New resting-state fMRI related studies at PubMed

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Neural Correlates of Body Integrity Dysphoria.

Mon, 05/11/2020 - 14:20

Neural Correlates of Body Integrity Dysphoria.

Curr Biol. 2020 May 01;:

Authors: Saetta G, Hänggi J, Gandola M, Zapparoli L, Salvato G, Berlingeri M, Sberna M, Paulesu E, Bottini G, Brugger P

Abstract
There are few things as irrefutable as the evidence that our limbs belong to us. However, persons with body integrity dysphoria (BID) [1] deny the ownership of one of their fully functional limbs and seek its amputation [2]. We tapped into the brain mechanisms of BID, examining sixteen men desiring the removal of the left healthy leg. The primary sensorimotor area of the to-be-removed leg and the core area of the conscious representation of body size and shape (the right superior parietal lobule [rSPL]) [3, 4] were less functionally connected to the rest of the brain. Furthermore, the left premotor cortex, reportedly involved in the multisensory integration of limb information [5-7], and the rSPL were atrophic. The more atrophic the rSPL, the stronger the desire for amputation, and the more an individual pretended to be an amputee by using wheelchairs or crutches to solve the mismatch between the desired and actual body. Our findings illustrate the pivotal role of the connectivity of the primary sensorimotor limb area in the mediation of the feeling of body ownership. They also delineate the morphometric and functional alterations in areas of higher-order body representation possibly responsible for the dissatisfaction with a standard body configuration. The neural correlates of BID may foster the understanding of other neuropsychiatric disorders involving the bodily self. Ultimately, they may help us understand what most of us take for granted, i.e., the experience of body and self as a seamless unity.

PMID: 32386532 [PubMed - as supplied by publisher]

A Sleeping rs-fMRI Study of Preschool Children with Autism Spectrum Disorders.

Mon, 05/11/2020 - 14:20

A Sleeping rs-fMRI Study of Preschool Children with Autism Spectrum Disorders.

Curr Med Imaging. 2020 May 09;:

Authors: Li X, Wang L, Qin B, Zhang Y, Zhou Z, Qin Y, Bao G, Huang J, Cai J

Abstract
OBJECTIVES: The brain functional network of autism spectrum disorders (ASDs) in the earlier stages of life has been almost unknown due to difficulties in obtaining a resting-state functional magnetic resonance imaging (rs-fMRI). This study aimed to perform rs-MRI under a sedated sleep state and reveal possible alterations in the brain functional network.
METHODS: Rs-fMRI was performed in a group of preschool children (aged 2-6 years, 53 with ASD, 63 as controls) under a sedated sleeping state. Based on graph theoretical analysis, global and local topological metrics were calculated to investigate alterations in brain functional networks. In addition, correlation analyses were conducted between the abnormal attribute values and Childhood Autism Rating Scale (CARS) scores.
RESULTS: The graph theoretical analysis showed that the nodal degree of the right medial frontal gyrus and the nodal efficiency of the right lingual gyrus in the ASD group were higher than those in the control group (P<0.05). There was a statistically significant positive correlation (R=0.318, P<0.05) between the right midfrontal gyrus nodal degree values and CARS scores in the ASD patients.
CONCLUSION: Alterations of some nodal attributes in the brain network has occurred in preschool autistic children and could serve as potential imaging biomarkers for evaluating ASD in earlier stages.

PMID: 32386497 [PubMed - as supplied by publisher]

Dissociable behavioral and neural correlates for target-changing and conforming behaviors in interpersonal aggression.

Sun, 05/10/2020 - 00:20

Dissociable behavioral and neural correlates for target-changing and conforming behaviors in interpersonal aggression.

eNeuro. 2020 May 07;:

Authors: Takami K, Haruno M

Abstract
Actors in interpersonal aggression such as bullies change their targets frequently, but the underlying behavioral and neural mechanisms are unknown. Here, using the catch-ball task we recently developed to examine human interpersonal aggression, we found target-changing and conforming to other participants' aggression are major driving forces of increased aggression (i.e., throwing strong balls). We also found that target-changing was correlated with a participant's extraversion, consistent with a bistrategic view, in which both prosocial and coercive motivations drive interpersonal aggression. In contrast, conforming to others was correlated with social anxiety. In addition, questionnaires about participants' past experiences of bullying suggested that target-changers and conformers were predominantly bullies and victims in the past. An analysis of resting-state fMRI revealed that functional connectivity between the dorsal anterior cingulate cortex and insula were correlated with target-changing behavior, while functional connectivity between the amygdala and temporo-parietal junction was correlated with conformity. These results demonstrate that target-changing and conforming behaviors have dissociable behavioral and neural mechanisms, and may contribute to real-world interpersonal aggressions differently.Significance Statement Our model-based integration of behaviors in a catch-ball task and resting-state fMRI data demonstrate that target-changing and conforming behaviors have dissociable behavioral and neural mechanisms, and contribute to real-world interpersonal aggressions differently.

