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Creative music therapy to promote brain function and brain structure in preterm infants: A randomized controlled pilot study.

Fri, 01/24/2020 - 23:01
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Creative music therapy to promote brain function and brain structure in preterm infants: A randomized controlled pilot study.

Neuroimage Clin. 2020 Jan 13;25:102171

Authors: Haslbeck FB, Jakab A, Held U, Bassler D, Bucher HU, Hagmann C

Abstract
Cognitive and neurobehavioral problems are among the most severe adverse outcomes in very preterm infants. Such neurodevelopmental impairments may be mitigated through nonpharmacological interventions such as creative music therapy (CMT), an interactive, resource- and needs-oriented approach that provides individual social contact and musical stimulation. The aim was to test the feasibility of a study investigating the role of CMT and to measure the short- and medium-term effects of CMT on structural and functional brain connectivity with MRI. In this randomized, controlled clinical pilot feasibility trial, 82 infants were randomized to either CMT or standard care. A specially trained music therapist provided CMT via infant-directed humming and singing in lullaby style. To test the short-term effects of CMT on brain structure and function, diffusion tensor imaging data and resting-state functional imaging data were acquired. Clinical feasibility was achieved despite moderate parental refusal mainly in the control group after randomization. 40 infants remained as final cohort for the MRI analysis. Structural brain connectivity appears to be moderately affected by CMT, structural connectomic analysis revealed increased integration in the posterior cingulate cortex only. Lagged resting-state MRI analysis showed lower thalamocortical processing delay, stronger functional networks, and higher functional integration in predominantly left prefrontal, supplementary motor, and inferior temporal brain regions in infants treated with CMT. This trial provides unique evidence that CMT has beneficial effects on functional brain activity and connectivity in networks underlying higher-order cognitive, socio-emotional, and motor functions in preterm infants. Our results indicate the potential of CMT to improve long-term neurodevelopmental outcomes in children born very preterm.

PMID: 31972397 [PubMed - as supplied by publisher]

The functional implications and modifiability of resting-state brain network complexity in older adults.

Fri, 01/24/2020 - 23:01
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The functional implications and modifiability of resting-state brain network complexity in older adults.

Neurosci Lett. 2020 Jan 20;:134775

Authors: Zhou J, Lo OY, Halko MA, Harrison R, Lipsitz LA, Manor B

Abstract
The dynamics of the resting-state activity in brain functional networks are complex, containing meaningful patterns over multiple temporal scales. Such physiologic complexity is often diminished in older adults. Here we aim to examine if the resting-state complexity within functional brain networks is sensitive to functional status in older adults and if repeated exposure to transcranial direct current stimulation (tDCS) would modulate such complexity. Twelve older adults with slow gait and mild-to-moderate executive dysfunction and 12 age- and sex-matched controls completed a baseline resting-state fMRI (rs-fMRI). Ten participants in the functionally-limited group then completed ten 20-minute sessions of real (n = 6) or sham (n = 4) tDCS targeting the left prefrontal cortex over a two-week period as well as a follow-up rs-fMRI. The resting-state complexity associated with seven functional networks was quantified by averaging the multiscale entropy (MSE) of the blood oxygen level-dependent (BOLD) time-series for all voxels within each network. Compared to controls, functionally-limited group exhibited lower complexity in the motor, ventral attention, limbic, executive and default mode networks (F > 6.3, p < 0.02). Within this group, those who received tDCS exhibited greater complexity within the ventral, executive and limbic networks (p < 0.04) post intervention as compared to baseline, while no significant changes in sham group was observed. This study provides preliminary evidence that older adults with functional limitations had diminished complexity of resting-state brain network activity and repeated exposure to tDCS may increase that resting-state complexity, warranting future studies to establish such complexity as a marker of brain health in older adults.

PMID: 31972253 [PubMed - as supplied by publisher]

Behavioral deficits in left hemispatial neglect are related to a reduction of spontaneous neuronal activity in the right superior parietal lobule.

Fri, 01/24/2020 - 23:01
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Behavioral deficits in left hemispatial neglect are related to a reduction of spontaneous neuronal activity in the right superior parietal lobule.

