New resting-state fMRI related studies at PubMed

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Hippocampal functional connectivity-based discrimination between bipolar and major depressive disorders.

Sun, 01/27/2019 - 16:20
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Hippocampal functional connectivity-based discrimination between bipolar and major depressive disorders.

Psychiatry Res Neuroimaging. 2019 Jan 12;284:53-60

Authors: Fateh AA, Long Z, Duan X, Cui Q, Pang Y, Farooq MU, Nan X, Chen Y, Sheng W, Tang Q, Chen H

Abstract
Despite the impressive advancements in the neuropathology of mood disorders, patients with bipolar disorder (BD) are often misdiagnosed on the initial presentation with major depressive disorder (MDD). With supporting evidence from neuroimaging studies, the abnormal functional connectivity (FC) of the hippocampus has been associated with various mood disorders, including BD and MDD. However, the features of the hippocampal FC underlying MDD and BD have not been directly compared. This study aims to investigate the hippocampal resting-state FC (rsFC) analyses to distinguish these two clinical conditions. Resting-state functional magnetic resonance imaging (fMRI) data was collected from a sample group of 30 patients with BD, 29 patients with MDD and 30 healthy controls (HCs). One-way ANOVA was employed to assess the potential differences of the hippocampus FC across all subjects. BD patients exhibited increased FC of the bilateral anterior/posterior hippocampus with lingual gyrus and inferior frontal gyrus (IFG) relative to patients MDD patients. In comparison with HCs, patients with BD and MDD had an increased FC between the right anterior hippocampus and lingual gyrus and a decreased FC between the right posterior hippocampus and right IFG. The results revealed a distinct hippocampal FC in MDD patients compared with that observed in BD patients. These findings may assist investigators in attempting to distinguish mood disorders by using fMRI data.

PMID: 30684896 [PubMed - as supplied by publisher]

Increased functional segregation of brain network associated with symptomatology and sustained attention in chronic post-traumatic stress disorder.

Sun, 01/27/2019 - 16:20
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Increased functional segregation of brain network associated with symptomatology and sustained attention in chronic post-traumatic stress disorder.

J Affect Disord. 2019 Jan 17;247:183-191

Authors: Zhu H, Li Y, Yuan M, Ren Z, Yuan C, Meng Y, Wang J, Deng W, Qiu C, Huang X, Gong Q, Lui S, Zhang W

Abstract
BACKGROUND: Traditional regional or voxel-based analyses only focus on specific brain regions or connectivity rather than the whole brain's functional organization. Using resting state functional magnetic resonance imaging (rs-fMRI), we aimed to explore the altered topological metrics, clinical symptoms and cognitive function in chronic post-traumatic stress disorder (PTSD) in order to identify the brain network mechanisms underlying these clinical and cognitive symptoms.
METHODS: Forty patients with unmedicated chronic PTSD and forty-two matched trauma-exposed healthy controls (TEHCs) underwent rs-fMRI, and the topological organization of the whole-brain network was calculated using graph theory. The Rapid Visual Information Processing (RVP) task and Wechsler Memory Scale-IV (WMS-IV) were used to evaluate the subjects' sustained attention and memory capacity. All clinical and cognitive measures and topological parameters of the PTSD patients and TEHCs were compared, and the relationships between altered network metrics and symptom severity were explored.
RESULTS: Compared with the TEHCs, the patients showed increases in the normalized clustering coefficient, small-worldness, normalized local efficiency and efficiency-based small-worldness. The left middle occipital gyrus showed increases in nodal global efficiency and nodal degree that were negatively correlated with the severity of PTSD symptoms. The altered connections in PTSD only involved the default mode network (DMN) and the occipital network.
LIMITATIONS: Comorbid conditions were included, and current cross-sectional study cannot conclude on causality.
CONCLUSIONS: Patients with chronic PTSD showed increased functional brain network segregation, mainly in the occipital cortex, which could be a protective or compensatory mechanism to alleviate clinical symptoms.

PMID: 30684892 [PubMed - as supplied by publisher]

Active information storage in Parkinson's disease: a resting state fMRI study over the sensorimotor cortex.

Sun, 01/27/2019 - 16:20
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Active information storage in Parkinson's disease: a resting state fMRI study over the sensorimotor cortex.

