New resting-state fMRI related studies at PubMed

Subscribe to New resting-state fMRI related studies at PubMed feed New resting-state fMRI related studies at PubMed
NCBI: db=pubmed; Term=resting state fMRI
Updated: 1 hour 4 min ago

Reduced resting-state functional connectivity of the basolateral amygdala to the medial prefrontal cortex in preweaning rats exposed to chronic early-life stress.

1 hour 4 min ago
Related Articles

Reduced resting-state functional connectivity of the basolateral amygdala to the medial prefrontal cortex in preweaning rats exposed to chronic early-life stress.

Brain Struct Funct. 2018 Jul 21;:

Authors: Guadagno A, Kang MS, Devenyi GA, Mathieu AP, Rosa-Neto P, Chakravarty M, Walker CD

Abstract
Early-life stress (ELS) exposure has long-term consequences for both brain structure and function and impacts cognitive and emotional behavior. The basolateral amygdala (BLA) plays an important role in anxiety and fear conditioning through its extensive anatomical and functional connections, in particular to the medial prefrontal cortex (mPFC). However, how ELS affects amygdala function and connectivity in developing rats is unknown. We used the naturalistic limited bedding/nesting (LB) paradigm to induce chronic stress in the pups between postnatal day (PND) 1-10. Male normal bedding (NB, control) or LB offspring underwent structural and resting-state functional MRI (rs-fMRI) on PND18 and in adulthood (PND74-76). Adult male rats were tested for fear conditioning and extinction behavior prior to scanning. Seed-based functional connectivity maps were generated based on four BLA seeds (left, right, anterior and posterior). At both ages, LB induced different effects on anterior and posterior BLA networks, with significant reductions in rs-fMRI connectivity between the anterior BLA and mPFC in LB compared to NB offspring. BLA connectivity was lateralized by preweaning age, with the right hemisphere displaying more connectivity changes than the left. Weak negative volumetric correlations between the BLA and mPFC were also present, mostly in preweaning LB animals. rs-fMRI connectivity and volumetric changes were associated with enhanced fear behaviors in adult LB offspring. Activation of the LB-exposed neonatal amygdala described previously might accelerate the maturation of BLA-mPFC projections and/or modify the activity of reciprocal connections between these structures, leading to a net reduction in rs-fMRI connectivity and increased fear behavior.

PMID: 30032360 [PubMed - as supplied by publisher]

Transcranial direct current stimulation (tDCS) facilitates verb learning by altering effective connectivity in the healthy brain.

Sun, 07/22/2018 - 13:20
Related Articles

Transcranial direct current stimulation (tDCS) facilitates verb learning by altering effective connectivity in the healthy brain.

Neuroimage. 2018 Jul 17;:

Authors: Fiori V, Kunz L, Kuhnke P, Marangolo P, Hartwigsen G

Abstract
Recent studies have shown that the left inferior frontal gyrus (IFG) plays a key role in language learning. Facilitatory stimulation over this region by means of anodal transcranial direct current stimulation (tDCS) can modulate linguistic abilities in healthy individuals and improve language performance in patients with post-stroke aphasia. Neuroimaging studies in healthy participants have suggested that anodal tDCS decreases task-related activity at the stimulated site when applied during different language tasks, and changes resting-state connectivity in a larger network of areas associated with language processing. However, to date, the neural correlates of the potential beneficial effects of tDCS on verb learning remain unclear. The current study investigated how anodal tDCS during verb learning modulates task-related activity and effective connectivity in the healthy language network. To this end, we combined a verb learning paradigm during functional neuroimaging with simultaneous tDCS over the left IFG in healthy human volunteers. We found that, relative to sham stimulation, anodal tDCS significantly decreased task-related activity at the stimulated left IFG and in the right homologue. Effective connectivity analysis showed that anodal tDCS significantly decreased task-related functional coupling between the left IFG and the right insula. Importantly, the individual decrease in connectivity was significantly correlated with the individual behavioural improvement during anodal tDCS. These results demonstrate, for the first time, that the behavioural improvements induced by anodal tDCS might be related to an overall decrease in processing effort both with respect to task-related activity and effective connectivity within a large language network.

PMID: 30030198 [PubMed - as supplied by publisher]

The structural basis of semantic control: Evidence from individual differences in cortical thickness.

Sun, 07/22/2018 - 13:20
Related Articles

The structural basis of semantic control: Evidence from individual differences in cortical thickness.