Neuropsychologia. 2020 Jan 20;:107356

Authors: Machner B, von der Gablentz J, Göttlich M, Heide W, Helmchen C, Sprenger A, Münte TF

Abstract
Focal brain lesions may induce dysfunctions in distant brain regions leading to behavioral impairments. Based on this concept of 'diaschisis', spatial neglect following stroke has been related to structural damage of the right-lateralized ventral attention network (VAN) and disrupted inter-hemispheric functional connectivity (FC) in the bilateral dorsal attention network (DAN). We questioned whether neglect-related behavioral deficits may be determined by local dysfunction of a specific region within these brain networks. We investigated acute right-hemisphere stroke patients with left hemispatial neglect using resting-state functional MRI, neuropsychological tests of spatial attention and clinical assessment of neglect-related functional disability. In addition to conventional FC analyses between different cortical regions of interest (ROIs) in the DAN/VAN, we extracted the fractional amplitude of low frequency fluctuations (fALFF) from each ROI as a marker of regional spontaneous neuronal activity. Although DAN regions (as opposed to the VAN regions) were largely spared from structural brain damage, they exhibited a significant reduction of inter-hemispheric FC. However, significant fMRI-behavior correlations were revealed specifically for the fALFF of one DAN-ROI in the right superior parietal lobule (SPL): the smaller the fALFF in the right posterior intraparietal sulcus, the more severe the patient's pathological attention bias and neglect-related functional impairment. In line with 'diaschisis', our findings confirm a crucial role of the non-lesioned but dysfunctional right SPL for the emergence of spatial neglect and its behavioral consequences. They further support targeting the SPL dysfunction by non-invasive brain stimulation in neglect rehabilitation.

PMID: 31972231 [PubMed - as supplied by publisher]

Modulation of Distinct Intrinsic Resting State Brain Networks by Acute Exercise Bouts of Differing Intensity.

Fri, 01/24/2020 - 23:01
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Modulation of Distinct Intrinsic Resting State Brain Networks by Acute Exercise Bouts of Differing Intensity.

Brain Plast. 2019 Dec 26;5(1):39-55

Authors: Schmitt A, Upadhyay N, Martin JA, Rojas S, Strüder HK, Boecker H

Abstract
Acute exercise bouts alter resting state functional connectivity (rs-FC) within cognitive, sensorimotor, and affective networks, but it remains unknown how these effects are influenced by exercise intensity. Twenty-five male athletes underwent individual fitness assessments using an incremental treadmill test. On separate days, they performed 'low' (35% below lactate threshold) and 'high' (20% above lactate threshold) intensity exercise bouts of 30 min. Rs-fMRI and Positive and Negative Affect Scale (PANAS) were acquired before and after each exercise bout. Networks of interest were extracted from twenty-two participants (3 dropouts). Pre-to-post changes and between conditions effects were evaluated using FSL's randomise by applying repeated measures ANOVA. Results were reported at p < 0.05, corrected for multiple comparisons using threshold free cluster enhancement. PANAS revealed a significant increase in positive mood after both exercise conditions. Significant effects were observed between conditions in the right affective and reward network (ARN), the right fronto parietal network (FPN) and the sensorimotor network (SMN). Pre-to-post comparisons after 'low' exercise intensity revealed a significant increase in rs-FC in the left and right FPN, while after 'high'-intensity exercise rs-FC decreased in the SMN and the dorsal attention network (DAN) and increased in the left ARN. Supporting recent findings, this study is the first to report distinct rs-FC alterations driven by exercise intensity: (i) Increased rs-FC in FPN may indicate beneficial functional plasticity for cognitive/attentional processing, (ii) increased rs-FC in ARN may be linked to endogenous opioid-mediated internal affective states. Finally, (iii) decreased rs-FC in the SMN may signify persistent motor fatigue. The distinct effects on rs-FC fit with theories of transient persistent network alterations after acute exercise bouts that are mediated by different exercise intensities and impact differentially on cognitive/attentional or affective responses.

PMID: 31970059 [PubMed]

Current Challenges in Translational and Clinical fMRI and Future Directions.

Fri, 01/24/2020 - 23:01
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Current Challenges in Translational and Clinical fMRI and Future Directions.