Brain Imaging Behav. 2019 Jan 25;:

Authors: Puche Sarmiento AC, Bocanegra García Y, Ochoa Gómez JF

Abstract
Parkinson's disease (PD), the second most frequent neurodegenerative disease, affects significantly life quality by a combination of motor and cognitive disturbances. Although it is traditionally associated with basal ganglia dysfunction, cortical alterations are also involved in disease symptoms. Our objective is to evaluate the alterations in brain dynamics in de novo and recently treated PD subjects using a nonlinear method known as Active Information Storage. In the current research, Active Information Storage (AIS) was used to study the complex dynamics in motor cortex spontaneous activity captured using resting state functional Magnetic Resonance Imaging (rs-fMRI) at early-stage in non-medicated and recently medicated PD subjects. Supplementary to AIS, the fractional Amplitude of Low Frequency Fluctuation (fALFF), which is a better-established technique of analysis of rs-fMRI signals, was also evaluated. Compared to healthy subjects, the AIS values were significantly reduced in PD patients over the analyzed motor cortex regions; differences were also found at less extent using the fALFF measure. Correlations between AIS and fALFF values showed that the measures seem to capture similar neuronal phenomena in rs-fMRI data. The highest sensitivity when detecting group differences revealed by AIS, and not captured by traditional linear approaches, suggests that this measure is a promising tool for the analysis of rs-fMRI neural data in PD.

PMID: 30684153 [PubMed - as supplied by publisher]

Hyperactivity/restlessness is associated with increased functional connectivity in adults with ADHD: a dimensional analysis of resting state fMRI.

Sun, 01/27/2019 - 16:20
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Hyperactivity/restlessness is associated with increased functional connectivity in adults with ADHD: a dimensional analysis of resting state fMRI.

BMC Psychiatry. 2019 Jan 25;19(1):43

Authors: Sörös P, Hoxhaj E, Borel P, Sadohara C, Feige B, Matthies S, Müller HHO, Bachmann K, Schulze M, Philipsen A

Abstract
BACKGROUND: Adult attention-deficit/hyperactivity disorder (ADHD) is a serious and frequent psychiatric disorder of multifactorial pathogenesis. Several lines of evidence support the idea that ADHD is, in its core, a disorder of dysfunctional brain connectivity within and between several neurofunctional networks. The primary aim of this study was to investigate associations between the functional connectivity within resting state brain networks and the individual severity of core ADHD symptoms (inattention, hyperactivity, and impulsivity).
METHODS: Resting state functional magnetic resonance imaging (rs-fMRI) data of 38 methylphenidate-naïve adults with childhood-onset ADHD (20 women, mean age 40.5 years) were analyzed using independent component analysis (FSL's MELODIC) and FSL's dual regression technique. For motion correction, standard volume-realignment followed by independent component analysis-based automatic removal of motion artifacts (FSL's ICA-AROMA) were employed. To identify well-established brain networks, the independent components found in the ADHD group were correlated with brain networks previously found in healthy participants (Smith et al. PNAS 2009;106:13040-5). To investigate associations between functional connectivity and individual symptom severity, sex, and age, linear regressions were performed.
RESULTS: Decomposition of resting state brain activity of adults with ADHD resulted in similar resting state networks as previously described for healthy adults. No significant differences in functional connectivity were seen between women and men. Advanced age was associated with decreased functional connectivity in parts of the bilateral cingulate and paracingulate cortex within the executive control network. More severe hyperactivity was associated with increased functional connectivity in the left putamen, right caudate nucleus, right central operculum and a portion of the right postcentral gyrus within the auditory/sensorimotor network.
CONCLUSIONS: The present study supports and extends our knowledge on the involvement of the striatum in the pathophysiology of ADHD, in particular, in the pathogenesis of hyperactivity. Our results emphasize the usefulness of dimensional analyses in the study of ADHD, a highly heterogeneous disorder.
TRIAL REGISTRATION: ISRCTN12722296 ( https://doi.org/10.1186/ISRCTN12722296 ).

PMID: 30683074 [PubMed - in process]

Long-term Chinese calligraphic handwriting training has a positive effect on brain network efficiency.

Sun, 01/27/2019 - 16:20
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Long-term Chinese calligraphic handwriting training has a positive effect on brain network efficiency.

PLoS One. 2019;14(1):e0210962

Authors: Chen W, He Y, Chen C, Zhu M, Bi S, Liu J, Xia M, Lin Q, Wang Y, Wang W

Abstract
As a visual art form, Chinese calligraphic handwriting (CCH) has been found to correlate with certain brain activity and to induce functional connectivity reorganization of the brain. This study investigated the effect of long-term CCH training on brain functional plasticity as assessed with network measures. With the resting-state fMRI data from 31 participants with at least five years of CCH training and 40 controls, we constructed brain functional networks, examined group differences at both the whole brain and modular levels, and correlated the topological characteristics with calligraphy skills. We found that, compared to the control group, the CCH group showed shorter characteristic path lengths and higher local efficiency in certain brain areas in the frontal and parietal cortices, limbic system, basal ganglia, and thalamus. Moreover, these network measures in the cingulate cortex, caudate nucleus, and thalamus were associated with CCH performance (i.e., copying and creating skills). These results suggest that long-term CCH training has a positive effect on the topological characteristics of brain networks.

