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The Instant Spontaneous Neuronal Activity Modulation of Transcutaneous Auricular Vagus Nerve Stimulation on Patients With Primary Insomnia.

Thu, 04/02/2020 - 21:43
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The Instant Spontaneous Neuronal Activity Modulation of Transcutaneous Auricular Vagus Nerve Stimulation on Patients With Primary Insomnia.

Front Neurosci. 2020;14:205

Authors: Zhao B, Bi Y, Li L, Zhang J, Hong Y, Zhang L, He J, Fang J, Rong P

Abstract
Primary insomnia (PI) is associated with increased spontaneous neuronal activity. Transcutaneous auricular vagus nerve stimulation (taVNS) modulates brain function, and it is an effective treatment for primary insomnia. However, whether taVNS alleviates insomnia through modulating spontaneous neuronal activity is not fully clarified. This study aims to investigate the instant effect of taVNS in modulating spontaneous neuronal activity in PI patients using resting-state functional magnetic resonance imaging (rs-fMRI). Twenty-two PI subjects underwent rs-fMRI scanning prior and immediately after 30 min treatment of taVNS controlled by twenty healthy adults. Amplitude of low frequency fluctuations (ALFF) analysis was employed to assess the difference in spontaneous neuronal activity between PI patients and healthy adults, as well as between pre-treatment and post-treatment of taVNS. The taVNS-induced altered ALFF brain areas were then selected as regions of interest to perform the resting state functional connectivity (RSFC) analysis in PI patients. The right precuneus showed significantly increased ALFF in PI patients. After immediate taVNS treatment, the ALFF was significantly decreased in the right precuneus and increased in the left middle occipital gyrus. The RSFC in right precuneus with right angular, right superior frontal gyrus, and right middle frontal gyrus was significantly decreased. This study provides insights into the instant brain effects of taVNS on PI patients.

PMID: 32231517 [PubMed]

A study on BOLD fMRI of the brain basic activities of MDD and the first-degree relatives.

Thu, 04/02/2020 - 21:43
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A study on BOLD fMRI of the brain basic activities of MDD and the first-degree relatives.

Int J Psychiatry Clin Pract. 2020 Mar 31;:1-9

Authors: Song Y, Shen X, Mu X, Mao N, Wang B

Abstract
Introduction: The present study aims to explore the characteristics and differences of the ReHo, ALFF and fALFF of brain in the resting state of depression and first-degree relatives, in order to identify candidate central prodromal biomarkers of depression.Method: Three groups of medication-free patients (39-59 years old) was involved in this study, including the patients with major depression disorder (MDD group, n = 15), healthy volunteers with first-degree relatives with MDD (first-degree relatives group, n = 15), healthy volunteers with no personal or family history of MDD (the control group [HC], n = 15). Participants underwent functional MRI while staying in a resting state after a conventional MRI scanning on a clinical 3 T system(Siemens Skyra, Germany).Results: The ReHo, ALFF and fALFF values are different in brain of MDD, first-degree relatives, and HC (p<.05). MDD patients exhibited abnormal spontaneous activity in multiple brain regions which are closely related to emotion regulation and perception. The present findings provide further insight into the pathological mechanisms underlying MDD.Conclusion: With the widespread abnormal values of brain in MDD and first-degree relatives measured, we can get a hypothesis that these abnormalities may be associated with cognitive network disorders and emotional distress in MDD.Key pointsThe fMRI could increase the early validity of MDD as a new diagnostic and disease-monitoring tool.Monitoring ReHo, ALFF, fALFF values using fMRI can provide insight into the presence and evolution of MDD disease and permit objective evaluation of brain abnormalities.It appears that ReHo, ALFF, fALFF could be used as markers for monitoring disease progression and treatment effects in MDD patients in the future.

PMID: 32228280 [PubMed - as supplied by publisher]

Magnetic resonance imaging biomarkers of brain connectivity in predicting outcome after mild traumatic brain injury: a systematic review.

Thu, 04/02/2020 - 21:43
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Magnetic resonance imaging biomarkers of brain connectivity in predicting outcome after mild traumatic brain injury: a systematic review.