PMID: 32381647 [PubMed - as supplied by publisher]

The influence of Parkinson's disease on the functional connectivity of the motor loop of human basal ganglia.

Sun, 05/10/2020 - 00:20
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The influence of Parkinson's disease on the functional connectivity of the motor loop of human basal ganglia.

Parkinsonism Relat Disord. 2019 06;63:100-105

Authors: Rodriguez-Sabate C, Morales I, Monton F, Rodriguez M

Abstract
Current basal ganglia models integrate information obtained from humans and animals to explain motor disorders in Parkinson's disease. These models explain some motor disturbances of Parkinson's disease (PD), but different clinical observations which remain unexplained have promoted the development of new basal ganglia (BG) models. The present study uses the time-relationship (partial correlation) of the BOLD-signal fluctuations to study the influence of PD on BG interactions of 17 age-matched controls (58.7 ± 5.3 years of age) and 24 PD patients (56.7 ± 8.4 years of age). Controls showed a complex functional connectivity of BG with a positive correlation between some nuclei (synchrony) and a negative correlation between other nuclei (anti-synchrony). This functional connectivity was different in PD-patients who showed: 1. an increased synchrony between the primary motor cortex(M1)-external pallidum(GPe), putamen(Put)-GPe, Put-subthalamic nucleus (STN), STN-internal pallidum (GPi), STN-motor thalamus (Tal), STN-GPi substantia nigra (SN) and SN-Tal, 2. a decreased synchrony between Put-GPi, GPe-STN, GPe-SN, STN-SN and GPi-SN, and 3. an increased anti-synchrony between GPe-SN and GPi-Tal. In control subjects, the motor-task increased the Put-Tal, GPi-SN and STN-Tal synchrony, decreased the STN-GPi and STN-SN synchrony and decreased the M1-GPe and the GPe-GPi anti-synchrony. The effect of the motor-task was very different in PD-patients, in whom it induced a decrease of the M1-GPe, STN-GPi and SN-Tal synchrony and a decrease of the GPe-Tal and GPe-SN anti-synchrony. Functional connectivity imaging methods may provide data that cannot be obtained by other methods in humans, and that may help to understand the physiology of BG and its deterioration in PD.

PMID: 30833228 [PubMed - indexed for MEDLINE]

Multimodality neuroimaging brain-age in UK biobank: relationship to biomedical, lifestyle, and cognitive factors.

Fri, 05/08/2020 - 10:20

Multimodality neuroimaging brain-age in UK biobank: relationship to biomedical, lifestyle, and cognitive factors.

Neurobiol Aging. 2020 Apr 08;92:34-42

Authors: Cole JH

Abstract
The brain-age paradigm is proving increasingly useful for exploring aging-related disease and can predict important future health outcomes. Most brain-age research uses structural neuroimaging to index brain volume. However, aging affects multiple aspects of brain structure and function, which can be examined using multimodality neuroimaging. Using UK Biobank, brain-age was modeled in n = 2205 healthy people with T1-weighted MRI, T2-FLAIR, T2∗, diffusion-MRI, task fMRI, and resting-state fMRI. In a held-out healthy validation set (n = 520), chronological age was accurately predicted (r = 0.78, mean absolute error = 3.55 years) using LASSO regression, higher than using any modality separately. Thirty-four neuroimaging phenotypes were deemed informative by the regression (after bootstrapping); predominantly gray-matter volume and white-matter microstructure measures. When applied to new individuals from UK Biobank (n = 14,701), significant associations with multimodality brain-predicted age difference (brain-PAD) were found for stroke history, diabetes diagnosis, smoking, alcohol intake and some, but not all, cognitive measures (corrected p < 0.05). Multimodality neuroimaging can improve brain-age prediction, and derived brain-PAD values are sensitive to biomedical and lifestyle factors that negatively impact brain and cognitive health.

PMID: 32380363 [PubMed - as supplied by publisher]

Functional Network Connectivity (FNC)-based Generative Adversarial Network (GAN) and Its Applications in Classification of Mental Disorders.