PMID: 30682084 [PubMed - in process]

Absence of dentate nucleus resting-state functional connectivity changes in nonneurological patients with gadolinium-related hyperintensity on T1 -weighted images.

Sun, 01/27/2019 - 16:20
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Absence of dentate nucleus resting-state functional connectivity changes in nonneurological patients with gadolinium-related hyperintensity on T1 -weighted images.

J Magn Reson Imaging. 2019 Jan 25;:

Authors: Mallio CA, Piervincenzi C, Gianolio E, Cirimele V, Papparella LG, Marano M, Quintiliani L, Aime S, Carducci F, Parizel PM, Quattrocchi CC

Abstract
BACKGROUND: The dentate nuclei of the cerebellum are the areas where gadolinium predominantly accumulates. It is not yet known whether gadolinium deposition affects brain functions.
PURPOSE/HYPOTHESIS: To assess whether gadolinium-dependent high signal intensity of the cerebellum on T1 -weighted images of nonneurological adult patients with Crohn's disease is associated with modifications of resting-state functional connectivity (RSFC) of the cerebellum and dentate nucleus.
STUDY TYPE: Observational, cross-sectional.
POPULATION: Fifteen patients affected by Crohn's disease were compared with 16 healthy age- and gender-matched control subjects. All participants underwent neurological, neurocognitive-psychological assessment, and blood sampling.
FIELD STRENGTH/SEQUENCE: 1.5-T magnet blood oxygenation level-dependent (BOLD) functional MRI.
ASSESSMENT: High signal intensity on T1 -weighted images, cerebellum functional connectivity, neurocognitive performance, and blood circulating gadolinium levels.
STATISTICAL TESTS: An unpaired two-sample t-test (age and sex were nuisance variables) was used to investigate between-group differences in cerebellar and dentate nucleus functional connectivity. Z-statistical images were set using clusters determined by Z > 2.3 and a familywise error (FWE)-corrected cluster significance threshold of P = 0.05.
RESULTS: Dentate nuclei RSFC was not different (P = n.s.) between patients with gadolinium-dependent high signal intensity on T1 -weighted images and controls. Pre- and postcentral gyrus bilaterally and the right supplementary motor cortex showed a decrease of RSFC with the cerebellum hemispheres (P < 0.05 FWE-corrected) and was related to disease duration but not to gadodiamide cumulative doses (P = n.s.).
DATA CONCLUSION: Crohn's disease patients with gadolinium-dependent hyperintense dentate nuclei on unenhanced T1 -weighted images do not show dentate nucleus RSFC changes.
LEVEL OF EVIDENCE: 2 Technical Efficacy Stage: 5.

PMID: 30681245 [PubMed - as supplied by publisher]

Transient states of network connectivity are atypical in autism: A dynamic functional connectivity study.

Sun, 01/27/2019 - 16:20
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Transient states of network connectivity are atypical in autism: A dynamic functional connectivity study.

Hum Brain Mapp. 2019 Jan 25;:

Authors: Mash LE, Linke AC, Olson LA, Fishman I, Liu TT, Müller RA

Abstract
There is ample evidence of atypical functional connectivity (FC) in autism spectrum disorders (ASDs). However, transient relationships between neural networks cannot be captured by conventional static FC analyses. Dynamic FC (dFC) approaches have been used to identify repeating, transient connectivity patterns ("states"), revealing spatiotemporal network properties not observable in static FC. Recent studies have found atypical dFC in ASDs, but questions remain about the nature of group differences in transient connectivity, and the degree to which states persist or change over time. This study aimed to: (a) describe and relate static and dynamic FC in typical development and ASDs, (b) describe group differences in transient states and compare them with static FC patterns, and (c) examine temporal stability and flexibility between identified states. Resting-state functional magnetic resonance imaging (fMRI) data were collected from 62 ASD and 57 typically developing (TD) children and adolescents. Whole-brain, data-driven regions of interest were derived from group independent component analysis. Sliding window analysis and k-means clustering were used to explore dFC and identify transient states. Across all regions, static overconnnectivity and increased variability over time in ASDs predominated. Furthermore, significant patterns of group differences emerged in two transient states that were not observed in the static FC matrix, with group differences in one state primarily involving sensory and motor networks, and in the other involving higher-order cognition networks. Default mode network segregation was significantly reduced in ASDs in both states. Results highlight that dynamic approaches may reveal more nuanced transient patterns of atypical FC in ASDs.

PMID: 30681228 [PubMed - as supplied by publisher]

Reward network connectivity "at rest" is associated with reward sensitivity in healthy adults: A resting-state fMRI study.

Sun, 01/27/2019 - 16:20
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Reward network connectivity "at rest" is associated with reward sensitivity in healthy adults: A resting-state fMRI study.