J Neurotrauma. 2020 Mar 31;:

Authors: Puig J, Ellis M, Kornelsen J, Figley TD, Figley CR, Daunis-I-Estadella P, Mutch A, Essig M

Abstract
There is growing interest in developing magnetic resonance imaging (MRI) biomarkers of brain connectivity from resting-state functional (rs-fMRI) and diffusion tensor imaging (DTI) to aid in the management of patients with mild traumatic brain injury (mTBI). To determine whether early MRI biomarkers of brain connectivity are useful in predicting outcome after mTBI, we conducted a systematic review using the following inclusion criteria: (1) patients aged>16 years with mTBI, (2) MRI performed during the first month post-injury, (3) outcome measure available, (4) control group, and (5) original paper published in a peer-reviewed journal. Of the 1351 citations identified, 14 studies met inclusion criteria (5 rs-fMRI and 10 DTI; 680 mTBI patients vs 436 controls) including those where MRI was performed from <12 hours to 1 month post-injury. The most common clinical outcome measure used in these studies was symptom burden using the Rivermead Post-Concussion Questionnaire. The most frequently studied brain connectivity MRI biomarkers were global functional connectivity, default-mode network, and fractional anisotropy. Despite the scant evidence and considerable methodological heterogeneity observed among studies, we conclude that brain connectivity MRI biomarkers obtained within one month of injury may be potentially useful in predicting outcome in mTBI. Further longitudinal studies are needed to evaluate the effect of mTBI on MRI-based brain connectivity biomarkers and examine how incorporation of these tests can inform the clinical care of individual mTBI patients.

PMID: 32228145 [PubMed - as supplied by publisher]

Global fMRI signal at rest relates to symptom severity in schizophrenia.

Tue, 03/31/2020 - 21:42
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Global fMRI signal at rest relates to symptom severity in schizophrenia.

Schizophr Res. 2020 Mar 25;:

Authors: Umeh A, Kumar J, Francis ST, Liddle PF, Palaniyappan L

PMID: 32222349 [PubMed - as supplied by publisher]

Neural Basis of Smoking-Related Difficulties in Emotion Regulation.

Mon, 03/30/2020 - 21:40
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Neural Basis of Smoking-Related Difficulties in Emotion Regulation.

Int J Neuropsychopharmacol. 2020 Mar 27;:

Authors: Faulkner P, Dean AC, Ghahremani DG, London ED

Abstract
BACKGROUND: Negative emotional states contribute to cigarette smoking, and difficulties in regulating these states can hinder smoking cessation. Understanding the neural bases of these difficulties in smokers may facilitate development of novel therapies for Tobacco Use Disorder.
METHODS: Thirty-seven participants (18 smokers, 19 nonsmokers; 16-21 years old) completed the Difficulties in Emotion Regulation Scale (DERS), which is comprised of 6 subscales (lack of emotional clarity, lack of emotional awareness, limited access to emotion regulation strategies, nonacceptance of emotional responses, difficulties engaging in goal-directed behaviors, and impulse control difficulties) that combine to provide a total score. Participants also underwent functional magnetic resonance imaging to determine resting-state functional connectivity of the amygdala. Separate ANOVAs were used to determine group differences in self-reports on the DERS. Voxel-wise linear mixed models were performed to determine whether group influenced relationships between whole-brain functional connectivity of the amygdala and scores on the DERS.
RESULTS: Compared with nonsmokers, smokers reported greater difficulties in emotion regulation, denoted by higher total scores on the DERS. Group differences were observed on a subscale of lack of emotional clarity, but no other subscale differences on the DERS were observed. Nonsmokers exhibited a greater negative correlation than smokers between lack of emotional clarity scores and connectivity of the amygdala with the left inferior frontal gyrus. Finally, this amygdala-to-left inferior frontal gyrus connectivity was weaker in smokers than in nonsmokers.
CONCLUSIONS: These findings suggest that difficulties in emotion regulation in smokers are at least partially due to lack of emotional clarity. Given the role of the inferior frontal gyrus in understanding emotional states, strengthening connectivity between the amygdala and the inferior frontal gyrus may improve emotional clarity to help smokers regulate their negative emotions, thereby improving their ability to quit smoking.

PMID: 32221527 [PubMed - as supplied by publisher]

Electrical status epilepticus in sleep affects intrinsically connected networks in patients with benign childhood epilepsy with centrotemporal spikes.

Mon, 03/30/2020 - 21:40
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Electrical status epilepticus in sleep affects intrinsically connected networks in patients with benign childhood epilepsy with centrotemporal spikes.

Epilepsy Behav. 2020 Mar 25;106:107032

Authors: He W, Liu H, Liu Z, Wu Q

Abstract
BACKGROUND: Although outcomes of benign childhood epilepsy with centrotemporal spikes (BECTS) are frequently excellent, some atypical forms of BECTS, especially electrical status epilepticus in sleep (ESES), are characterized by worse outcomes and negative impacts on cognitive development.
METHODS: To explore specific ESES-related brain networks in patients with BECTS, we used resting-state functional magnetic resonance imaging (fMRI) to scan patients with BECTS with ESES (n = 9), patients with BECTS without ESES (n = 17), and healthy controls (n = 36). Unbiased seed-based whole-brain functional connectivity (FC) was adopted to explore the connectivity mode of three resting-state cerebral networks: the default mode network (DMN), salience network (SN), and central executive network (CEN).
RESULTS: Compared with the other two groups, patients with BECTS with ESES showed FC in the SN or in the CEN decreased, but not in the DMN. Moreover, we found the FC in the CEN in patients with BECTS without ESES decreased when compared with controls. Our currently intrinsically defined anticorrelated networks strength was disrupted in BECTS and connote greater deactivation than the results from FC for a seed region in children with BECTS.
CONCLUSION: These results indicated that children with BECTS with ESES showed brain activity altered in the CEN and the SN. The difference of impairment in the SN and CEN may lead to improve the understanding of the underlying neuropathophysiology, and to assess the activity of patients with BECTS with ESES, which is crucial for measuring disease activity, improving patient care, and assessing the effect of antiepilepsy therapy.