Front Psychiatry. 2019;10:924

Authors: Specht K

Abstract
Translational neuroscience is an important field that brings together clinical praxis with neuroscience methods. In this review article, the focus will be on functional neuroimaging (fMRI) and its applicability in clinical fMRI studies. In the light of the "replication crisis," three aspects will be critically discussed: First, the fMRI signal itself, second, current fMRI praxis, and, third, the next generation of analysis strategies. Current attempts such as resting-state fMRI, meta-analyses, and machine learning will be discussed with their advantages and potential pitfalls and disadvantages. One major concern is that the fMRI signal shows substantial within- and between-subject variability, which affects the reliability of both task-related, but in particularly resting-state fMRI studies. Furthermore, the lack of standardized acquisition and analysis methods hinders the further development of clinical relevant approaches. However, meta-analyses and machine-learning approaches may help to overcome current shortcomings in the methods by identifying new, and yet hidden relationships, and may help to build new models on disorder mechanisms. Furthermore, better control of parameters that may have an influence on the fMRI signal and that can easily be controlled for, like blood pressure, heart rate, diet, time of day, might improve reliability substantially.

PMID: 31969840 [PubMed]

Continuous reorganization of cortical information flow in multiple sclerosis: A longitudinal fMRI effective connectivity study.

Thu, 01/23/2020 - 20:00
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Continuous reorganization of cortical information flow in multiple sclerosis: A longitudinal fMRI effective connectivity study.

Sci Rep. 2020 Jan 21;10(1):806

Authors: Fleischer V, Muthuraman M, Anwar AR, Gonzalez-Escamilla G, Radetz A, Gracien RM, Bittner S, Luessi F, Meuth SG, Zipp F, Groppa S

Abstract
Effective connectivity (EC) is able to explore causal effects between brain areas and can depict mechanisms that underlie repair and adaptation in chronic brain diseases. Thus, the application of EC techniques in multiple sclerosis (MS) has the potential to determine directionality of neuronal interactions and may provide an imaging biomarker for disease progression. Here, serial longitudinal structural and resting-state fMRI was performed at 12-week intervals over one year in twelve MS patients. Twelve healthy subjects served as controls (HC). Two approaches for EC quantification were used: Causal Bayesian Network (CBN) and Time-resolved Partial Directed Coherence (TPDC). The EC strength was correlated with the Expanded Disability Status Scale (EDSS) and Fatigue Scale for Motor and Cognitive functions (FSMC). Our findings demonstrated a longitudinal increase in EC between specific brain regions, detected in both the CBN and TPDC analysis in MS patients. In particular, EC from the deep grey matter, frontal, prefrontal and temporal regions showed a continuous increase over the study period. No longitudinal changes in EC were attested in HC during the study. Furthermore, we observed an association between clinical performance and EC strength. In particular, the EC increase in fronto-cerebellar connections showed an inverse correlation with the EDSS and FSMC. Our data depict continuous functional reorganization between specific brain regions indicated by increasing EC over time in MS, which is not detectable in HC. In particular, fronto-cerebellar connections, which were closely related to clinical performance, may provide a marker of brain plasticity and functional reserve in MS.

PMID: 31964982 [PubMed - in process]

An fMRI-based neural marker for migraine without aura.

Thu, 01/23/2020 - 20:00
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An fMRI-based neural marker for migraine without aura.

Neurology. 2020 Jan 21;:

Authors: Tu Y, Zeng F, Lan L, Li Z, Maleki N, Liu B, Chen J, Wang C, Park J, Lang C, Yujie G, Liu M, Fu Z, Zhang Z, Liang F, Kong J

Abstract
OBJECTIVE: To identify and validate an fMRI-based neural marker for migraine without aura (MwoA) and to examine its association with treatment response.
METHODS: We conducted cross-sectional studies with resting-state fMRI data from 230 participants and machine learning analyses. In studies 1 through 3, we identified, cross-validated, independently validated, and cross-sectionally validated an fMRI-based neural marker for MwoA. In study 4, we assessed the relationship between the neural marker and treatment responses in migraineurs who received a 4-week real or sham acupuncture treatment, or were waitlisted, in a registered clinical trial.
RESULTS: In study 1 (n = 116), we identified a neural marker with abnormal functional connectivity within the visual, default mode, sensorimotor, and frontal-parietal networks that could discriminate migraineurs from healthy controls (HCs) with 93% sensitivity and 89% specificity. In study 2 (n = 38), we investigated the generalizability of the marker by applying it to an independent cohort of migraineurs and HCs and achieved 84% sensitivity and specificity. In study 3 (n = 76), we verified the specificity of the marker with new datasets of migraineurs and patients with other chronic pain disorders (chronic low back pain and fibromyalgia) and demonstrated 78% sensitivity and 76% specificity for discriminating migraineurs from nonmigraineurs. In study 4 (n = 116), we found that the changes in the marker responses showed significant correlation with the changes in headache frequency in response to real acupuncture.
CONCLUSION: We identified an fMRI-based neural marker that captures distinct characteristics of MwoA and can link disease pattern changes to brain changes.