Fri, 05/08/2020 - 10:20

Functional Network Connectivity (FNC)-based Generative Adversarial Network (GAN) and Its Applications in Classification of Mental Disorders.

J Neurosci Methods. 2020 May 04;:108756

Authors: Zhao J, Huang J, Zhi D, Yan W, Ma X, Yang X, Li X, Ke Q, Jiang T, Calhoun VD, Sui J

Abstract
As a popular deep learning method, generative adversarial networks (GAN) have achieved outstanding performance in multiple classifications and segmentation tasks. However, the application of GANs to fMRI data is relatively rare. In this work, we proposed a functional network connectivity (FNC) based GAN for classifying psychotic disorders from healthy controls (HCs), in which FNC matrices were calculated by correlation of time courses derived from non-artefactual fMRI independent components (ICs). The proposed GAN model consisted of one discriminator (real FNCs) and one generator (fake FNCs), each has four fully-connected layers. The generator was trained to match the discriminator in the intermediate layers while simultaneously a new objective loss was determined for the generator to improve the whole classification performance. In a case for classifying 269 major depressive disorder (MDD) patients from 286 HCs, an average accuracy of 70.1% was achieved in 10-fold cross-validation, with at least 6% higher compared to the other 6 popular classification approaches (54.5-64.2%). In another application to discriminating 558 schizophrenia patients from 542 HCs from 7 sites, the proposed GAN model achieved 80.7% accuracy in leave-one-site-out prediction, outperforming support vector machine (SVM) and deep neural net (DNN) by 3%-6%. More importantly, we are able to identify the most contributing FNC nodes and edges with the strategy of leave-one-FNC-out recursively. To the best of our knowledge, this is the first attempt to apply the GAN model on the fMRI-based classification of mental disorders. Such a framework promises wide utility and great potential in neuroimaging biomarker identification.

PMID: 32380227 [PubMed - as supplied by publisher]

Altered functional connectivity of right inferior frontal gyrus subregions in bipolar disorder: a resting state fMRI study.

Fri, 05/08/2020 - 10:20

Altered functional connectivity of right inferior frontal gyrus subregions in bipolar disorder: a resting state fMRI study.

J Affect Disord. 2020 Apr 29;272:58-65

Authors: Zhang L, Li W, Wang L, Bai T, Ji GJ, Wang K, Tian Y

Abstract
The right inferior frontal gyrus (rIFG) is a key cortical node in the circuits of emotion and cognitive control, and it has been frequently associated with bipolar disorder (BP); however, a reliable pattern of aberrant rIFG activation and connectivity in bipolar disorder has yet to be established. To further elucidate rIFG abnormalities in different states of bipolar disorder, we examined activation and functional connectivity (FC) in five subregions of rIFG in bipolar disorder. A total of 83 participants, including those with bipolar depression (BPD; n = 25) and bipolar mania (BPM; n = 37) along with healthy control (HC) subjects (n = 26), were examined by resting state functional magnetic resonance imaging (rs-fMRI). Both BPD and BPM groups showed higher values of amplitude of low-frequency fluctuations (ALFF) than healthy control in four of the five rIFG subregions except cluster 2(posterior-ventral rIFG). Using five subregions of rIFG as seeds, the decreased FC in bipolar disorder was mainly between posterior-ventral rIFG(cluster 2) and multiple brain regions including the postcentral gyrus, the precentral gyrus, paracentral lobule, lingual Gyrus, fusiform and cerebellum posterior lobe. These results indicated that local activity and FC were altered within specific subregions of the rIFG in BP. These findings may provide the distinct functional connectivity of rIFG subregions in BP and suggest that the cluster2 (posterior-ventral rIFG) circuitry plays a crucial role in BP. Also, such abnormalities might help define a more precise intervention targets.

PMID: 32379621 [PubMed - as supplied by publisher]

Abnormal dynamic functional connectivity in Alzheimer's disease.

Fri, 05/08/2020 - 10:20
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Abnormal dynamic functional connectivity in Alzheimer's disease.