PMID: 32220803 [PubMed - as supplied by publisher]

Impaired connectivity within neuromodulatory networks in multiple sclerosis and clinical implications.

Sun, 03/29/2020 - 21:39
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Impaired connectivity within neuromodulatory networks in multiple sclerosis and clinical implications.

J Neurol. 2020 Mar 26;:

Authors: Carotenuto A, Wilson H, Giordano B, Caminiti SP, Chappell Z, Williams SCR, Hammers A, Silber E, Brex P, Politis M

Abstract
There is mounting evidence regarding the role of impairment in neuromodulatory networks for neurodegenerative diseases, such as Parkinson's and Alzheimer's disease. However, the role of neuromodulatory networks in multiple sclerosis (MS) has not been assessed. We applied resting-state functional connectivity and graph theory to investigate the changes in the functional connectivity within neuromodulatory networks including the serotonergic, noradrenergic, cholinergic, and dopaminergic systems in MS. Twenty-nine MS patients and twenty-four age- and gender-matched healthy controls performed clinical and cognitive assessments including the expanded disability status score, symbol digit modalities test, and Hamilton Depression rating scale. We demonstrated a diffuse reorganization of network topography (P < 0.01) in serotonergic, cholinergic, noradrenergic, and dopaminergic networks in patients with MS. Serotonergic, noradrenergic, and cholinergic network functional connectivity derangement was associated with disease duration, EDSS, and depressive symptoms (P < 0.01). Derangements in serotonergic, noradrenergic, cholinergic, and dopaminergic network impairment were associated with cognitive abilities (P < 0.01). Our results indicate that functional connectivity changes within neuromodulatory networks might be a useful tool in predicting disability burden over time, and could serve as a surrogate endpoint to assess efficacy for symptomatic treatments.

PMID: 32219555 [PubMed - as supplied by publisher]

Heterogeneity of executive function revealed by a functional random forest approach across ADHD and ASD.

Sun, 03/29/2020 - 21:39
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Heterogeneity of executive function revealed by a functional random forest approach across ADHD and ASD.

Neuroimage Clin. 2020 Mar 16;26:102245

Authors: Cordova M, Shada K, Demeter DV, Doyle O, Miranda-Dominguez O, Perrone A, Schifsky E, Graham A, Fombonne E, Langhorst B, Nigg J, Fair DA, Feczko E

Abstract
BACKGROUND: Those with autism spectrum disorder (ASD) and/or attention-deficit-hyperactivity disorder (ADHD) exhibit symptoms of hyperactivity and inattention, causing significant hardships for families and society. A potential mechanism involved in these conditions is atypical executive function (EF). Inconsistent findings highlight that EF features may be shared or distinct across ADHD and ASD. With ADHD and ASD each also being heterogeneous, we hypothesized that there may be nested subgroups across disorders with shared or unique underlying mechanisms.
METHODS: Participants (N = 130) included adolescents aged 7-16 with ASD (n = 64) and ADHD (n = 66). Typically developing (TD) participants (n = 28) were included for a comparative secondary sub-group analysis. Parents completed the K-SADS and youth completed an extended battery of executive and other cognitive measures. A two stage hybrid machine learning tool called functional random forest (FRF) was applied as a classification approach and then subsequently to subgroup identification. We input 43 EF variables to the classification step, a supervised random forest procedure in which the features estimated either hyperactive or inattentive ADHD symptoms per model. The FRF then produced proximity matrices and identified optimal subgroups via the infomap algorithm (a type of community detection derived from graph theory). Resting state functional connectivity MRI (rs-fMRI) was used to evaluate the neurobiological validity of the resulting subgroups.
RESULTS: Both hyperactive (Mean absolute error (MAE) = 0.72, Null model MAE = 0.8826, (t(58) = -4.9, p < .001) and inattentive (MAE = 0.7, Null model MAE = 0.85, t(58) = -4.4, p < .001) symptoms were predicted better than chance by the EF features selected. Subgroup identification was robust (Hyperactive: Q = 0.2356, p < .001; Inattentive: Q = 0.2350, p < .001). Two subgroups representing severe and mild symptomology were identified for each symptom domain. Neuroimaging data revealed that the subgroups and TD participants significantly differed within and between multiple functional brain networks, but no consistent "severity" patterns of over or under connectivity were observed between subgroups and TD.
CONCLUSION: The FRF estimated hyperactive/inattentive symptoms and identified 2 distinct subgroups per model, revealing distinct neurocognitive profiles of Severe and Mild EF performance per model. Differences in functional connectivity between subgroups did not appear to follow a severity pattern based on symptom expression, suggesting a more complex mechanistic interaction that cannot be attributed to symptom presentation alone.