Neuroimage. 2018 Jul 17;:

Authors: Wang X, Bernhardt BC, Karapanagiotidis T, De Caso I, Rene Del Jesus Gonzalez Alam T, Cotter Z, Smallwood J, Jefferies E

Abstract
Semantic control allows us to shape our conceptual retrieval to suit the circumstances in a flexible way. Tasks requiring semantic control activate a large-scale network including left inferior prefrontal gyrus (IFG) and posterior middle temporal gyrus (pMTG) - this network responds when retrieval is focussed on weak as opposed to dominant associations. However, little is known about the biological basis of individual differences in this cognitive capacity: regions that are commonly activated in task-based fMRI may not relate to variation in controlled retrieval. The current study combined analyses of MRI-based cortical thickness with resting-state fMRI connectivity to identify structural markers of individual differences in semantic control. We found that participants who performed relatively well on tests of controlled semantic retrieval showed increased structural covariance between left pMTG and left anterior middle frontal gyrus (aMFG). This pattern of structural covariance was specific to semantic control and did not predict performance when harder non-semantic judgements were contrasted with easier semantic judgements. The intrinsic functional connectivity of these two regions forming a structural covariance network overlapped with previously-described semantic control regions, including bilateral IFG and intraparietal sulcus, and left posterior temporal cortex. These results add to our knowledge of the neural basis of semantic control in three ways: (i) Semantic control performance was predicted by the structural covariance network of left pMTG, a site that is less consistently activated than left IFG across studies. (ii) Our results provide further evidence that semantic control is at least partially separable from domain-general executive control. (iii) More flexible patterns of memory retrieval occurred when pMTG co-varied with distant regions inaMFG, as opposed to nearby visual, temporal or parietal lobe regions, providing further evidence that left prefrontal and posterior temporal areas form a distributed network for semantic control.

PMID: 30030197 [PubMed - as supplied by publisher]

Structural and functional abnormality of the putamen in children with developmental dyslexia.

Sun, 07/22/2018 - 13:20
Related Articles

Structural and functional abnormality of the putamen in children with developmental dyslexia.

Neuropsychologia. 2018 Jul 17;:

Authors: Wang Z, Yan X, Liu Y, Spray GJ, Deng Y, Cao F

Abstract
There is currently debate with regards to the role of phonological deficit in Chinese reading difficulty, even though some researchers have suggested that the deficit of phonological processing is also a signature of developmental dyslexia in Chinese, as has been found in alphabetic languages. In this study, we examined the brain mechanisms of phonological deficit in Chinese children with developmental dyslexia (DD) during an auditory rhyming judgment task. First, we examined structural differences in Chinese dyslexia by comparing gray and white matter volume in Chinese children with DD, age-matched controls (AC), and reading-matched controls (RC). Next, we examined whether the regions with an abnormal volume in DD showed deficient functional connectivity with the rest of the brain during a phonological task (i.e. auditory rhyming judgment). We found that both AC and RC had greater gray matter volume (GMV) at the left putamen and right dorsal lateral frontal cortex than DD, suggesting possible neural signatures of developmental dyslexia. Functional connectivity analysis revealed that the left putamen was more connected with the right inferior occipital gyrus (IOG) in AC and RC than in DD, suggesting that automatic orthographic involvement during spoken language processing is more salient in controls, while the left putamen was more connected with the left transverse temporal gyrus (TTG) and left insula in DD than in AC and RC, suggesting the phonological articulation -auditory feedback loop is more involved in DD. These findings suggest that the reduced left putamen might contribute to phonological deficits experienced in DD, since it showed deficient connectivity with the rest of the brain during phonological processing.

PMID: 30030195 [PubMed - as supplied by publisher]

Dopamine, time perception, and future time perspective.

Sun, 07/22/2018 - 13:20
Related Articles

Dopamine, time perception, and future time perspective.

Psychopharmacology (Berl). 2018 Jul 19;:

Authors: Mitchell JM, Weinstein D, Vega T, Kayser AS

Abstract
RATIONALE: Impairment in time perception, a critical component of decision-making, represents a risk factor for psychiatric conditions including substance abuse. A therapeutic that ameliorates this impairment could be advantageous in the treatment of impulsivity and decision-making disorders.
OBJECTIVES: Here we hypothesize that the catechol-O-methyltransferase (COMT) inhibitor tolcapone, which increases dopamine tone in frontal cortex (Ceravolo et al Synapse 43:201-207, 2002), improves time perception, with predictive behavioral, genetic, and neurobiological components.
METHODS: Subjects (n = 66) completed a duration estimation task and other behavioral testing in each of two sessions after receiving a single oral dose of tolcapone (200 mg) or placebo in randomized, double-blind, counterbalanced, crossover fashion. Resting state fMRI data were obtained in a subset of subjects (n = 40). Subjects were also genotyped for the COMT (rs4680) polymorphism.
RESULTS: Time perception was significantly improved across four proximal time points ranging from 5 to 60 s (T(524) = 2.04, p = 0.042). The degree of this improvement positively correlated with subjective measures of stress, depression, and alcohol consumption and was most robust in carriers of the COMT Val158 allele. Using seed regions defined by a previous meta-analysis (Wiener et al Neuroimage 49:1728-1740, 2010), we found not only that a connection from right inferior frontal gyrus (RIFG) to right putamen decreases in strength on tolcapone versus placebo (p < 0.05, corrected), but also that the strength of this decrease correlates inversely with the increase in duration estimation on tolcapone versus placebo (r = - 0.37, p = 0.02).
CONCLUSIONS: Compressed time perception can be ameliorated by administration of tolcapone. Additional studies should be conducted to determine whether COMT inhibitors may be effective in treating decision-making disorders and addictive behaviors.