Cogn Affect Behav Neurosci. 2019 Jan 24;:

Authors: Adrián-Ventura J, Costumero V, Parcet MA, Ávila C

Abstract
The behavioral approach system (BAS), based on reinforcement sensitivity theory (RST), is a neurobehavioral system responsible for detecting and promoting motivated behaviors towards appetitive stimuli. Anatomically, the frontostriatal system has been proposed as the core of the BAS, mainly the ventral tegmental area and the ventral striatum and their dopaminergic connections with medial prefrontal structures. The RST also proposes the personality trait of reward sensitivity as a measurable construct of stable individual differences in BAS activity. However, the relationship between this trait and brain connectivity "at rest" has been poorly studied, mainly because previous investigations have focused on studying brain activity under reward-related contingency paradigms. Here, we analyzed the influence of reward sensitivity on the resting-state functional connectivity (rs-FC) between BAS-related areas by correlating the BOLD time series with the scores on the Sensitivity to Reward (SR) scale in a sample of 89 healthy young adults. Rs-FC between regions of interest were all significant. Results also revealed a positive association between SR scores and the rs-FC between the VTA and the ventromedial prefrontal cortex, and between the latter structure and the anterior cingulate cortex. These results suggest that reward sensitivity could be associated with different resting-state activity in the mesocortical pathway.

PMID: 30680664 [PubMed - as supplied by publisher]

The effects of lutein and zeaxanthin on resting state functional connectivity in older Caucasian adults: a randomized controlled trial.

Sun, 01/27/2019 - 16:20
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The effects of lutein and zeaxanthin on resting state functional connectivity in older Caucasian adults: a randomized controlled trial.

Brain Imaging Behav. 2019 Jan 24;:

Authors: Lindbergh CA, Lv J, Zhao Y, Mewborn CM, Puente AN, Terry DP, Renzi-Hammond LM, Hammond BR, Liu T, Miller LS

Abstract
The carotenoids lutein (L) and zeaxanthin (Z) accumulate in retinal regions of the eye and have long been shown to benefit visual health. A growing literature suggests cognitive benefits as well, particularly in older adults. The present randomized controlled trial sought to investigate the effects of L and Z on brain function using resting state functional magnetic resonance imaging (fMRI). It was hypothesized that L and Z supplementation would (1) improve intra-network integrity of default mode network (DMN) and (2) reduce inter-network connectivity between DMN and other resting state networks. 48 community-dwelling older adults (mean age = 72 years) were randomly assigned to receive a daily L (10 mg) and Z (2 mg) supplement or a placebo for 1 year. Resting state fMRI data were acquired at baseline and post-intervention. A dictionary learning and sparse coding computational framework, based on machine learning principles, was used to investigate intervention-related changes in functional connectivity. DMN integrity was evaluated by calculating spatial overlap rate with a well-established DMN template provided in the neuroscience literature. Inter-network connectivity was evaluated via time series correlations between DMN and nine other resting state networks. Contrary to expectation, results indicated that L and Z significantly increased rather than decreased inter-network connectivity (Cohen's d = 0.89). A significant intra-network effect on DMN integrity was not observed. Rather than restoring what has been described in the available literature as a "youth-like" pattern of intrinsic brain activity, L and Z may facilitate the aging brain's capacity for compensation by enhancing integration between networks that tend to be functionally segregated earlier in the lifespan.

PMID: 30680611 [PubMed - as supplied by publisher]

Neurometabolic and functional connectivity basis of prosocial behavior in early adolescence.

Sun, 01/27/2019 - 16:20
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Neurometabolic and functional connectivity basis of prosocial behavior in early adolescence.

Sci Rep. 2019 Jan 24;9(1):732

Authors: Okada N, Yahata N, Koshiyama D, Morita K, Sawada K, Kanata S, Fujikawa S, Sugimoto N, Toriyama R, Masaoka M, Koike S, Araki T, Kano Y, Endo K, Yamasaki S, Ando S, Nishida A, Hiraiwa-Hasegawa M, Edden RAE, Barker PB, Sawa A, Kasai K

Abstract
Human prosocial behavior (PB) emerges in childhood and matures during adolescence. Previous task-related functional magnetic resonance imaging (fMRI) studies have reported involvement of the medial prefrontal cortex including the anterior cingulate cortex (ACC) in social cognition in adolescence. However, neurometabolic and functional connectivity (FC) basis of PB in early adolescence remains unclear. Here, we measured GABA levels in the ACC and FC in a subsample (aged 10.5-13.4 years) of a large-scale population-based cohort with MR spectroscopy (MEGA-PRESS) and resting-state fMRI. PB was negatively correlated with GABA levels in the ACC (N = 221), and positively correlated with right ACC-seeded FC with the right precentral gyrus and the bilateral middle and posterior cingulate gyrus (N = 187). Furthermore, GABA concentrations and this FC were negatively correlated, and the FC mediated the association between GABA levels and PB (N = 171). Our results from a minimally biased, large-scale sample provide new insights into the neurometabolic and neurofunctional correlates of prosocial development during early adolescence.