PMID: 32217469 [PubMed - as supplied by publisher]

Salience-thalamic circuit uncouples in major depressive disorder, but not in bipolar depression.

Sun, 03/29/2020 - 21:39
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Salience-thalamic circuit uncouples in major depressive disorder, but not in bipolar depression.

J Affect Disord. 2020 Mar 03;269:43-50

Authors: Zeng C, Xue Z, Ross B, Zhang M, Liu Z, Wu G, Ouyang X, Li D, Pu W

Abstract
BACKGROUND: Bipolar depression (BDD) and major depressive disorder (MDD) are two diseases both characterized by depressed mood and diminished interest or pleasure. Recent neuroimaging studies have implicated the thalamo-cortical circuit in mood disorders, and the present study aimed to map thalamo-cortical connectivity to explore the dissociable and common abnormalities between bipolar and major depression in this circuit.
METHOD: Applying resting-state functional magnetic resonance imaging (fMRI), we mapped the thalamo-cortical circuit using a fine-grained thalamic atlas with 8 sub-regions bilaterally in 38 BDD patients, 42 MDD patients and 39 healthy controls (HCs). Correlation analysis was then performed between thalamo-cortical connectivity and clinical variables.
RESULT: The findings showed that both patient groups exhibited prefronto-thalamo-cerebellar and sensorimotor-thalamic hypoconnectivity, while the abnormalities in MDD were more extensive. Particularly, MDD group showed decreased thalamic connectivity with the salience network including the insula, anterior cingulate cortex (ACC), and striatum. No correlations were found between the abnormal thalamo-cortical connectivity and clinical symptoms in either patient group.
LIMITATION: Most patients in our study were taking drugs at the time of scanning, which may confound our findings.
CONCLUSION: Our finding suggest that the thalamo-cortical hypofunction is a common neuro-substrate for BDD and MDD. Specifically, the hypoconnectivity between the thalamus and salience network including the insula, ACC and striatum may be a distinguished biomarker for MDD, which may help to differentiate these two emotional disorders.

PMID: 32217342 [PubMed - as supplied by publisher]

Disturbed resting-state whole-brain functional connectivity of striatal subregions in bulimia nervosa.

Sat, 03/28/2020 - 21:37
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Disturbed resting-state whole-brain functional connectivity of striatal subregions in bulimia nervosa.

Int J Neuropsychopharmacol. 2020 Mar 26;:

Authors: Wang L, Bi K, Song Z, Zhang Z, Li K, Kong QM, Li XN, Lu Q, Si TM

Abstract
BACKGROUND: Disturbed self-regulation, taste reward, as well as somatosensory and visuospatial processes were thought to drive binge eating and purging behaviors that characterize bulimia nervosa (BN). Although studies have implicated a central role of the striatum in these dysfunctions, there have been no direct investigations on striatal functional connectivity (FC) in BN from a network perspective.
METHOD: We calculated the FC of striatal subregions based on the resting-state fMRI data of 51 BN patients and 53 healthy women.
RESULTS: Compared with the healthy women, BN patients showed increased positive FC in bilateral striatal nuclei and thalamus for nearly all of the striatal subregions, and increased negative FC in bilateral primary sensorimotor cortex and occipital areas for both ventral striatum and putamen subregions. Only for the putamen subregions, we observed reduced negative FC in the prefrontal (bilateral superior and middle frontal gyri) and parietal (right inferior parietal lobe and precuneus) areas. Several striatal connectivities with occipital and primary sensorimotor cortex significantly correlated with the severity of bulimia.
CONCLUSION: The findings indicate BN-related alterations in striatal FC with the dorsolateral prefrontal cortex supporting self-regulation, the subcortical striatum and thalamus involved in taste reward, as well as the visual occipital and sensorymotor regions mediating body image, which contribute to our understanding of neural circuitry of BN and encourage future therapeutic developments for BN by modulating striatal pathway.

PMID: 32215560 [PubMed - as supplied by publisher]

Differential Effects of Tai Chi Chuan (Motor-Cognitive Training) and Walking on Brain Networks: A Resting-State fMRI Study in Chinese Women Aged 60.

Sat, 03/28/2020 - 21:37
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Differential Effects of Tai Chi Chuan (Motor-Cognitive Training) and Walking on Brain Networks: A Resting-State fMRI Study in Chinese Women Aged 60.