PMID: 30027496 [PubMed - as supplied by publisher]

Theoretical Modeling of Cognitive Dysfunction in Schizophrenia by Means of Errors and Corresponding Brain Networks.

Sun, 07/22/2018 - 13:20
Related Articles

Theoretical Modeling of Cognitive Dysfunction in Schizophrenia by Means of Errors and Corresponding Brain Networks.

Front Psychol. 2018;9:1027

Authors: Zaytseva Y, Fajnerová I, Dvořáček B, Bourama E, Stamou I, Šulcová K, Motýl J, Horáček J, Rodriguez M, Španiel F

Abstract
The current evidence of cognitive disturbances and brain alterations in schizophrenia does not provide the plausible explanation of the underlying mechanisms. Neuropsychological studies outlined the cognitive profile of patients with schizophrenia, that embodied the substantial disturbances in perceptual and motor processes, spatial functions, verbal and non-verbal memory, processing speed and executive functioning. Standardized scoring in the majority of the neurocognitive tests renders the index scores or the achievement indicating the severity of the cognitive impairment rather than the actual performance by means of errors. At the same time, the quantitative evaluation may lead to the situation when two patients with the same index score of the particular cognitive test, demonstrate qualitatively different performances. This may support the view why test paradigms that habitually incorporate different cognitive variables associate weakly, reflecting an ambiguity in the interpretation of noted cognitive constructs. With minor exceptions, cognitive functions are not attributed to the localized activity but eventuate from the coordinated activity in the generally dispersed brain networks. Functional neuroimaging has progressively explored the connectivity in the brain networks in the absence of the specific task and during the task processing. The spatio-temporal fluctuations of the activity of the brain areas detected in the resting state and being highly reproducible in numerous studies, resemble the activation and communication patterns during the task performance. Relatedly, the activation in the specific brain regions oftentimes is attributed to a number of cognitive processes. Given the complex organization of the cognitive functions, it becomes crucial to designate the roles of the brain networks in relation to the specific cognitive functions. One possible approach is to identify the commonalities of the deficits across the number of cognitive tests or, common errors in the various tests and identify their common "denominators" in the brain networks. The qualitative characterization of cognitive performance might be beneficial in addressing diffuse cognitive alterations presumably caused by the dysconnectivity of the distributed brain networks. Therefore, in the review, we use this approach in the description of standardized tests in the scope of potential errors in patients with schizophrenia with a subsequent reference to the brain networks.

PMID: 30026711 [PubMed]

Total Salvianolic Acid Balances Brain Functional Network Topology in Rat Hippocampi Overexpressing miR-30e.

Sun, 07/22/2018 - 13:20
Related Articles

Total Salvianolic Acid Balances Brain Functional Network Topology in Rat Hippocampi Overexpressing miR-30e.

Front Neurosci. 2018;12:448

Authors: Li Q, Wang L, Li XY, Chen X, Lu B, Cheng L, Yan CG, Xu Y

Abstract
We investigated the therapeutic effects and underlying brain functional network topology mechanisms of total salvianolic acid (TSA) treatment for memory dysfunction by using miR-30e overexpression-induced memory deficit in rat hippocampi. Model rats were developed by lentivirus vectors carrying miR-30e into bilateral hippocampus CA1 region through stereo-surgery. Two weeks after surgery, TSA (20 or 10 mg/mL/kg) or saline were administrated for 14 consecutive days. Memory function was assessed by behavioral tests (Y maze and Morris water maze [MWM]); resting-state functional MRI (RS-fMRI); and molecular alterations of BCL-2, UBC9, and Caspase-3 in the hippocampus CA1 region, as detected by immunohistochemistry. Compared to controls, model rats exhibited significantly impaired working and long-term memory in the Y maze and MWM tests (p < 0.01). The brain functional network topology analyzed based on RS-fMRI data demonstrated that miR-30e disturbed the global integration and segregation balance of the brain (p < 0.01), and reduced edge strength between CA1 and the posterior cingulate, temporal lobe, and thalamus (p < 0.05, false discovery rate corrected). At the molecular level, BCL-2 and UBC9 were downregulated, while Caspase-3 was upregulated (p < 0.01). After TSA (20 mg/mL/kg) treatment, the biomarkers for behavioral performance, global integration and segregation, edge strength, and expression levels of BCL-2, UBC9, and Caspase3 returned to normal levels. The correlation analyses of these results showed that global brain functional network topologic parameters can be intermediate biomarkers correlated with both behavioral changes and molecular alterations. This indicated that the effects of TSA were achieved by inhibiting apoptosis of CA1 neurons to improve global functional network topology.