CNS Neurosci Ther. 2020 May 06;:

Authors: Gu Y, Lin Y, Huang L, Ma J, Zhang J, Xiao Y, Dai Z, Alzheimer's Disease Neuroimaging Initiative

Abstract
AIMS: Alzheimer's disease (AD) is a progressive neurodegenerative disorder. Previous studies have demonstrated abnormalities in functional connectivity (FC) of AD under the assumption that FC is stationary during scanning. However, studies on the FC dynamics of AD, which may provide more insightful perspectives in understanding the neural mechanisms of AD, remain largely unknown.
METHODS: Combining the sliding-window approach and the k-means algorithm, we identified three reoccurring dynamic FC states from resting-state fMRI data of 26 AD and 26 healthy controls. The between-group differences both in FC states and in regional temporal variability were calculated, followed by a correlation analysis of these differences with cognitive performances of AD patients.
RESULTS: We identified three reoccurring FC states and found abnormal FC mainly in the frontal and temporal cortices. The temporal properties of FC states were changed in AD as characterized by decreased dwell time in State I and increased dwell time in State II. Besides, we found decreased regional temporal variability mainly in the somatomotor, temporal and parietal regions. Disrupted dynamic FC was significantly correlated with cognitive performances of AD patients.
CONCLUSION: Our findings suggest abnormal dynamic FC in AD patients, which provides novel insights for understanding the pathophysiological mechanisms of AD.

PMID: 32378335 [PubMed - as supplied by publisher]

Structure-Function Connectomics Reveals Aberrant Developmental Trajectory Occurring at Preadolescence in the Autistic Brain.

Fri, 05/08/2020 - 10:20
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Structure-Function Connectomics Reveals Aberrant Developmental Trajectory Occurring at Preadolescence in the Autistic Brain.

Cereb Cortex. 2020 May 07;:

Authors: He C, Chen H, Uddin LQ, Erramuzpe A, Bonifazi P, Guo X, Xiao J, Chen H, Huang X, Li L, Sheng W, Liao W, Cortes JM, Duan X

Abstract
Accumulating neuroimaging evidence shows that age estimation obtained from brain connectomics reflects the level of brain maturation along with neural development. It is well known that autism spectrum disorder (ASD) alters neurodevelopmental trajectories of brain connectomics, but the precise relationship between chronological age (ChA) and brain connectome age (BCA) during development in ASD has not been addressed. This study uses neuroimaging data collected from 50 individuals with ASD and 47 age- and gender-matched typically developing controls (TDCs; age range: 5-18 years). Both functional and structural connectomics were assessed using resting-state functional magnetic resonance imaging and diffusion tensor imaging data from the Autism Brain Imaging Data Exchange repository. For each participant, BCA was estimated from structure-function connectomics through linear support vector regression. We found that BCA matched well with ChA in TDC children and adolescents, but not in ASD. In particular, our findings revealed that individuals with ASD exhibited accelerated brain maturation in youth, followed by a delay of brain development starting at preadolescence. Our results highlight the critical role of BCA in understanding aberrant developmental trajectories in ASD and provide the new insights into the pathophysiological mechanisms of this disorder.

PMID: 32377684 [PubMed - as supplied by publisher]

Different Degree Centrality Changes in the Brain after Acupuncture on Contralateral or Ipsilateral Acupoint in Patients with Chronic Shoulder Pain: A Resting-State fMRI Study.

Fri, 05/08/2020 - 10:20
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Different Degree Centrality Changes in the Brain after Acupuncture on Contralateral or Ipsilateral Acupoint in Patients with Chronic Shoulder Pain: A Resting-State fMRI Study.

Neural Plast. 2020;2020:5701042

Authors: Yan CQ, Huo JW, Wang X, Zhou P, Zhang YN, Li JL, Kim M, Shao JK, Hu SQ, Wang LQ, Liu CZ

Abstract
Chronic shoulder pain (CSP) is the third most common musculoskeletal problem. For maximum treatment effectiveness, most acupuncturists usually choose acupoint in the nonpainful side, to alleviate pain or improve shoulder function. This method is named opposite needling, which means acupuncture points on the right side are selected for diseases on the left side and vice versa. However, the underlying neural mechanisms related to treatment are currently unclear. The purpose of this study was to determine whether different mechanisms were observed with contralateral and ipsilateral acupuncture at Tiaokou (ST 38) in patients with unilateral CSP. Twenty-four patients were randomized to the contralateral acupuncture group (contra-group) and the ipsilateral acupuncture group (ipsi-group). The patients received one acupuncture treatment session at ST 38 on the nonpainful or painful sides, respectively. Before and after acupuncture treatment, they underwent functional magnetic resonance scanning. The treatment-related changes in degree centrality (DC) maps were compared between the two groups. We found alleviated pain and improved shoulder function in both groups, but better shoulder functional improvement was observed in the contra-group. Increased DC in the anterior/paracingulate cortex and decreased DC in bilateral postcentral gyri were found in the contra-group, while decreased DC in the bilateral cerebellum and right thalamus was observed in the ipsi-group. Furthermore, the DC value in the bilateral anterior/paracingulate cortex was positively correlated with the treatment-related change in the Constant-Murley score. The current study reveals different changes of DC patterns after acupuncture at contralateral or ipsilateral ST 38 in patients with CSP. Our findings support the hypothesis of acupoint specificity and provide the evidence for acupuncturists to select acupoints for CSP.