Healthcare (Basel). 2020 Mar 24;8(1):

Authors: Yue C, Zhang Y, Jian M, Herold F, Yu Q, Mueller P, Lin J, Wang G, Tao Y, Zhang Z, Zou L

Abstract
Background: This cross-sectional study aimed to investigate whether a long-term engagement in different types of physical exercise may influence resting-state brain networks differentially. In particular, we studied if there were differences in resting-state functional connectivity measures when comparing older women who are long-term practitioners of tai chi chuan or walking. Method: We recruited 20 older women who regularly practiced tai chi chuan (TCC group), and 22 older women who walked regularly (walking group). Both the TCC group and the walking group underwent a resting-state functional magnetic resonance imaging (rs-fMRI) scan. The acquired rs-fMRI data of all participants were analyzed using independent component analysis. Age and years of education were added as co-variables. Results: There were significant differences in default network, sensory-motor network, and visual network of rs-fMRI between the TCC group and walking group (p < 0.05). Conclusions: The findings of the current study suggested that long-term practice of different types of physical exercises (TCC vs. walking) influenced brain functional networks and brain functional plasticity of elderly women differentially. Our findings encourage further research to investigate whether those differences in resting-state functional connectivity as a function of the type of physical exercise have implications for the prevention of neurological diseases.

PMID: 32213980 [PubMed]

Resting state networks activity in euthymic Bipolar Disorder.

Sat, 03/28/2020 - 03:37
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Resting state networks activity in euthymic Bipolar Disorder.

Bipolar Disord. 2020 Mar 25;:

Authors: Bellani M, Bontempi P, Zovetti N, Rossetti MG, Perlini C, Dusi N, Squarcina L, Marinelli V, Zoccatelli G, Alessandrini F, Ciceri EFM, Sbarbati A, Brambilla P

Abstract
OBJECTIVES: Bipolar disorder (BD) is a psychiatric condition causing shifts in mood, energy and activity levels severely altering the quality of life of the patients even in the euthymic phase. Although widely accepted, the neurobiological bases of the disorder in the euthymic phase remain elusive. This study aims at characterizing resting state functional activity of the BD euthymic phase in order to better understand the pathogenesis of the disease and build future neurobiological models.
METHODS: Fifteen euthymic BD patients (10 females; mean age 40.2; standard deviation 13.5; range 20-61) and 27 healthy controls (HC) (21 females; mean age 37; standard deviation 10.6; range 22-60) underwent a 3T functional MRI scan at rest. Resting state activity was extracted through independent component analysis (ICA) run with automatic dimensionality estimation.
RESULTS: ICA identified 22 resting state networks (RSNs). Within-network analysis revealed decreased connectivity in the visual, temporal, motor and cerebellar RSNs of BD patients versus HC. Between-network analysis showed increased connectivity between motor area and the default mode network (DMN) partially overlapping with the fronto-parietal network (FPN) in BD patients.
CONCLUSION: Within-network analysis confirmed existing evidence of altered cerebellar, temporal, motor and visual networks in BD. Increased connectivity between the DMN and the motor area network suggests the presence of alterations of the fronto-parietal regions, precuneus and cingulate cortex in the euthymic condition. These findings indicate that specific connectivity alterations might persist even in the euthymic state suggesting the importance of examining both within and between-network connectivity to achieve a global understanding of the BD euthymic condition.

PMID: 32212391 [PubMed - as supplied by publisher]

The Reorganization of Insular Subregions in Individuals with Below-Level Neuropathic Pain following Incomplete Spinal Cord Injury.

Sat, 03/28/2020 - 03:37
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The Reorganization of Insular Subregions in Individuals with Below-Level Neuropathic Pain following Incomplete Spinal Cord Injury.

Neural Plast. 2020;2020:2796571

Authors: Li X, Wang L, Chen Q, Hu Y, Du J, Chen X, Zheng W, Lu J, Chen N

Abstract
Objective: To investigate the reorganization of insular subregions in individuals suffering from neuropathic pain (NP) after incomplete spinal cord injury (ISCI) and further to disclose the underlying mechanism of NP.
Method: The 3D high-resolution T1-weighted structural images and resting-state functional magnetic resonance imaging (rs-fMRI) of all individuals were obtained using a 3.0 Tesla MRI system. A comparative analysis of structure and function connectivity (FC) with insular subareas as seeds in 10 ISCI individuals with below-level NP (ISCI-P), 11 ISCI individuals without NP (ISCI-N), and 25 healthy controls (HCs) was conducted. Associations between the structural and functional alteration of insula subregions and visual analog scale (VAS) scores were analyzed using the Pearson correlation in SPSS 20.
Results: Compared with ISCI-N patients, when the left posterior insula as the seed, ISCI-P showed increased FC in right cerebellum VIIb and cerebellum VIII, Brodmann 37 (BA 37). When the left ventral anterior insula as the seed, ISCI-P indicated enhanced FC in right BA18 compared with ISCI-N patients. These increased FCs positively correlated with VAS scores. Relative to HCs, ISCI-P presented increased FC in the left hippocampus when the left dorsal anterior insula was determined as the seed. There was no statistical difference in the volume of insula subregions among the three groups.
Conclusion: Our study indicated that distinctive patterns of FC in each subregion of insula suggest that the insular subareas participate in the NP processing through different FC following ISCI. Further, insula subregions could serve as a therapeutic target for NP following ISCI.