PMID: 30026682 [PubMed]

Disrupted coupling of large-scale networks is associated with relapse behaviour in heroin-dependent men.

Sun, 07/22/2018 - 13:20
Related Articles

Disrupted coupling of large-scale networks is associated with relapse behaviour in heroin-dependent men.

J Psychiatry Neurosci. 2018 Jan;43(1):48-57

Authors: Li Q, Liu J, Wang W, Wang Y, Li W, Chen J, Zhu J, Yan X, Li Y, Li Z, Ye J, Wang W

Abstract
BACKGROUND: It is unknown whether impaired coupling among 3 core large-scale brain networks (salience [SN], default mode [DMN] and executive control networks [ECN]) is associated with relapse behaviour in treated heroin-dependent patients.
METHODS: We conducted a prospective resting-state functional MRI study comparing the functional connectivity strength among healthy controls and heroin-dependent men who had either relapsed or were in early remission. Men were considered to be either relapsed or in early remission based on urine drug screens during a 3-month follow-up period. We also examined how the coupling of large-scale networks correlated with relapse behaviour among heroin-dependent men.
RESULTS: We included 20 controls and 50 heroin-dependent men (26 relapsed and 24 early remission) in our analyses. The relapsed men showed greater connectivity than the early remission and control groups between the dorsal anterior cingulate cortex (key node of the SN) and the dorsomedial prefrontal cortex (included in the DMN). The relapsed men and controls showed lower connectivity than the early remission group between the left dorsolateral prefrontal cortex (key node of the left ECN) and the dorsomedial prefrontal cortex. The percentage of positive urine drug screens positively correlated with the coupling between the dorsal anterior cingulate cortex and dorsomedial prefrontal cortex, but negatively correlated with the coupling between the left dorsolateral prefrontal cortex and dorsomedial prefrontal cortex.
LIMITATIONS: We examined deficits in only 3 core networks leading to relapse behaviour. Other networks may also contribute to relapse.
CONCLUSION: Greater coupling between the SN and DMN and lower coupling between the left ECN and DMN is associated with relapse behaviour. These findings may shed light on the development of new treatments for heroin addiction.

PMID: 29252165 [PubMed - indexed for MEDLINE]

Orbitofrontal connectivity is associated with depression and anxiety in marijuana-using adolescents.

Fri, 07/20/2018 - 11:20

Orbitofrontal connectivity is associated with depression and anxiety in marijuana-using adolescents.

J Affect Disord. 2018 Jul 03;239:234-241

Authors: Subramaniam P, Rogowska J, DiMuzio J, Lopez-Larson M, McGlade E, Yurgelun-Todd D

Abstract
BACKGROUND: Prevalence of marijuana (MJ) use among adolescents has been on the rise. MJ use has been reported to impact several brain regions, including frontal regions such as the orbitofrontal cortex (OFC). The OFC is involved in emotion regulation and processing and has been associated with symptoms of depression and anxiety. Therefore, we hypothesized that adolescent MJ users would show disruptions in OFC connectivity compared with healthy adolescents (HC) which would be associated with symptoms of mood and anxiety.
METHODS: 43 MJ-using and 31 HC adolescents completed clinical measures including the Hamilton Anxiety Scale (HAM-A) and Hamilton Depression Rating Scale (HAM-D). Resting-state functional magnetic resonance imaging data was also acquired for all participants.
RESULTS: In MJ users, increased depressive symptoms were associated with increased connectivity between the left OFC and left parietal regions. In contrast, lower ratings of anxiety were associated with increased connectivity between right and left OFC and right occipital and temporal regions. These findings indicate significant differences in OFC connectivity in MJ-using adolescents, which correlated with mood/anxiety.
LIMITATIONS: Future studies with an increased number of female participants is required to address potential sex differences in connectivity patterns related to symptoms of depression and anxiety.
CONCLUSIONS: This study highlights the association between OFC connectivity, MJ use, and symptoms of depression and anxiety in adolescents. These findings provide further insight into understanding the neural correlates that modulate the relationship between comorbid MJ use and mood disorders and could potentially help us better develop preventive and treatment measures.

PMID: 30025312 [PubMed - as supplied by publisher]

Resting state fMRI reveals the altered synchronization of BOLD signals in essential tremor.

Fri, 07/20/2018 - 11:20

Resting state fMRI reveals the altered synchronization of BOLD signals in essential tremor.