PMID: 30679738 [PubMed - in process]

Repetitive Transcranial Electrical Stimulation Induces Quantified Changes in Resting Cerebral Perfusion Measured from Arterial Spin Labeling.

Sun, 01/27/2019 - 16:20
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Repetitive Transcranial Electrical Stimulation Induces Quantified Changes in Resting Cerebral Perfusion Measured from Arterial Spin Labeling.

Neural Plast. 2018;2018:5769861

Authors: Sherwood MS, Madaris AT, Mullenger CR, McKinley RA

Abstract
The use of transcranial electrical stimulation (TES) as a method to augment neural activity has increased in popularity in the last decade and a half. The specific application of TES to the left prefrontal cortex has been shown to produce broad cognitive effects; however, the neural mechanisms underlying these effects remain unknown. In this work, we evaluated the effect of repetitive TES on cerebral perfusion. Stimulation was applied to the left prefrontal cortex on three consecutive days, and resting cerebral perfusion was quantified before and after stimulation using arterial spin labeling. Perfusion was found to decrease significantly more in a matched sham stimulation group than in a group receiving active stimulation across many areas of the brain. These changes were found to originate in the locus coeruleus and were broadly distributed in the neocortex. The changes in the neocortex may be a direct result of the stimulation or an indirect result via the changes in the noradrenergic system produced from the altered activity of the locus coeruleus. These findings indicate that anodal left prefrontal stimulation alters the activity of the locus coeruleus, and this altered activity may excite the noradrenergic system producing the broad behavioral effects that have been reported.

PMID: 30254668 [PubMed - indexed for MEDLINE]

A domain-general brain network underlying emotional and cognitive interference processing: evidence from coordinate-based and functional connectivity meta-analyses.

Sun, 01/27/2019 - 16:20
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A domain-general brain network underlying emotional and cognitive interference processing: evidence from coordinate-based and functional connectivity meta-analyses.

Brain Struct Funct. 2018 Nov;223(8):3813-3840

Authors: Chen T, Becker B, Camilleri J, Wang L, Yu S, Eickhoff SB, Feng C

Abstract
The inability to control or inhibit emotional distractors characterizes a range of psychiatric disorders. Despite the use of a variety of task paradigms to determine the mechanisms underlying the control of emotional interference, a precise characterization of the brain regions and networks that support emotional interference processing remains elusive. Here, we performed coordinate-based and functional connectivity meta-analyses to determine the brain networks underlying emotional interference. Paradigms addressing interference processing in the cognitive or emotional domain were included in the meta-analyses, particularly the Stroop, Flanker, and Simon tasks. Our results revealed a consistent involvement of the bilateral dorsal anterior cingulate cortex, anterior insula, left inferior frontal gyrus, and superior parietal lobule during emotional interference. Follow-up conjunction analyses identified correspondence in these regions between emotional and cognitive interference processing. Finally, the patterns of functional connectivity of these regions were examined using resting-state functional connectivity and meta-analytic connectivity modeling. These regions were strongly connected as a distributed system, primarily mapping onto fronto-parietal control, ventral attention, and dorsal attention networks. Together, the present findings indicate that a domain-general neural system is engaged across multiple types of interference processing and that regulating emotional and cognitive interference depends on interactions between large-scale distributed brain networks.

PMID: 30083997 [PubMed - indexed for MEDLINE]

Local connectivity of the resting brain connectome in patients with low back-related leg pain: A multiscale frequency-related Kendall's coefficient of concordance and coherence-regional homogeneity study.

Fri, 01/25/2019 - 13:40

Local connectivity of the resting brain connectome in patients with low back-related leg pain: A multiscale frequency-related Kendall's coefficient of concordance and coherence-regional homogeneity study.