PMID: 32211038 [PubMed - in process]

Functional Brain Network Connectivity Patterns Associated With Normal Cognition at Old-Age, Local β-amyloid, Tau, and APOE4.

Sat, 03/28/2020 - 03:37
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Functional Brain Network Connectivity Patterns Associated With Normal Cognition at Old-Age, Local β-amyloid, Tau, and APOE4.

Front Aging Neurosci. 2020;12:46

Authors: Quevenco FC, van Bergen JM, Treyer V, Studer ST, Kagerer SM, Meyer R, Gietl AF, Kaufmann PA, Nitsch RM, Hock C, Unschuld PG

Abstract
Background: Integrity of functional brain networks is closely associated with maintained cognitive performance at old age. Consistently, both carrier status of Apolipoprotein E ε4 allele (APOE4), and age-related aggregation of Alzheimer's disease (AD) pathology result in altered brain network connectivity. The posterior cingulate and precuneus (PCP) is a node of particular interest due to its role in crucial memory processes. Moreover, the PCP is subject to the early aggregation of AD pathology. The current study aimed at characterizing brain network properties associated with unimpaired cognition in old aged adults. To determine the effects of age-related brain change and genetic risk for AD, pathological proteins β-amyloid and tau were measured by Positron-emission tomography (PET), PCP connectivity as a proxy of cognitive network integrity, and genetic risk by APOE4 carrier status. Methods: Fifty-seven cognitively unimpaired old-aged adults (MMSE = 29.20 ± 1.11; 73 ± 8.32 years) were administered 11C Pittsburgh Compound B and 18F Flutemetamol PET for assessing β-amyloid, and 18F AV-1451 PET for tau. Individual functional connectivity seed maps of the PCP were obtained by resting-state multiband BOLD functional MRI at 3-Tesla for increased temporal resolution. Voxelwise correlations between functional connectivity, β-amyloid- and tau-PET were explored by Biological Parametric Mapping (BPM). Results: Local β-amyloid was associated with increased connectivity in frontal and parietal regions of the brain. Tau was linked to increased connectivity in more spatially distributed clusters in frontal, parietal, occipital, temporal, and cerebellar regions. A positive interaction was observable for APOE4 carrier status and functional connectivity with brain regions characterized by increased local β-amyloid and tau tracer retention. Conclusions: Our data suggest an association between spatially differing connectivity systems and local β-amyloid, and tau aggregates in cognitively normal, old-aged adults, which is moderated by APOE4. Additional longitudinal studies may determine protective connectivity patterns associated with healthy aging trajectories of AD-pathology aggregation.

PMID: 32210782 [PubMed]

Altered Brain Function in Young HIV Patients with Syphilis Infection: A Voxel-Wise Degree Centrality Analysis.

Sat, 03/28/2020 - 03:37
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Altered Brain Function in Young HIV Patients with Syphilis Infection: A Voxel-Wise Degree Centrality Analysis.

Infect Drug Resist. 2020;13:823-833

Authors: Zhang XD, Liu GX, Wang XY, Huang XJ, Li JL, Li RL, Li HJ

Abstract
Objective: This study assessed the possible effect of syphilis co-infection in the brain function in young HIV patients by using voxel-wise degree centrality (DC) analysis.
Methods: Forty-four syphilis-co-infected HIV patients (HIV+/syphilis+), 45 HIV patients without syphilis history (HIV+/syphilis-) and 43 matched healthy controls (HC) underwent resting-state fMRI examinations. Laboratory tests and a battery of neuropsychological tests were performed before each MRI examination. One-way ANOVA was used to compare the differences of DC among the three groups. The correlations between MRI metrics and laboratory/neuropsychological tests in each patient's group were performed by Pearson correlation analysis.
Results: Compared with HIV+/syphilis-, worse performance in complex motor skills was found in HIV+/syphilis+. Compared with HC, HIV+/syphilis+ and HIV+/syphilis- groups showed attenuated DC in the right orbital frontal cortex and increased DC in the left parietal/temporal cortex. Besides, we also found increased DC in the left inferior frontal cortex and bilateral posterior cingulated cortex/precuneus in HIV+/syphilis+ compared with HC. Moreover, compared with HIV+/syphilis-, HIV+/syphilis+ displayed decreased DC in the left middle occipital cortex. Additionally, in HIV+/syphilis+ group, the mean z value of DC was correlated to the CD4+ cell counts and the learning and delayed recall score.
Conclusion: Syphilis co-infection might be related to more brain functional reorganization in young HIV patients which could be reflected by DC value.