J Neurol Sci. 2018 Jul 10;392:69-76

Authors: Wang P, Luo X, Zhong C, Yang L, Guo F, Yu N

Abstract
Essential tremor (ET) is one of the most common movement disorders in humans. Nevertheless, there remain several controversies surrounding ET, such as whether it is a disorder of abnormal neuronal oscillations within the tremor network. In this work, the resting-state fMRI data were collected from 17 ET patients and 17 age- and gender-matched healthy controls. First, using FOur-dimensional (spatiotemporal) Consistency of local neural Activities (FOCA) the abnormal synchronization of fMRI signals in ET patients were investigated. Then, global functional connectivity intensity (gFCI) and density (gFCD) were analyzed in the regions exhibiting significant FOCA differences. Compared with healthy controls, patients with ET showed the increased FOCA values found in the bilateral cuneus, the left lingual gyrus, the left paracentral lobule, the right middle temporal gyrus, the bilateral precentral gyrus, the right postcentral gyrus, the pallidum and putamen. Decreased FOCA values in ET patients were located in the frontal gyrus, the bilateral anterior cingulate and the medial dorsal nucleus of right thalamus. In ET patients, significant changes in gFCI and gFCD were located in the cuneus, the middle temporal gyrus and the middle frontal gyrus. Changes in gFCI were also found in the medial frontal gyrus and thalamus in addition to changes in gFCD in the precentral gyrus. Our results provided further evidence that ET might present with abnormal spontaneous activity in the tremor network, including motor-related cotex, basal ganglia and thalamus, as well as distributed non-motor areas. This work also demonstrated that FOCA and functional connectivity have the potential to provide important insight into the pathophysiological mechanism of ET.

PMID: 30025236 [PubMed - as supplied by publisher]

Longitudinal resting state functional connectivity predicts clinical outcome in mild traumatic brain injury.

Fri, 07/20/2018 - 11:20

Longitudinal resting state functional connectivity predicts clinical outcome in mild traumatic brain injury.

J Neurotrauma. 2018 Jul 19;:

Authors: Madhavan R, Joel SE, Mullick R, Cogsil T, Niogi S, Tsiouris AJ, Mukherjee P, Masdeu JC, Marinelli L, Shetty T

Abstract
Mild traumatic brain injury (mTBI) affects about 42 million people worldwide. It is often associated with headache, cognitive deficits and balance difficulties but rarely shows any abnormalities on conventional CT or MR imaging. While in most mTBI patients the symptoms resolve within 3 months, 10-15% of patients continue to exhibit symptoms beyond a year. Also, it is known that there exists a vulnerable period post-injury, when a second injury may exacerbate clinical prognosis. Identifying this vulnerable period may be critical for patient outcome, but very little is known about the neural underpinnings of mTBI and its recovery. In this work, we used advanced functional neuroimaging to study longitudinal changes in functional organization of the brain during the 3-month recovery period post mTBI. Fractional amplitude of low frequency fluctuations (fALFF) measured from resting state functional MRI (rs-fMRI) was found to be associated with symptom severity score (SSS, r=-0.28, p=0.002). Decreased fALFF was observed in specific functional networks for patients with higher SSS, and fALFF returned to higher values when the patient recovered (lower SSS). In addition, functional connectivity of the same networks was found to be associated with concurrent SSS, and connectivity immediately after injury (<10 days) was capable of predicting SSS at a later time point (3 weeks to 3 months, p<0.05). Specific networks including motor, default-mode and visual networks were found to be associated with SSS (p<0.001) , and connectivity between these networks predicted 3-month clinical outcome (motor and visual: p<0.001, default-mode: p<0.006). Our results suggest that functional connectivity in these networks are potential biomarkers for predicting mTBI recovery profiles and clinical outcome.

PMID: 30024343 [PubMed - as supplied by publisher]

Task-induced brain state manipulation improves prediction of individual traits.

Fri, 07/20/2018 - 11:20
Related Articles

Task-induced brain state manipulation improves prediction of individual traits.

Nat Commun. 2018 Jul 18;9(1):2807

Authors: Greene AS, Gao S, Scheinost D, Constable RT

Abstract
Recent work has begun to relate individual differences in brain functional organization to human behaviors and cognition, but the best brain state to reveal such relationships remains an open question. In two large, independent data sets, we here show that cognitive tasks amplify trait-relevant individual differences in patterns of functional connectivity, such that predictive models built from task fMRI data outperform models built from resting-state fMRI data. Further, certain tasks consistently yield better predictions of fluid intelligence than others, and the task that generates the best-performing models varies by sex. By considering task-induced brain state and sex, the best-performing model explains over 20% of the variance in fluid intelligence scores, as compared to <6% of variance explained by rest-based models. This suggests that identifying and inducing the right brain state in a given group can better reveal brain-behavior relationships, motivating a paradigm shift from rest- to task-based functional connectivity analyses.