Neuroimage Clin. 2019 Jan 14;21:101661

Authors: Zhou F, Wu L, Guo L, Zhang Y, Zeng X

Abstract
Increasing evidence has suggested that central plasticity plays a crucial role in the development and maintenance of (chronic) nonspecific low back pain. However, it is unclear how local or short-distance functional interactions contribute to persisting low back-related leg pain (LBLP) due to a specific condition (i.e., lumbar disc herniation). In particular, the multiscale nature of local connectivity properties in various brain regions is still unclear. Here, we used voxelwise Kendall's coefficient of concordance (KCC) and coherence (Cohe) regional homogeneity (ReHo) in the typical (0.01-0.1 Hz) and five specific frequency (slow-6 to slow-2) bands to analyze individual whole-brain resting-state functional magnetic resonance imaging scans in 25 persistent LBLP patients (duration: 36.7 ± 9.6 months) and 26 healthy control subjects. Between-group differences demonstrated significant alterations in the KCC- and Cohe- ReHo of the right cerebellum posterior lobe, brainstem, left medial prefrontal cortex and bilateral precuneus in LBLP patients in the typical and five specific frequency bands, respectively, along with interactions between disease status and the five specific frequency bands in several regions of the pain matrix and the default-mode network (P < .01, Gaussian random field theory correction). The altered ReHo in the five specific frequency bands was correlated with the duration of pain and two-point discrimination, which were assessed using partial correlational analysis. These results linked the course of disease to the local connectivity properties in specific frequency bands in persisting LBLP. In future studies exploring local connectome association in pain conditions, integrated frequency bands and analytical methods should be considered.

PMID: 30677731 [PubMed - as supplied by publisher]

Extraction of time-varying spatio-temporal networks using parameter-tuned constrained IVA.

Fri, 01/25/2019 - 13:40

Extraction of time-varying spatio-temporal networks using parameter-tuned constrained IVA.

IEEE Trans Med Imaging. 2019 Jan 23;:

Authors: Bhinge S, Mowakeaa R, Calhoun VD, Adali T

Abstract
Dynamic functional connectivity (dFC) analysis is an effective way to capture the networks that are functionally associated and continuously changing over the scanning period. However, these methods mostly analyze the dynamic associations across the activation patterns of the spatial networks while assuming that the spatial networks are stationary. Hence, a model that allows for the variability in both domains and reduces the assumptions imposed on the data provides an effective way for extracting spatio-temporal networks. Independent vector analysis is a joint blind source separation technique that allows for estimation of spatial and temporal features while successfully preserving variability. However, its performance is affected for higher number of datasets. Hence, we develop an effective two-stage method to extract time-varying spatial and temporal features using IVA, mitigating the problems with higher number of datasets while preserving the variability across subjects and time. The first stage is used to extract reference signals using group independent component analysis (GICA) that are used in a parameter-tuned constrained IVA (pt-cIVA) framework to estimate time-varying representations of these signals by preserving the variability through tuning the constraint parameter. This approach effectively captures variability across time from a largescale resting-state fMRI data acquired from healthy controls and patients with schizophrenia and identifies more functionally relevant connections that are significantly different among healthy controls and patients with schizophrenia, compared with the widely used GICA method alone.

PMID: 30676948 [PubMed - as supplied by publisher]

BST1 rs4698412 allelic variant increases the risk of gait or balance deficits in patients with Parkinson's disease.

Fri, 01/25/2019 - 13:40

BST1 rs4698412 allelic variant increases the risk of gait or balance deficits in patients with Parkinson's disease.

CNS Neurosci Ther. 2019 Jan 24;:

Authors: Shen YT, Wang JW, Wang M, Zhi Y, Li JY, Yuan YS, Wang XX, Zhang H, Zhang KZ

Abstract
AIMS: We aimed to explore effects of bone marrow stromal cell antigen-1 (BST1) rs4698412 allelic variant on brain activation and associative clinical symptoms in Parkinson's disease (PD).
METHODS: A total of 49 PD patients and 47 healthy control (HC) subjects were recruited for clinical evaluations, blood samples collection for genotypes, and resting-state functional MRI (rs-fMRI) scans. Based on BST1 rs4698412 allelic variant (G → A), participants were further divided into 18 PD-GG, 31 PD-GA/AA, 20 HC-GG, and 27 HC-GA/AA carriers, which respectively indicated subjects carrying ancestral or risk allele in that locus in PD or HC. Two-way analysis of covariance (ANCOVA) was applied to investigate main effects and interactions between PD and BST1 rs4698412 allelic variant on brain function via amplitude of low-frequency fluctuations (ALFF). Spearman's correlations were then utilized to detect associations between interactive brain regions and clinical symptoms.
RESULTS: Compared to HC subjects, PD patients exhibited increased ALFF values in left cerebellum_8 and cerebellum_9. Significant interaction was in right lingual gyrus, where there were the lowest ALFF values and ALFF values were only negatively associated with Timed Up and Go (TUG) test time in PD-GA/AA subgroup.
CONCLUSION: BST1 rs4698412-modulated lingual gyrus functional alterations could be related to gait and balance dysfunction in PD.

PMID: 30676692 [PubMed - as supplied by publisher]

Physical characteristics not psychological state or trait characteristics predict motion during resting state fMRI.

Fri, 01/25/2019 - 13:40

Physical characteristics not psychological state or trait characteristics predict motion during resting state fMRI.

