the left middle temporal area within the DAN as compared with the saline condition. We also identified three clusters in anticorrelation between the DAN and other RSNs for the interaction effect, which included the left medial prefrontal cortex, the right superior temporal gyrus, and the right superior frontal gyrus. Connectivity between all regions and DAN was significantly decreased by midazolam injection. The sensorimotor network was minimally affected. Midazolam decreased functional connectivity of the dorsal attention network. These findings advance the understanding of the neural mechanism of sedation, and such functional patterns might have clinical implications in other medical conditions related to patients with cognitive impairment.

scholarly journals Resting State Functional MRI in Neonates with Prenatal Opioid Exposure: Analysis of Thalamocortical Functional Connectivity

2020 ◽  
Vol 3 ◽  
Author(s):  
Zoe Guckien ◽  
Jonathan Dietrich ◽  
Ramana Vishnubhotla ◽  
MaKayla Picklesimer ◽  
Christina Sparks ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Resting State ◽  
Public Health Issue ◽  
Control Group ◽  
Seed Region ◽  
Subcortical Structures ◽  
Neural Basis ◽  
Neurodevelopmental Outcomes ◽  
Caudate Nuclei ◽  
The Right

Background/Objective: Prenatal opioid exposure (POE) is a growing public health issue that can result in premature birth, Neonatal Abstinence Syndrome (NAS), and adverse neurodevelopmental outcomes. However, the neural basis for these findings remains relatively unknown. In this study, we aimed to investigate the neural correlates of POE based on neonatal thalamocortical functional connectivity using resting state functional magnetic resonance imaging (rs-fMRI).     Methods: In this prospective, IRB-approved study, nineteen neonates with POE and twenty opioid naive (ON) controls underwent non-invasive MRI during natural sleep at mean post-menstrual age (PMA) of 44.7 ± 2.6 and 44.6 ± 2.6 weeks respectively. MR imaging included anatomic T2-weighted images and rs-fMRI. General Linear Model (GLM) seed-based whole brain functional connectivity analysis was performed for each subject, with the right and left thalamus as distinct seed regions. Unpaired mixed-effects group analyses between POE and ON groups were conducted for each seed region corrected for PMA and sex.    Results: Thalamic connectivity to cortical and subcortical structures differed in the POE group compared to the ON control group. The POE group exhibited higher functional connectivity to deep gray structures, frontal, medial prefrontal, parietal, occipital, and anterior temporal cortices compared to controls. The POE group exhibited lower connectivity to the nuclei accumbentes, bilateral caudate nuclei, posterior cingulate gyri, superior frontal gyri, insular, and dorsolateral prefrontal cortices.     Conclusion and Potential Impact: Overall, these novel results suggest the presence of opioid exposure-related alterations in thalamic functional connectivity. Given that the thalamus plays a crucial role in early brain development, the described alterations in thalamocortical and thalamic-subcortical connectivity may have implications in stratifying risk and informing treatment for the adverse neurodevelopmental outcomes associated with POE. Future studies should explore the relationship between POE-associated disruptions in thalamic connectivity and developmental outcomes. 

White-matter markers for psychosis in a prospective ultra-high-risk cohort

2009 ◽  
Vol 40 (8) ◽  
pp. 1297-1304 ◽  
Author(s):  
O. J. N. Bloemen ◽  
M. B. de Koning ◽  
N. Schmitz ◽  
D. H. Nieman ◽  
H. E. Becker ◽  
...  
Keyword(s):  
White Matter ◽  
High Risk ◽  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Healthy Controls ◽  
Syndrome Scale ◽  
Ultra High Risk ◽  
Mri Scans ◽  
Magnetic Resonance Imaging Mri ◽  
The Right

BackgroundSubjects at ‘ultra high risk’ (UHR) for developing psychosis have differences in white matter (WM) compared with healthy controls. WM integrity has not yet been investigated in UHR subjects in relation to the development of subsequent psychosis. Hence, we investigated a prospective cohort of UHR subjects comparing whole brain fractional anisotropy (FA) of those later developing psychosis (UHR-P) to those who did not (UHR-NP).MethodWe recruited 37 subjects fulfilling UHR criteria and 10 healthy controls. Baseline 3 Tesla magnetic resonance imaging (MRI) scans and Positive and Negative Syndrome Scale (PANSS) ratings were obtained. UHR subjects were assessed at 9, 18 and 24 months for development of frank psychosis. We compared baseline FA of UHR-P to controls and UHR-NP subjects. Furthermore, we related clinical data to MRI outcome in the patient population.ResultsOf the 37 UHR subjects, 10 had transition to psychosis. UHR-P subjects showed significantly lower FA values than control subjects in medial frontal lobes bilaterally. UHR-P subjects had lower FA values than UHR-NP subjects, lateral to the right putamen and in the left superior temporal lobe. UHR-P subjects showed higher FA values, compared with UHR-NP, in the left medial temporal lobe. In UHR-P, positive PANSS negatively correlated to FA in the left middle temporal lobe. In the total UHR group positive PANSS negatively correlated to FA in the right superior temporal lobe.ConclusionsUHR subjects who later develop psychosis have differences in WM integrity, compared with UHR subjects who do not develop psychosis and to healthy controls, in brain areas associated with schizophrenia.