PMID: 30022026 [PubMed - in process]

Intrinsic brain connectivity predicts impulse control disorders in patients with Parkinson's disease.

Fri, 07/20/2018 - 11:20
Related Articles

Intrinsic brain connectivity predicts impulse control disorders in patients with Parkinson's disease.

Mov Disord. 2017 Dec;32(12):1710-1719

Authors: Tessitore A, De Micco R, Giordano A, di Nardo F, Caiazzo G, Siciliano M, De Stefano M, Russo A, Esposito F, Tedeschi G

Abstract
BACKGROUND: Impulse control disorders can be triggered by dopamine replacement therapies in patients with PD. Using resting-state functional MRI, we investigated the intrinsic brain network connectivity at baseline in a cohort of drug-naive PD patients who successively developed impulse control disorders over a 36-month follow-up period compared with patients who did not.
METHODS: Baseline 3-Tesla MRI images of 30 drug-naive PD patients and 20 matched healthy controls were analyzed. The impulse control disorders' presence and severity at follow-up were assessed by the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease Rating Scale. Single-subject and group-level independent component analysis was used to investigate functional connectivity differences within the major resting-state networks. We also compared internetwork connectivity between patients. Finally, a multivariate Cox regression model was used to investigate baseline predictors of impulse control disorder development.
RESULTS: At baseline, decreased connectivity in the default-mode and right central executive networks and increased connectivity in the salience network were detected in PD patients with impulse control disorders at follow-up compared with those without. Increased default-mode/central executive internetwork connectivity was significantly associated with impulse control disorders development (P < 0.05).
CONCLUSIONS: Our findings demonstrated that abnormal brain connectivity in the three large-scale networks characterizes drug-naive PD patients who will eventually develop impulse control disorders while on dopaminergic treatment. We hypothesize that these divergent cognitive and limbic network connectivity changes could represent a potential biomarker and an additional risk factor for the emergence of impulse control disorders. © 2017 International Parkinson and Movement Disorder Society.

PMID: 28949049 [PubMed - indexed for MEDLINE]

Pre-surgical Brain Mapping: To Rest or Not to Rest?

Thu, 07/19/2018 - 10:20

Pre-surgical Brain Mapping: To Rest or Not to Rest?

Front Neurol. 2018;9:520

Authors: Rosazza C, Zacà D, Bruzzone MG

PMID: 30018589 [PubMed]

Altered Spontaneous Regional Brain Activity in the Insula and Visual Areas of Professional Traditional Chinese Pingju Opera Actors.

Thu, 07/19/2018 - 10:20

Altered Spontaneous Regional Brain Activity in the Insula and Visual Areas of Professional Traditional Chinese Pingju Opera Actors.

Front Neurosci. 2018;12:450

Authors: Zhang W, Zhao F, Qin W, Ma L

Abstract
Recent resting-state fMRI studies have revealed neuroplastic alterations after long-term training. However, the neuroplastic changes that occur in professional traditional Chinese Pingju opera actors remain unclear. Twenty professional traditional Chinese Pingju opera actors and 20 age-, sex-, and handedness-matched laymen were recruited. Resting-state fMRI was obtained by using an echo-planar imaging sequence, and two metrics, amplitude of low frequency fluctuation (ALFF) and regional homogeneity (ReHo), were utilized to assess spontaneous neural activity during resting state. Our results demonstrated that compared with laymen, professional traditional Chinese Pingju actors exhibited significantly decreased ALFF in the bilateral calcarine gyrus and cuneus; decreased ReHo in the bilateral superior occipital and calcarine gyri, cuneus, and right middle occipital gyrus; and increased ReHo in the left anterior insula. In addition, no significant association was found between spontaneous neural activity and Pingju opera training duration. Overall, the changes observed in spontaneous brain activity in professional traditional Chinese Pingju opera actors may indicate their superior performance of multidimensional professional skills, such as music and face perception, dancing, and emotional representation.

PMID: 30018534 [PubMed]

Shared endo-phenotypes of default mode dsfunction in attention deficit/hyperactivity disorder and autism spectrum disorder.

Thu, 07/19/2018 - 10:20

Shared endo-phenotypes of default mode dsfunction in attention deficit/hyperactivity disorder and autism spectrum disorder.