Sci Rep. 2019 Jan 23;9(1):419

Authors: Ekhtiari H, Kuplicki R, Yeh HW, Paulus MP

Abstract
Head motion (HM) during fMRI acquisition can significantly affect measures of brain activity or connectivity even after correction with preprocessing methods. Moreover, any systematic relationship between HM and variables of interest can introduce systematic bias. There is a large and growing interest in identifying neural biomarkers for psychiatric disorders using resting state fMRI (rsfMRI). However, the relationship between HM and different psychiatric symptoms domains is not well understood. The aim of this investigation was to determine whether psychiatric symptoms and other characteristics of the individual predict HM during rsfMRI. A sample of n = 464 participants (174 male) from the Tulsa1000, a naturalistic longitudinal study recruiting subjects with different levels of severity in mood/anxiety/substance use disorders based on the dimensional NIMH Research Domain Criteria framework was used for this study. Based on a machine learning (ML) pipeline with nested cross-validation to avoid overfitting, the stacked model with 15 anthropometric (like body mass index, BMI) and demographic (age and sex) variables identifies BMI and weight as the most important variables and explained 10.9 percent of the HM variance (95% CI: 9.9-11.8). In comparison ML models with 105 self-report measures for state and trait psychological characteristics identified nicotine and alcohol use variables as well as impulsivity inhibitory control variables but explain only 5 percent of HM variance (95% CI: 3.5-6.4). A combined ML model using all 120 variables did not perform significantly better than the model using only 15 physical variables (combined model 95% confidence interval: 10.2-12.4). Taken together, after considering physical variables, state or trait psychological characteristics do not provide additional power to predict motion during rsfMRI.

PMID: 30674933 [PubMed - in process]

Prognostication of chronic disorders of consciousness using brain functional networks and clinical characteristics.

Fri, 01/25/2019 - 13:40
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Prognostication of chronic disorders of consciousness using brain functional networks and clinical characteristics.

Elife. 2018 08 14;7:

Authors: Song M, Yang Y, He J, Yang Z, Yu S, Xie Q, Xia X, Dang Y, Zhang Q, Wu X, Cui Y, Hou B, Yu R, Xu R, Jiang T

Abstract
Disorders of consciousness are a heterogeneous mixture of different diseases or injuries. Although some indicators and models have been proposed for prognostication, any single method when used alone carries a high risk of false prediction. This study aimed to develop a multidomain prognostic model that combines resting state functional MRI with three clinical characteristics to predict one year-outcomes at the single-subject level. The model discriminated between patients who would later recover consciousness and those who would not with an accuracy of around 88% on three datasets from two medical centers. It was also able to identify the prognostic importance of different predictors, including brain functions and clinical characteristics. To our knowledge, this is the first reported implementation of a multidomain prognostic model that is based on resting state functional MRI and clinical characteristics in chronic disorders of consciousness, which we suggest is accurate, robust, and interpretable.

PMID: 30106378 [PubMed - indexed for MEDLINE]

Correlation between intrinsic brain activity and thyroid-stimulating hormone level in unmedicated bipolar II depression.

Thu, 01/24/2019 - 12:20

Correlation between intrinsic brain activity and thyroid-stimulating hormone level in unmedicated bipolar II depression.

Neuroendocrinology. 2019 Jan 23;:

Authors: Zhong S, Chen G, Zhao L, Jia Y, Chen F, Qi Z, Huang L, Wang Y

Abstract
<br>Background/aims: Although abnormalities of amplitude of low-frequency fluctuations (ALFF) and hormone levels of hypothalamus-pituitary-thyroid (HPT) axis have been reported in patients with bipolar disorder (BD). However, the associations between abnormal ALFF and serum thyroid hormone levels remain unknown.
METHOD: Ninety patients with unmedicated BD II depression and 100 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging (rs-fMRI), and then routine band (0.01-0.1Hz), slow 5 band (0.01-0.027Hz) and slow 4 band (0.027-0.073Hz) ALFF analysis were performed. Additionally, serum thyroid hormone levels including free tri-iodothyronine (FT3), total tri-iodothyronine (TT3), free thyroxin (FT4), total thyroxin (TT4) and thyroid-stimulating hormone (TSH), were detected. Then the correlation between abnormal serum thyroid hormone levels and ALFF values in patients with BD II depression was calculated.
RESULTS: Compared with the HCs, the patients with BD II depression showed decreased ALFF in the bilateral precuneus (PCu)/posterior cingulate cortex (PCC) in routine and slow-4 frequency bands, decreased ALFF in the right PCu and increased ALFF in the right middle occipital gyrus (MOG) in the slow-5 frequency band. Additionally, the patients with BD II depression showed lower TSH level than HCs, and TSH level was positively correlated with ALFF values in the bilateral PCu/PCC in the routine frequency band.
CONCLUSIONS: These findings suggest that the patients with BD II depression display intrinsic activity abnormalities mainly in the PCu/PCC and MOG which are associated with specific frequency bands. Moreover, altered intrinsic activity in the PCu/PCC may be related to TSH levels in bipolar II depression. <br>.