PMID: 31964691 [PubMed - as supplied by publisher]

Human brain functional network organization is disrupted following whole-brain radiation therapy.

Thu, 01/23/2020 - 20:00
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Human brain functional network organization is disrupted following whole-brain radiation therapy.

Brain Connect. 2020 Jan 22;:

Authors: Mitchell T, Seitzman B, Ballard N, Petersen SE, Shimony J, Leuthardt E

Abstract
Radiation therapy plays a vital role in the treatment of brain cancers, but frequently results in cognitive decline in the patients who receive it. Because the underlying mechanisms for this decline remains poorly understood, the brain is typically treated as a single, uniform volume when evaluating the toxic effects of radiation therapy plans. This ignorance represents a significant deficit in the field of radiation oncology, as the technology exists to manipulate dose distributions to spare regions of the brain, but there exists no body of knowledge regarding what is critical to spare. This deficit exists due to the numerous confounding factors that are frequently associated with radiotherapy, including the tumors themselves, other treatments such as surgery and chemotherapy, and dose gradients across the brain. Here, we present a case in which a 57 year-old male patient received a uniform dose of radiation across the whole brain, did not receive concurrent chemotherapy, had minimal surgical intervention and a small tumor burden, and received resting-state functional MRI scans before and after radiation therapy. To our knowledge, this is the first study on the effects of whole brain radiotherapy on functional network organization, and this patient's treatment regimen represents a rare and non-replicable opportunity to isolate the effects of radiation on functional connectivity. We observed substantial changes in the subject's behavior and functional network organization over a 12-month timeframe. Interestingly, the homogenous radiation dose to the brain had a heterogeneous effect on cortical networks, and the functional networks most affected correspond with observed cognitive behavioral deficits. This novel study suggests that the cognitive decline that occurs after whole-brain radiation therapy may be network specific and related to the disruption of large-scale distributed functional systems, and indicates that functional MRI is a promising avenue of study for optimizing cognitive outcomes following radiation therapy.

PMID: 31964163 [PubMed - as supplied by publisher]

Characterizing intrinsic functional connectivity in relation to impaired self-regulation in intellectually able male youth with autism spectrum disorder.

Wed, 01/22/2020 - 22:58
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Characterizing intrinsic functional connectivity in relation to impaired self-regulation in intellectually able male youth with autism spectrum disorder.

Autism. 2020 Jan 21;:1362361319888104

Authors: Lin HY, Ni HC, Tseng WI, Gau SS

Abstract
LAY ABSTRACT: Impaired self-regulation (i.e., dysregulation in affective, behavioral, and cognitive control), is commonly present in young people with autism spectrum disorder (ASD). However, little is known about what is happening in people's brains when self-regulation is impaired in young people with ASD. We used a technique called functional MRI (which measures brain activity by detecting changes associated with blood flow) at a resting state (when participants are not asked to do anything) to research this in intellectually able young people with ASD. We found that brains with more connections, especially between regions involved in sensorimotor processing and regions involved in the processes that enable peoples to focus their attention on the most pertinent features from the sensory environment (salience processing), were related to more impaired self-regulation in young people with and without ASD. We also found that impaired self-regulation was related to increased communication within the brain system involved in voluntary orienting attention to a sensory cue (the dorsal attention network) in young people with ASD. These results highlight how different people have different degrees of dysregulation, which has been largely overlooked in the earlier brain imaging reports on ASD. This might contribute to understanding some of the inconsistencies in the existing published literature on this topic.

PMID: 31958997 [PubMed - as supplied by publisher]

A 7 Tesla fMRI investigation of human tinnitus percept in cortical and subcortical auditory areas.

Tue, 01/21/2020 - 22:56
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A 7 Tesla fMRI investigation of human tinnitus percept in cortical and subcortical auditory areas.