PMID: 32377180 [PubMed - in process]

Emerging functional connectivity differences in newborn infants vulnerable to autism spectrum disorders.

Fri, 05/08/2020 - 10:20
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Emerging functional connectivity differences in newborn infants vulnerable to autism spectrum disorders.

Transl Psychiatry. 2020 May 06;10(1):131

Authors: Ciarrusta J, Dimitrova R, Batalle D, O'Muircheartaigh J, Cordero-Grande L, Price A, Hughes E, Kangas J, Perry E, Javed A, Demilew J, Hajnal J, Edwards AD, Murphy D, Arichi T, McAlonan G

Abstract
Studies in animal models of autism spectrum disorders (ASD) suggest atypical early neural activity is a core vulnerability mechanism which alters functional connectivity and predisposes to dysmaturation of neural circuits. However, underlying biological changes associated to ASD in humans remain unclear. Results from functional connectivity studies of individuals diagnosed with ASD are highly heterogeneous, in part because of complex life-long secondary and/or compensatory events. To minimize these confounds and examine primary vulnerability mechanisms, we need to investigate very early brain development. Here, we tested the hypothesis that brain functional connectivity is altered in neonates who are vulnerable to this condition due to a family history of ASD. We acquired high temporal resolution multiband resting state functional magnetic resonance imaging (fMRI) in newborn infants with and without a first-degree relative with ASD. Differences in local functional connectivity were quantified using regional homogeneity (ReHo) analysis and long-range connectivity was assessed using distance correlation analysis. Neonates who have a first-degree relative with ASD had significantly higher ReHo within multiple resting state networks in comparison to age matched controls; there were no differences in long range connectivity. Atypical local functional activity may constitute a biomarker of vulnerability, that might precede disruptions in long range connectivity reported in older individuals diagnosed with ASD.

PMID: 32376820 [PubMed - in process]

Disrupted functional connectivity between sub-regions in the sensorimotor areas and cortex in migraine without aura.

Fri, 05/08/2020 - 10:20
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Disrupted functional connectivity between sub-regions in the sensorimotor areas and cortex in migraine without aura.

J Headache Pain. 2020 May 06;21(1):47

Authors: Qin Z, Su J, He XW, Ban S, Zhu Q, Cui Y, Zhang J, Hu Y, Liu YS, Zhao R, Qiao Y, Li J, Liu JR, Du X

Abstract
BACKGROUND: Migraine is a severe and disabling brain disorder, and the exact neurological mechanisms remain unclear. Migraineurs have altered pain perception, and headache attacks disrupt their sensory information processing and sensorimotor integration. The altered functional connectivity of sub-regions of sensorimotor brain areas with other brain cortex associated with migraine needs further investigation.
METHODS: Forty-eight migraineurs without aura during the interictal phase and 48 age- and sex-matched healthy controls underwent resting-state functional magnetic resonance imaging scans. We utilized seed-based functional connectivity analysis to investigate whether patients exhibited abnormal functional connectivity between sub-regions of sensorimotor brain areas and cortex regions.
RESULTS: We found that patients with migraineurs without aura exhibited disrupted functional connectivities between the sensorimotor areas and the visual cortex, temporal cortex, posterior parietal lobule, prefrontal areas, precuneus, cingulate gyrus, sensorimotor areas proper and cerebellum areas compared with healthy controls. In addition, the clinical data of the patients, such as disease duration, pain intensity and HIT-6 score, were negatively correlated with these impaired functional connectivities.
CONCLUSION: In patients with migraineurs without aura, the functional connectivities between the sensorimotor brain areas and other brain regions was reduced. These disrupted functional connectivities might contribute to abnormalities in visual processing, multisensory integration, nociception processing, spatial attention and intention and dysfunction in cognitive evaluation and modulation of pain. Recurrent headache attacks might lead to the disrupted network between primary motor cortex and temporal regions and between primary somatosensory cortex and temporal regions. Pain sensitivity and patient quality of life are closely tied to the abnormal functional connectivity between sensorimotor regions and other brain areas.

PMID: 32375638 [PubMed - in process]

Editorial: Pharmacological Effects on Striatal Resting-State Connectivity in Pediatric Obsessive-Compulsive Disorder: An Opportunity to Modulate Neurodevelopmental Trajectories?