PMID: 30673659 [PubMed - as supplied by publisher]

The Cerebellar Predictions for Social Interactions: Theory of Mind Abilities in Patients With Degenerative Cerebellar Atrophy.

Thu, 01/24/2019 - 12:20
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The Cerebellar Predictions for Social Interactions: Theory of Mind Abilities in Patients With Degenerative Cerebellar Atrophy.

Front Cell Neurosci. 2018;12:510

Authors: Clausi S, Olivito G, Lupo M, Siciliano L, Bozzali M, Leggio M

Abstract
Recent studies have focused on the role of the cerebellum in the social domain, including in Theory of Mind (ToM). ToM, or the "mentalizing" process, is the ability to attribute mental states, such as emotion, intentions and beliefs, to others to explain and predict their behavior. It is a fundamental aspect of social cognition and crucial for social interactions, together with more automatic mechanisms, such as emotion contagion. Social cognition requires complex interactions between limbic, associative areas and subcortical structures, including the cerebellum. It has been hypothesized that the typical cerebellar role in adaptive control and predictive coding could also be extended to social behavior. The present study aimed to investigate the social cognition abilities of patients with degenerative cerebellar atrophy to understand whether the cerebellum acts in specific ToM components playing a role as predictive structure. To this aim, an ad hoc social cognition battery was administered to 27 patients with degenerative cerebellar pathology and 27 healthy controls. In addition, 3D T1-weighted and resting-state fMRI scans were collected to characterize the structural and functional changes in cerebello-cortical loops. The results evidenced that the patients were impaired in lower-level processes of immediate perception as well as in the more complex conceptual level of mentalization. Furthermore, they presented a pattern of GM reduction in cerebellar portions that are involved in the social domain such as crus I-II, lobule IX and lobule VIIIa. These areas showed decreased functional connectivity with projection cerebral areas involved in specific aspects of social cognition. These findings boost the idea that the cerebellar modulatory function on the cortical projection areas subtends the social cognition process at different levels. Particularly, regarding the lower-level processes, the cerebellum may act by implicitly matching the external information (i.e., expression of the eyes) with the respective internal representation to guarantee an immediate judgment about the mental state of others. Otherwise, at a more complex conceptual level, the cerebellum seems to be involved in the construction of internal models of mental processes during social interactions in which the prediction of sequential events plays a role, allowing us to anticipate the other person's behavior.

PMID: 30670949 [PubMed]

Towards fast and reliable simultaneous EEG-fMRI analysis of epilepsy with automatic spike detection.

Wed, 01/23/2019 - 18:00
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Towards fast and reliable simultaneous EEG-fMRI analysis of epilepsy with automatic spike detection.

Clin Neurophysiol. 2018 Dec 17;130(3):368-378

Authors: Omidvarnia A, Kowalczyk MA, Pedersen M, Jackson GD

Abstract
OBJECTIVE: The process of manually marking up epileptic spikes for simultaneous electroencephalogram (EEG) and resting state functional MRI (rsfMRI) analysis in epilepsy studies is a tedious and subjective task for a human expert. The aim of this study was to evaluate whether automatic EEG spike detection can facilitate EEG-rsfMRI analysis, and to assess its potential as a clinical tool in epilepsy.
METHODS: We implemented a fast algorithm for detection of uniform interictal epileptiform discharges (IEDs) in one-hour scalp EEG recordings of 19 refractory focal epilepsy datasets (from 16 patients) who underwent a simultaneous EEG-rsfMRI recording. Our method was based on matched filtering of an IED template (derived from human markup) used to automatically detect other 'similar' EEG events. We compared simultaneous EEG-rsfMRI results between automatic IED detection and standard analysis with human EEG markup only.
RESULTS: In contrast to human markup, automatic IED detection takes a much shorter time to detect IEDs and export an output text file containing spike timings. In 13/19 focal epilepsy datasets, statistical EEG-rsfMRI maps based on automatic spike detection method were comparable with human markup, and in 6/19 focal epilepsy cases automatic spike detection revealed additional brain regions not seen with human EEG markup. Additional events detected by our automated method independently revealed similar patterns of activation to a human markup. Overall, automatic IED detection provides greater statistical power in EEG-rsfMRI analysis compared to human markup in a short timeframe.
CONCLUSIONS: Automatic spike detection is a simple and fast method that can reproduce comparable and, in some cases, even superior results compared to the common practice of manual EEG markup in EEG-rsfMRI analysis of epilepsy.
SIGNIFICANCE: Our study shows that IED detection algorithms can be effectively used in epilepsy clinical settings. This work further helps in translating EEG-rsfMRI research into a fast, reliable and easy-to-use clinical tool for epileptologists.

PMID: 30669013 [PubMed - as supplied by publisher]

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