Neuroimage Clin. 2020 Jan 11;25:102166

Authors: Berlot E, Arts R, Smit J, George E, Gulban OF, Moerel M, Stokroos R, Formisano E, De Martino F

Abstract
Tinnitus is a clinical condition defined by hearing a sound in the absence of an objective source. Early experiments in animal models have suggested that tinnitus stems from an alteration of processing in the auditory system. However, translating these results to humans has proven challenging. One limiting factor has been the insufficient spatial resolution of non-invasive measurement techniques to investigate responses in subcortical auditory nuclei, like the inferior colliculus and the medial geniculate body (MGB). Here we employed ultra-high field functional magnetic resonance imaging (UHF-fMRI) at 7 Tesla to investigate the frequency-specific processing in sub-cortical and cortical regions in a cohort of six tinnitus patients and six hearing loss matched controls. We used task-based fMRI to perform tonotopic mapping and compared the magnitude and tuning of frequency-specific responses between the two groups. Additionally, we used resting-state fMRI to investigate the functional connectivity. Our results indicate frequency-unspecific reductions in the selectivity of frequency tuning that start at the level of the MGB and continue in the auditory cortex, as well as reduced thalamocortical and cortico-cortical connectivity with tinnitus. These findings suggest that tinnitus may be associated with reduced inhibition in the auditory pathway, potentially leading to increased neural noise and reduced functional connectivity. Moreover, these results indicate the relevance of high spatial resolution UHF-fMRI for the investigation of the role of sub-cortical auditory regions in tinnitus.

PMID: 31958686 [PubMed - as supplied by publisher]

Cortical laminar resting-state signal fluctuations scale with the hypercapnic blood oxygenation level-dependent response.

Tue, 01/21/2020 - 22:56
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Cortical laminar resting-state signal fluctuations scale with the hypercapnic blood oxygenation level-dependent response.

Hum Brain Mapp. 2020 Jan 20;:

Authors: Guidi M, Huber L, Lampe L, Merola A, Ihle K, Möller HE

Abstract
Calibrated functional magnetic resonance imaging can remove unwanted sources of signal variability in the blood oxygenation level-dependent (BOLD) response. This is achieved by scaling, using information from a perfusion-sensitive scan during a purely vascular challenge, typically induced by a gas manipulation or a breath-hold task. In this work, we seek for a validation of the use of the resting-state fluctuation amplitude (RSFA) as a scaling factor to remove vascular contributions from the BOLD response. Given the peculiarity of depth-dependent vascularization in gray matter, BOLD and vascular space occupancy (VASO) data were acquired at submillimeter resolution and averaged across cortical laminae. RSFA from the primary motor cortex was, thus, compared to the amplitude of hypercapnia-induced signal changes (tSDhc ) and with the M factor of the Davis model on a laminar level. High linear correlations were observed for RSFA and tSDhc ( R2 = 0.92 ± 0.06) and somewhat reduced for RSFA and M ( R2 = 0.62 ± 0.19). Laminar profiles of RSFA-normalized BOLD signal changes yielded good agreement with corresponding VASO profiles. Overall, this suggests that RSFA contains strong vascular components and is also modulated by baseline quantities contained in the M factor. We conclude that RSFA may replace the scaling factor tSDhc for normalizing the laminar BOLD response.

PMID: 31957959 [PubMed - as supplied by publisher]

Corrigendum: Resting-State Brain Signal Variability in Prefrontal Cortex Is Associated With ADHD Symptom Severity in Children.

Tue, 01/21/2020 - 22:56
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Corrigendum: Resting-State Brain Signal Variability in Prefrontal Cortex Is Associated With ADHD Symptom Severity in Children.

Front Hum Neurosci. 2019;13:431

Authors: Nomi JS, Schettini E, Voorhies W, Bolt TS, Heller AS, Uddin LQ

Abstract
[This corrects the article on p. 90 in vol. 12, PMID: 29593515.].

PMID: 31956303 [PubMed - in process]

Targeted Stimulation of Human Orbitofrontal Networks Disrupts Outcome-Guided Behavior.

Tue, 01/21/2020 - 22:56
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Targeted Stimulation of Human Orbitofrontal Networks Disrupts Outcome-Guided Behavior.