Transl Psychiatry. 2018 Jul 17;8(1):133

Authors: Kernbach JM, Satterthwaite TD, Bassett DS, Smallwood J, Margulies D, Krall S, Shaw P, Varoquaux G, Thirion B, Konrad K, Bzdok D

Abstract
Categorical diagnoses from the Diagnostic and Statistical Manual of Mental Disorders (DSM) or International Classification of Diseases (ICD) manuals are increasingly found to be incongruent with emerging neuroscientific evidence that points towards shared neurobiological dysfunction underlying attention deficit/hyperactivity disorder and autism spectrum disorder. Using resting-state functional magnetic resonance imaging data, functional connectivity of the default mode network, the dorsal attention and salience network was studied in 1305 typically developing and diagnosed participants. A transdiagnostic hierarchical Bayesian modeling framework combining Indian Buffet Processes and Latent Dirichlet Allocation was proposed to address the urgent need for objective brain-derived measures that can acknowledge shared brain network dysfunction in both disorders. We identified three main variation factors characterized by distinct coupling patterns of the temporoparietal cortices in the default mode network with the dorsal attention and salience network. The brain-derived factors were demonstrated to effectively capture the underlying neural dysfunction shared in both disorders more accurately, and to enable more reliable diagnoses of neurobiological dysfunction. The brain-derived phenotypes alone allowed for a classification accuracy reflecting an underlying neuropathology of 67.33% (+/-3.07) in new individuals, which significantly outperformed the 46.73% (+/-3.97) accuracy of categorical diagnoses. Our results provide initial evidence that shared neural dysfunction in ADHD and ASD can be derived from conventional brain recordings in a data-led fashion. Our work is encouraging to pursue a translational endeavor to find and further study brain-derived phenotypes, which could potentially be used to improve clinical decision-making and optimize treatment in the future.

PMID: 30018328 [PubMed - in process]

A Pilot Study Investigating a Novel Non-Linear Measure of Eyes Open versus Eyes Closed EEG Synchronization in People with Alzheimer's Disease and Healthy Controls.

Thu, 07/19/2018 - 10:20

A Pilot Study Investigating a Novel Non-Linear Measure of Eyes Open versus Eyes Closed EEG Synchronization in People with Alzheimer's Disease and Healthy Controls.

Brain Sci. 2018 Jul 17;8(7):

Authors: Blackburn DJ, Sarrigiannis PG, De Marco M, Zhao Y, Venneri A, Lawrence S, Unwin ZC, Blyth M, Angel J, Baster K, Wilkinson ID, Bell SM, He F, Wei HL, Billings SA, Farrow TFD

Abstract
BACKGROUND: The incidence of Alzheimer disease (AD) is increasing with the ageing population. The development of low cost non-invasive diagnostic aids for AD is a research priority. This pilot study investigated whether an approach based on a novel dynamic quantitative parametric EEG method could detect abnormalities in people with AD.
METHODS: 20 patients with probable AD, 20 matched healthy controls (HC) and 4 patients with probable fronto temporal dementia (FTD) were included. All had detailed neuropsychology along with structural, resting state fMRI and EEG. EEG data were analyzed using the Error Reduction Ratio-causality (ERR-causality) test that can capture both linear and nonlinear interactions between different EEG recording areas. The 95% confidence intervals of EEG levels of bi-centroparietal synchronization were estimated for eyes open (EO) and eyes closed (EC) states.
RESULTS: In the EC state, AD patients and HC had very similar levels of bi-centro parietal synchronization; but in the EO resting state, patients with AD had significantly higher levels of synchronization (AD = 0.44; interquartile range (IQR) 0.41 vs. HC = 0.15; IQR 0.17, p < 0.0001). The EO/EC synchronization ratio, a measure of the dynamic changes between the two states, also showed significant differences between these two groups (AD ratio 0.78 versus HC ratio 0.37 p < 0.0001). EO synchronization was also significantly different between AD and FTD (FTD = 0.075; IQR 0.03, p < 0.0001). However, the EO/EC ratio was not informative in the FTD group due to very low levels of synchronization in both states (EO and EC).
CONCLUSION: In this pilot work, resting state quantitative EEG shows significant differences between healthy controls and patients with AD. This approach has the potential to develop into a useful non-invasive and economical diagnostic aid in AD.

PMID: 30018264 [PubMed]

Multifocal epilepsy in children is associated with increased long-distance functional connectivity: An explorative EEG-fMRI study.

Thu, 07/19/2018 - 10:20

Multifocal epilepsy in children is associated with increased long-distance functional connectivity: An explorative EEG-fMRI study.

Eur J Paediatr Neurol. 2018 Jul 05;:

Authors: Siniatchkin M, Moehring J, Kroeher B, Galka A, von Ondarza G, Moeller F, Wolff S, Tagliazucchi E, Steinmann E, Boor R, Stephani U