Fri, 05/08/2020 - 10:20
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Editorial: Pharmacological Effects on Striatal Resting-State Connectivity in Pediatric Obsessive-Compulsive Disorder: An Opportunity to Modulate Neurodevelopmental Trajectories?

J Am Acad Child Adolesc Psychiatry. 2019 05;58(5):478-480

Authors: Via E

Abstract
The cortico-striato-thalamo-cortical (CSTC) circuit has been traditionally implicated in the underlying neural pathophysiology of obsessive-compulsive disorder (OCD). The CSTC involves parallel, partly segregated, but intrinsically communicating circuits involved in motor, cognitive, affective, and motivational processes.1,2.

PMID: 30799068 [PubMed - indexed for MEDLINE]

Concurrent Imaging of Markers of Current Flow and Neurophysiological Changes During tDCS.

Thu, 05/07/2020 - 16:00
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Concurrent Imaging of Markers of Current Flow and Neurophysiological Changes During tDCS.

Front Neurosci. 2020;14:374

Authors: Jog M, Jann K, Yan L, Huang Y, Parra L, Narr K, Bikson M, Wang DJJ

Abstract
Despite being a popular neuromodulation technique, clinical translation of transcranial direct current stimulation (tDCS) is hampered by variable responses observed within treatment cohorts. Addressing this challenge has been difficult due to the lack of an effective means of mapping the neuromodulatory electromagnetic fields together with the brain's response. In this study, we present a novel imaging technique that provides the capability of concurrently mapping markers of tDCS currents, as well as the brain's response to tDCS. A dual-echo echo-planar imaging (DE-EPI) sequence is used, wherein the phase of the acquired MRI-signal encodes the tDCS current induced magnetic field, while the magnitude encodes the blood oxygenation level dependent (BOLD) contrast. The proposed technique was first validated in a custom designed phantom. Subsequent test-retest experiments in human participants showed that tDCS-induced magnetic fields can be detected reliably in vivo. The concurrently acquired BOLD data revealed large-scale networks characteristic of a brain in resting-state as well as a 'cathodal' and an 'anodal' resting-state component under each electrode. Moreover, 'cathodal's BOLD-signal was observed to significantly decrease with the applied current at the group level in all datasets. With its ability to image markers of electromagnetic cause as well as neurophysiological changes, the proposed technique may provide an effective means to visualize neural engagement in tDCS at the group level. Our technique also contributes to addressing confounding factors in applying BOLD fMRI concurrently with tDCS.

PMID: 32372913 [PubMed]

Pushing the Limits of EEG: Estimation of Large-Scale Functional Brain Networks and Their Dynamics Validated by Simultaneous fMRI.

Thu, 05/07/2020 - 16:00
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Pushing the Limits of EEG: Estimation of Large-Scale Functional Brain Networks and Their Dynamics Validated by Simultaneous fMRI.

Front Neurosci. 2020;14:323

Authors: Abreu R, Simões M, Castelo-Branco M

Abstract
Functional magnetic resonance imaging (fMRI) is the technique of choice for detecting large-scale functional brain networks and to investigate their dynamics. Because fMRI measures brain activity indirectly, electroencephalography (EEG) has been recently considered a feasible tool for detecting such networks, particularly the resting-state networks (RSNs). However, a truly unbiased validation of such claims is still missing, which can only be accomplished by using simultaneously acquired EEG and fMRI data, due to the spontaneous nature of the activity underlying the RSNs. Additionally, EEG is still poorly explored for the purpose of mapping task-specific networks, and no studies so far have been focused on investigating networks' dynamic functional connectivity (dFC) with EEG. Here, we started by validating RSNs derived from the continuous reconstruction of EEG sources by directly comparing them with those derived from simultaneous fMRI data of 10 healthy participants, and obtaining an average overlap (quantified by the Dice coefficient) of 0.4. We also showed the ability of EEG to map the facial expressions processing network (FEPN), highlighting regions near the posterior superior temporal sulcus, where the FEPN is anchored. Then, we measured the dFC using EEG for the first time in this context, estimated dFC brain states using dictionary learning, and compared such states with those obtained from the fMRI. We found a statistically significant match between fMRI and EEG dFC states, and determined the existence of two matched dFC states which contribution over time was associated with the brain activity at the FEPN, showing that the dynamics of FEPN can be captured by both fMRI and EEG. Our results push the limits of EEG toward being used as a brain imaging tool, while supporting the growing literature on EEG correlates of (dynamic) functional connectivity measured with fMRI, and providing novel insights into the coupling mechanisms underlying the two imaging techniques.