scholarly journals Mind-Body Exercise Modulates Locus Coeruleus and Ventral Tegmental Area Functional Connectivity in Individuals With Mild Cognitive Impairment

2021 ◽  
Vol 13 ◽  
Author(s):  
Jiao Liu ◽  
Jing Tao ◽  
Rui Xia ◽  
Moyi Li ◽  
Maomao Huang ◽  
...  
Keyword(s):  
Cognitive Impairment ◽  
Mild Cognitive Impairment ◽  
Functional Connectivity ◽  
Locus Coeruleus ◽  
Ventral Tegmental Area ◽  
Control Group ◽  
Brisk Walking ◽  
Area Functional ◽  
Ventral Tegmental ◽  
The Right

Mild cognitive impairment (MCI) is a common global health problem. Recently, the potential of mind-body intervention for MCI has drawn the interest of investigators. This study aims to comparatively explore the modulation effect of Baduanjin, a popular mind-body exercise, and physical exercise on the cognitive function, as well as the norepinephrine and dopamine systems using the resting state functional connectivity (rsFC) method in patients with MCI. 69 patients were randomized to the Baduanjin, brisk walking, or healthy education control group for 6 months. The Montreal Cognitive Assessment (MoCA) and magnetic resonance imaging (MRI) scans were applied at baseline and at the end of the experiment. Results showed that (1) compared to the brisk walking, the Baduanjin significantly increased MoCA scores; (2) Baduanjin significantly increased the right locus coeruleus (LC) and left ventral tegmental area (VTA) rsFC with the right insula and right amygdala compared to that of the control group; and the right anterior cingulate cortex (ACC) compared to that of the brisk walking group; (3) the increased right LC-right insula rsFC and right LC-right ACC rsFC were significantly associated with the corresponding MoCA score after 6-months of intervention; (4) both exercise groups experienced an increased effective connectivity from the right ACC to the left VTA compared to the control group; and (5) Baduanjin group experienced an increase in gray matter volume in the right ACC compared to the control group. Our results suggest that Baduanjin can significantly modulate intrinsic functional connectivity and the influence of the norepinephrine (LC) and dopamine (VTA) systems. These findings may shed light on the mechanisms of mind-body intervention and aid the development of new treatments for MCI.

Altered resting-state cerebellar-cerebral functional connectivity in obsessive-compulsive disorder

2018 ◽  
Vol 49 (07) ◽  
pp. 1156-1165 ◽  
Author(s):  
Tingting Xu ◽  
Qing Zhao ◽  
Pei Wang ◽  
Qing Fan ◽  
Jue Chen ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Obsessive Compulsive Disorder ◽  
Executive Control ◽  
Clinical Symptoms ◽  
Emotion Processing ◽  
Affective Processing ◽  
Obsessive Compulsive ◽  
Compulsive Disorder ◽  
Magnetic Resonance Imaging Mri ◽  
The Right

AbstractBackgroundThe role of the cerebellum in obsessive-compulsive disorder (OCD) has drawn increasing attention. However, the functional connectivity between the cerebellum and the cerebral cortex has not been investigated in OCD, nor has the relationship between such functional connectivity and clinical symptoms.MethodsA total of 27 patients with OCD and 21 healthy controls (HCs) matched on age, sex and education underwent magnetic resonance imaging (MRI). Seed-based connectivity analyses were performed to examine differences in cerebellar-cerebral connectivity in patients with OCD compared with HCs. Associations between functional connectivity and clinical features in OCD were analyzed.ResultsCompared with HCs, OCD patients showed significantly decreased cerebellar-cerebral functional connectivity in executive control and emotion processing networks. Within the OCD group, decreased functional connectivity in an executive network spanning the right cerebellar Crus I and the inferior parietal lobule was positively correlated with symptom severity, and decreased connectivity in an emotion processing network spanning the left cerebellar lobule VI and the lingual gyrus was negatively correlated with illness duration.ConclusionsAltered functional connectivity between the cerebellum and cerebral networks involved in cognitive-affective processing in patients with OCD provides further evidence for the involvement of the cerebellum in the pathophysiology of OCD, and is consistent with impairment in executive control and emotion regulation in this condition.

Sign in / Sign up

Export Citation Format

Share Document