Abstract
OBJECTIVE: Multifocal epileptic activity is an unfavourable feature of a number of epileptic syndromes (Lennox-Gastaut syndrome, West syndrome, severe focal epilepsies) which suggests an overall vulnerability of the brain to pathological synchronization. However, the mechanisms of multifocal activity are insufficiently understood. This explorative study investigates whether pathological connectivity within brain areas of the default mode network as well as thalamus, brainstem and retrosplenial cortex may predispose individuals to multifocal epileptic activity.
METHODS: 33 children suffering from multifocal and monofocal (control group) epilepsies were investigated using EEG-fMRI recordings during sleep. The blood oxygenated level dependent (BOLD) signal of 15 regions of interest was extracted and temporally correlated (resting-state functional connectivity).
RESULTS: Patients with monofocal epilepsies were characterized by strong correlations between the corresponding interhemispheric homotopic regions. This pattern of correlations with pronounced short-distance and weak long-distance functional connectivity resembles the connectivity pattern described for healthy children. Patients with multifocal epileptic activity, however, demonstrated significantly stronger correlations between a large number of regions of the default mode network as well as thalamus and brainstem, with a significant increase in long-distance connectivity compared to children with monofocal epileptic activity. In the group of patients with multifocal epilepsies there were no differences in functional connectivity between patients with or without Lennox-Gastaut syndrome.
CONCLUSION: This explorative study shows that multifocal activity is associated with generally increased long-distance functional connectivity in the brain. It can be suggested that this pronounced connectivity may represent either a risk to pathological over-synchronization or a consequence of the multifocal epileptic activity.

PMID: 30017619 [PubMed - as supplied by publisher]

Does brain functional connectivity contribute to musculoskeletal injury? A preliminary prospective analysis of a neural biomarker of ACL injury risk.

Thu, 07/19/2018 - 10:20

Does brain functional connectivity contribute to musculoskeletal injury? A preliminary prospective analysis of a neural biomarker of ACL injury risk.

J Sci Med Sport. 2018 Jul 10;:

Authors: Diekfuss JA, Grooms DR, Yuan W, Dudley J, Barber Foss KD, Thomas S, Ellis JD, Schneider DK, Leach J, Bonnette S, Myer GD

Abstract
OBJECTIVES: We aimed to present a unique prospective neurological dataset for participants who experienced an ACL injury.
DESIGN: Prospective longitudinal case-control.
METHODS: High school female soccer athletes were evaluated using functional magnetic resonance imaging to capture resting-state brain connectivity prior to their competitive season. Two of these athletes later experienced an ACL injury (ACLI). We matched these ACLI participants with eight teammates who did not go on to sustain an ACL injury (uninjured controls, Con) based on age, grade, sex, height, and weight to examine differences in preseason connectivity. Knee-motor regions of interest (ROIs) were created based on previously published data from which five specific areas were selected as seeds for analysis. Independent-samples t-tests with a false discovery rate correction for multiple comparisons determined differences in connectivity between the ACLI and Con.
RESULTS: There was significantly greater connectivity between the left primary sensory cortex (a brain region responsible for proprioception) and the right posterior lobe of the cerebellum (a brain region responsible for balance and coordination) for the Con relative to ACLI, t (8)=4.53, p=0.03 (false discovery rate corrected).
CONCLUSIONS: These preliminary data indicate that those who do not later sustain an ACL injury exhibit a stronger functional connection between a cortical sensory-motor region and a cerebellar region responsible for balance and coordination. These findings may help to guide development of brain-driven biofeedback training that optimizes and promotes adaptive neuroplasticity to reduce motor coordination errors and injury risk.

PMID: 30017465 [PubMed - as supplied by publisher]

Decreased functional connectivity within the default-mode network in acute brainstem ischemic stroke.

Thu, 07/19/2018 - 10:20

Decreased functional connectivity within the default-mode network in acute brainstem ischemic stroke.

Eur J Radiol. 2018 Aug;105:221-226

Authors: Jiang L, Geng W, Chen H, Zhang H, Bo F, Mao CN, Chen YC, Yin X

Abstract
PURPOSE: Ischemic stroke within the brainstem is associated with an increased risk of cognitive dysfunction. This study aimed to explore the integrity of a default-mode network (DMN) and its relationship with clinical variables in patients with acute ischemic brainstem stroke using an independent component analysis (ICA) approach.
MATERIALS AND METHODS: Twenty-one patients with acute ischemic brainstem stroke and 25 well-matched healthy subjects were enrolled in this study and underwent resting-state functional magnetic resonance imaging. The ICA was adopted to extract the DMN, including its anterior and posterior components. Pearson correlation analyses were performed to investigate the relationship between DMN connectivity and clinical variables.
RESULTS: Compared with healthy controls, patients with acute ischemic stroke showed significantly decreased functional connectivity in the right medial prefrontal cortex (mPFC) and right precuneus within the anterior and posterior DMN, respectively. After correcting for age, sex, and education, hypoconnectivity in the right mPFC and right precuneus was negatively correlated with higher homocysteine in patients with stroke (r = -0.592, p = 0.010 and r = -0.491, p = 0.039, respectively).
CONCLUSION: The finding of decreased functional connectivity within the DMN of patients with acute brainstem stroke provides novel insight into the neural mechanisms that underlie cognitive impairment following ischemic insult to this brain region.

PMID: 30017284 [PubMed - in process]

Pages