PMID: 32372908 [PubMed]

Improved Resting-State Functional Dynamics in Post-stroke Depressive Patients After Shugan Jieyu Capsule Treatment.

Thu, 05/07/2020 - 16:00
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Improved Resting-State Functional Dynamics in Post-stroke Depressive Patients After Shugan Jieyu Capsule Treatment.

Front Neurosci. 2020;14:297

Authors: Yao G, Li J, Wang J, Liu S, Li X, Cao X, Chen H, Xu Y

Abstract
Shugan Jieyu Capsule (SG), a Chinese herbal medicine mainly composed of Acanthopanax and Hypericum perforatum, has been used to ameliorate cognitive impairments and emotional problems induced by post-stroke depression (PSD), while the altered brain dynamics underlying the ameliorative effects of SG have remained unclear. Our study focused on investigating the potential neurobiological mechanisms of SG in improving the cognitive function of PSD patients via resting-state functional magnetic resonance imaging (fMRI). Fifteen PSD patients (mean ages: 64.13 ± 6.01 years) were instructed to take 0.72 g of SG twice a day for 8 weeks. PSD patients underwent fMRIs, the 24-item Hamilton Depression Scale (HAMD-24) and the Montreal Cognitive Assessment (MoCA) at baseline and the end of intervention, and these assessments were also performed on twenty-one healthy controls (HC) (mean ages: 60.67 ± 6.95 years). Additionally, the dynamic amplitude of low-frequency fluctuations (dALFF) and functional connectivity (dFC) were determined to reveal changes in dynamic functional patterns. We found that taking SG significantly reduced the depressive symptoms assessed by HAMD-24 and improved cognitive functions assessed by MoCA in PSD patients. Furthermore, at baseline, PSD patients showed decreased dALFF in the right precuneus and increased dFC between the right precuneus and left angular gyrus, compared with HC. After intervention, the dALFF and dFC variances of the abnormal patterns were reversed. Additionally, the dALFF variance in the right precuneus was positively correlated with MoCA scores in PSD patients after SG treatment. Collectively, our results indicate that SG may improve the cognitive function of PSD patients through alteration of brain dynamics. Our findings lay a foundation for the exploration of the neurobiological mechanisms of SG in ameliorating symptoms of PSD patients.

PMID: 32372901 [PubMed]

Iterative consensus spectral clustering improves detection of subject and group level brain functional modules.

Thu, 05/07/2020 - 16:00
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Iterative consensus spectral clustering improves detection of subject and group level brain functional modules.

Sci Rep. 2020 May 05;10(1):7590

Authors: Gupta S, Rajapakse JC

Abstract
Specialized processing in the brain is performed by multiple groups of brain regions organized as functional modules. Although, in vivo studies of brain functional modules involve multiple functional Magnetic Resonance Imaging (fMRI) scans, the methods used to derive functional modules from functional networks of the brain ignore individual differences in the functional architecture and use incomplete functional connectivity information. To correct this, we propose an Iterative Consensus Spectral Clustering (ICSC) algorithm that detects the most representative modules from individual dense weighted connectivity matrices derived from multiple scans. The ICSC algorithm derives group-level modules from modules of multiple individuals by iteratively minimizing the consensus-cost between the two. We demonstrate that the ICSC algorithm can be used to derive biologically plausible group-level (for multiple subjects) and subject-level (for multiple subject scans) brain modules, using resting-state fMRI scans of 589 subjects from the Human Connectome Project. We employed a multipronged strategy to show the validity of the modularizations obtained from the ICSC algorithm. We show a heterogeneous variability in the modular structure across subjects where modules involved in visual and motor processing were highly stable across subjects. Conversely, we found a lower variability across scans of the same subject. The performance of our algorithm was compared with existing functional brain modularization methods and we show that our method detects group-level modules that are more representative of the modules of multiple individuals. Finally, the experiments on synthetic images quantitatively demonstrate that the ICSC algorithm detects group-level and subject-level modules accurately under varied conditions. Therefore, besides identifying functional modules for a population of subjects, the proposed method can be used for applications in personalized neuroscience. The ICSC implementation is available at https://github.com/SCSE-Biomedical-Computing-Group/ICSC.

PMID: 32371990 [PubMed - in process]

Altered spontaneous brain activity in patients with childhood absence epilepsy: associations with treatment effects.