PMID: 32210597 [PubMed]

Differentiating Boys with ADHD from Those with Typical Development Based on Whole-Brain Functional Connections Using a Machine Learning Approach.

Sat, 03/28/2020 - 03:37
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Differentiating Boys with ADHD from Those with Typical Development Based on Whole-Brain Functional Connections Using a Machine Learning Approach.

Neuropsychiatr Dis Treat. 2020;16:691-702

Authors: Sun Y, Zhao L, Lan Z, Jia XZ, Xue SW

Abstract
Purpose: In recent years, machine learning techniques have received increasing attention as a promising approach to differentiating patients from healthy subjects. Therefore, some resting-state functional magnetic resonance neuroimaging (R-fMRI) studies have used interregional functional connections as discriminative features. The aim of this study was to investigate ADHD-related spatially distributed discriminative features derived from whole-brain resting-state functional connectivity patterns using machine learning.
Patients and Methods: We measured the interregional functional connections of the R-fMRI data from 40 ADHD patients and 28 matched typically developing controls. Machine learning was used to discriminate ADHD patients from controls. Classification performance was assessed by permutation tests.
Results: The results from the model with the highest classification accuracy showed that 85.3% of participants were correctly identified using leave-one-out cross-validation (LOOV) with support vector machine (SVM). The majority of the most discriminative functional connections were located within or between the cerebellum, default mode network (DMN) and frontoparietal regions. Approximately half of the most discriminative connections were associated with the cerebellum. The cerebellum, right superior orbitofrontal cortex, left olfactory cortex, left gyrus rectus, right superior temporal pole, right calcarine gyrus and bilateral inferior occipital cortex showed the highest discriminative power in classification. Regarding the brain-behaviour relationships, some functional connections between the cerebellum and DMN regions were significantly correlated with behavioural symptoms in ADHD (P < 0.05).
Conclusion: This study indicated that whole-brain resting-state functional connections might provide potential neuroimaging-based information for clinically assisting the diagnosis of ADHD.

PMID: 32210565 [PubMed]

Impaired brain network architecture in Cushing's disease based on graph theoretical analysis.

Thu, 03/26/2020 - 21:36
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Impaired brain network architecture in Cushing's disease based on graph theoretical analysis.

Aging (Albany NY). 2020 Mar 24;12:

Authors: Xu CX, Jiang H, Zheng RZ, Sun YH, Sun QF, Bian LG

Abstract
To investigate the whole functional brain networks of active Cushing disease (CD) patients about topological parameters (small world and rich club et al.) and compared with healthy control (NC). Nineteen active CD patients and twenty-two healthy control subjects, matched in age, gender, and education, underwent resting-state fMRI. Graph theoretical analysis was used to calculate the functional brain network organizations for all participants, and those for active CD patients were compared for and NCs. Active CD patients revealed higher global efficiency, shortest path length and reduced cluster efficiency compared with healthy control. Additionally, small world organization was present in active CD patients but higher than healthy control. Moreover, rich club connections, feeder connections and local connections were significantly decreased in active CD patients. Functional network properties appeared to be disrupted in active CD patients compared with healthy control. Analyzing the changes that lead to abnormal network metrics will improve our understanding of the pathophysiological mechanisms underlying CD.

PMID: 32208364 [PubMed - as supplied by publisher]

World/self ambivalence: A shared mechanism in different subsets of psychotic experiences? Linking symptoms with resting-state fMRI.

Thu, 03/26/2020 - 21:36
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World/self ambivalence: A shared mechanism in different subsets of psychotic experiences? Linking symptoms with resting-state fMRI.

Psychiatry Res Neuroimaging. 2020 Mar 18;299:111068

Authors: Damiani S, Fusar-Poli L, Brondino N, Provenzani U, Baldwin H, Fusar-Poli P, Politi P

Abstract
The psychosis spectrum comprises heterogeneous disorders characterized by both world-related and self-related symptoms. How these symptoms may arise with similar features in spite of the different aetiologies is yet an unsolved question. In behavior narrative review, we compare three conditions characterized by psychotic experiences (schizophrenia, substance-use disorder and sensory-deprivation) searching for links between their phenomenological features and the mechanisms underlying their onset. Clinically, psychotic experiences are characterized by the reciprocal contamination of world- and self-related contents, termed 'world/self ambivalence'. Neuroimaging evidence suggests that the imbalance between stimuli-, self-, and attention-related functional networks (visual/auditory, default-mode, and salience network respectively) assumes central relevance in all the conditions considered. Phenomenology and neurobiology were thus interrelated in light of the reviewed literature, identifying two key neuronal mechanisms which may lead to world/self ambivalence. First, psychotic experiences are associated with the relative dominance of one network over the other (default-mode over auditory/visual networks, or vice-versa), prompting an excess of internal or external pressure to the experienced ambivalence between world and self. Second, an altered salience network resting-state functional connectivity could generate a dysregulation of the attentive fluctuations from self- to world-related activity, thus blurring the boundary between the environment and oneself, labelled the 'world/self boundary'.