Thu, 05/07/2020 - 16:00
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Altered spontaneous brain activity in patients with childhood absence epilepsy: associations with treatment effects.

Neuroreport. 2020 May 03;:

Authors: Yan Y, Xie G, Zhou H, Liu H, Wan M

Abstract
The study aims to detect resting-state functional MRI (RS-fMRI) changes and their relationships with the clinical treatment effects of anti-epileptic drugs (AEDs) for patients with childhood absence epilepsy (CAE) using the fractional amplitude of low-frequency fluctuation (fALFF). RS-fMRI data from 30 CAE patients were collected and compared with findings from 30 healthy controls (HCs) with matched sex and age. Patients were treated with first-line AEDs for 46.2 months before undergoing a second RS-fMRI scan. fALFF data were processed using DPABI and SPM12 software. Compared with the HCs, CAE patients at baseline showed increased fALFF in anterior cingulate cortex, inferior parietal lobule, inferior frontal lobule, supplementary motor area and reduced fALFF in putamen and thalamus. At follow-up, the fALFF showed a clear rebound which indicated a normalization of spontaneous brain activities in these regions. In addition, the fALFF changes within thalamus showed significant positive correlation with the seizure frequency improvements. Our results suggest that specific cortical and subcortical regions are involved in seizure generation and the neurological impairments found in CAE children and might shed new light about the AEDs effects on CAE patients.

PMID: 32371653 [PubMed - as supplied by publisher]

Orbitofrontal, dorsal striatum, and habenula functional connectivity in psychiatric patients with substance use problems.

Thu, 05/07/2020 - 16:00
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Orbitofrontal, dorsal striatum, and habenula functional connectivity in psychiatric patients with substance use problems.

Addict Behav. 2020 Apr 27;108:106457

Authors: Oh H, Lee J, Gosnell SN, Patriquin M, Kosten T, Salas R

Abstract
Substance abuse is commonly defined as the persistence of drug use despite negative consequences. Recent preclinical work has shown that higher input from the orbitofrontal cortex (OFC) to the dorsal striatum was associated with compulsive reward-seeking behavior despite negative effects. It remains unknown whether drug use is associated with the connectivity between the OFC and dorsal striatum in humans. We studied the resting state functional connectivity (RSFC) between the OFC, dorsal striatum, and habenula (and the whole brain in a separate analysis) in psychiatric inpatients with high (PU, problem users) and low (LU, low users) substance use. We matched PU and LU for psychiatric comorbidities. We found that PU showed higher RSFC between the left OFC and the left dorsal striatum than LU. RSFC between the habenula and both OFC and dorsal striatum was also higher in PU, which suggests the habenula may be a part of the same circuit. Finally, higher RSFC between the OFC and insula was also observed in PU. Our data shows that OFC, habenula, dorsal striatum, and insula may play an important role in PU. Furthermore, we postulate that the habenula may link the mesolimbic and cortico-striatal systems, which are altered in PU.

PMID: 32371303 [PubMed - as supplied by publisher]

Alterations in Local Connectivity and Their Developmental Trajectories in Autism Spectrum Disorder: Does Being Female Matter?

Wed, 05/06/2020 - 14:40
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Alterations in Local Connectivity and Their Developmental Trajectories in Autism Spectrum Disorder: Does Being Female Matter?

Cereb Cortex. 2020 May 05;:

Authors: Kozhemiako N, Nunes AS, Vakorin V, Iarocci G, Ribary U, Doesburg SM

Abstract
Autism spectrum disorder (ASD) is diagnosed more often in males with a ratio of 1:4 females/males. This bias is even stronger in neuroimaging studies. There is a growing evidence suggesting that local connectivity and its developmental trajectory is altered in ASD. Here, we aim to investigate how local connectivity and its age-related trajectories vary with ASD in both males and females. We used resting-state fMRI data from the ABIDE I and II repository: males (n = 102) and females (n = 92) with ASD, and typically developing males (n = 104) and females (n = 92) aged between 6 and 26. Local connectivity was quantified as regional homogeneity. We found increases in local connectivity in participants with ASD in the somatomotor and limbic networks and decreased local connectivity within the default mode network. These alterations were more pronounced in females with ASD. In addition, the association between local connectivity and ASD symptoms was more robust in females. Females with ASD had the most distinct developmental trajectories of local connectivity compared with other groups. Overall, our findings of more pronounced local connectivity alterations in females with ASD could indicate a greater etiological load for an ASD diagnosis in this group congruent with the female protective effect hypothesis.

PMID: 32368779 [PubMed - as supplied by publisher]

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