PMID: 32208349 [PubMed - as supplied by publisher]

Gender-based functional connectivity differences in brain networks in childhood.

Mon, 03/23/2020 - 21:33
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Gender-based functional connectivity differences in brain networks in childhood.

Comput Methods Programs Biomed. 2020 Mar 13;192:105444

Authors: İçer S, Acer İ, Baş A

Abstract
BACKGROUND AND OBJECTIVE: Understanding the effect of gender differences on the brain can provide important information to characterize normal changes throughout life and to increase the likelihood of sex-specific approaches for neurological and psychiatric diseases. In this study, Functional Connectivity (FC), Amplitude of Low-Frequency Fluctuations (ALFF) and fractional ALFF (fALFF) analyzes will be compared between female and male brains between the ages of 7 and 18 years using resting state-functional magnetic resonance imaging (rs-fMRI).
METHODS: The rs-fMRI data in this study has been provided by The New York University (NYU) Child Study Center of the publicly shared ADHD200 database. From the NYU dataset, 68 (34 females, 34 males) healthy subjects in the age range of 7-18 years were selected. The female group (mean age: 12.3271±3.1380) and male group (mean age: 11.8766±2.9697) consisted of right-handed, small head motion and similar IQ values. FC was obtained by seed voxel analysis and the effect of low-frequency fluctuations on gender was examined by ALFF and fALFF analyses. Two-sample t-test was used to compare female and male groups with the significance thresholds set to FDR-corrected p<0.05.
RESULTS: In the results of our study, both in the ALFF, fALFF analyses and the seed regions belonging to many network regions, higher FC rates were found in girls than boys. Our results show that the females' language functions, visual functions such as object detection and recognition, working memory, executive functions, and episodic memory are more developed than males in this age range. In addition, as another result of our study, the seed regions are statistically stronger where the higher activation of female participants than male participants has concentrated in the left hemisphere.
CONCLUSIONS: Gender differences in brain networks should be taken into consideration when examining childhood cognitive and neuropsychiatric disorders and the results should also be evaluated according to gender. Evaluation of gender differences in childhood can increase the likelihood of early and definitive diagnosis and correct treatment for neurological diseases and can help doctors and scientists find new diagnostic tools to discover brain differences.

PMID: 32200049 [PubMed - as supplied by publisher]

Network Mapping of Connectivity Alterations in Disorder of Consciousness: Towards Targeted Neuromodulation.

Sun, 03/22/2020 - 21:32
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Network Mapping of Connectivity Alterations in Disorder of Consciousness: Towards Targeted Neuromodulation.

J Clin Med. 2020 Mar 18;9(3):

Authors: Mencarelli L, Biagi MC, Salvador R, Romanella S, Ruffini G, Rossi S, Santarnecchi E

Abstract
Disorder of consciousness (DoC) refers to a group of clinical conditions that may emerge after brain injury, characterized by a varying decrease in the level of consciousness that can last from days to years. An understanding of its neural correlates is crucial for the conceptualization and application of effective therapeutic interventions. Here we propose a quantitative meta-analysis of the neural substrate of DoC emerging from functional magnetic resonance (fMRI) and positron emission tomography (PET) studies. We also map the relevant networks of resulting areas to highlight similarities with Resting State Networks (RSNs) and hypothesize potential therapeutic solutions leveraging network-targeted noninvasive brain stimulation. Available literature was reviewed and analyzed through the activation likelihood estimate (ALE) statistical framework to describe resting-state or task-dependent brain activation patterns in DoC patients. Results show that task-related activity is limited to temporal regions resembling the auditory cortex, whereas resting-state fMRI data reveal a diffuse decreased activation affecting two subgroups of cortical (angular gyrus, middle frontal gyrus) and subcortical (thalamus, cingulate cortex, caudate nucleus) regions. Clustering of their cortical functional connectivity projections identify two main altered functional networks, related to decreased activity of (i) the default mode and frontoparietal networks, as well as (ii) the anterior salience and visual/auditory networks. Based on the strength and topography of their connectivity profile, biophysical modeling of potential brain stimulation solutions suggests the first network as the most feasible target for tES, tDCS neuromodulation in DoC patients.

PMID: 32197485 [PubMed - as supplied by publisher]