Curr Biol. 2020 Jan 07;:

Authors: Howard JD, Reynolds R, Smith DE, Voss JL, Schoenbaum G, Kahnt T

Abstract
Outcome-guided behavior requires knowledge about the current value of expected outcomes. Such behavior can be isolated in the reinforcer devaluation task, which assesses the ability to infer the current value of specific rewards after devaluation. Animal lesion studies demonstrate that orbitofrontal cortex (OFC) is necessary for normal behavior in this task, but a causal role for human OFC in outcome-guided behavior has not been established. Here, we used sham-controlled, non-invasive, continuous theta-burst stimulation (cTBS) to temporarily disrupt human OFC network activity by stimulating a site in the lateral prefrontal cortex that is strongly connected to OFC prior to devaluation of food odor rewards. Subjects in the sham group appropriately avoided Pavlovian cues associated with devalued food odors. However, subjects in the stimulation group persistently chose those cues, even though devaluation of food odors themselves was unaffected by cTBS. This behavioral impairment was mirrored in changes in resting-state functional magnetic resonance imaging (rs-fMRI) activity such that subjects in the stimulation group exhibited reduced OFC network connectivity after cTBS, and the magnitude of this reduction was correlated with choices after devaluation. These findings demonstrate the feasibility of indirectly targeting the human OFC with non-invasive cTBS and indicate that OFC is specifically required for inferring the value of expected outcomes.

PMID: 31956033 [PubMed - as supplied by publisher]

Reorganized functional connectivity of language centers as a possible compensatory mechanism for basal ganglia aphasia.

Tue, 01/21/2020 - 22:56
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Reorganized functional connectivity of language centers as a possible compensatory mechanism for basal ganglia aphasia.

Brain Inj. 2020 Jan 20;:1-8

Authors: Xu L, Huang L, Cui W, Yu Q

Abstract
Primary Object: To investigate the functional connectivity (FC) of cortical language centers in patients who have regained fluent speech after basal ganglia aphasia and identify the possible compensatory mechanism.Methods & Procedures: A retrospective cohort of 12 patients and 17 healthy controls were studied using resting-state functional MRI (rs-fMRI). All patients suffered from an ischemic stroke with lesions confined to the basal ganglia and showed impaired language functions at admission. Seven patients had lesions in the left basal ganglia, three in the right, and two in both sides. The rs-fMRI was performed after the patients regained fluent speech. Broca's area, Wernicke's area, and their contralateral homologues were selected as the region-of-interest (ROI) for both voxel-wise and ROI-wise FC studies.Results: We discovered that the interhemispheric FC of the language centers (i.e. Broca's area and Wernicke's area) decreased and the intrahemispheric FC of the language centers increased in these patients who regained fluent speech after basal ganglia aphasia.Conclusions: We speculated that damages to the basal ganglia disrupted the cortico-subcortical circuits that facilitated the transhemispheric communications of language functions, resulting in decreased interhemispheric FC. Consequently, the intrahemispheric FC increased as a possible compensatory mechanism to restore the language functions.

PMID: 31955634 [PubMed - as supplied by publisher]

Oxytocin effects on the resting-state mentalizing brain network.

Mon, 01/20/2020 - 19:55

Oxytocin effects on the resting-state mentalizing brain network.

Brain Imaging Behav. 2020 Jan 18;:

Authors: Wu H, Feng C, Lu X, Liu X, Liu Q

Abstract
Oxytocin (OT) has modulatory effects in both human behavior and in the brain, which is not limited in the specific brain area but also with the potential effect on connectivity with other brain regions. Evidence indicates that OT effects on human behavior are multifaceted, such as trust behavior, decrease anxiety, empathy and bonding behavior. For the vital role of mentalizing in understanding others, here we examine whether OT has a general effect on mentalizing brain network which is associated to the effect of related social behavioral and personality traits. Using a randomized, double-blind placebo-controlled group design, we investigate the resting-state functional magnetic resonance imaging after intranasal OT or placebo. The functional connectivity (FC) maps with seed in left/right temporoparietal junction (lTPJ/rTPJ) showed that OT significantly increased connectivity between rTPJ and default attention network (DAN), but decreased the FC between lTPJ and medial prefrontal network (MPN). With machine learning approach, we report that identified altered FCs of TPJ can classify OT and placebo (PL) group. Moreover, individual's empathy trait can modulate the FC between left TPJ and right rectus (RECT), which shows a positive correlation with empathic concern in PL group but a negative correlation in OT group. These results demonstrate that OT has significant effect on FC with lTPJ and rTPJ, brain regions where are critical for mentalizing, and the empathy concern can modulate the FC. These findings advance our understanding of the neural mechanisms by which OT modulates social behaviors, especially in social interaction involving mentalizing.

PMID: 31955321 [PubMed - as supplied by publisher]

Abnormal degree centrality in delayed encephalopathy after carbon monoxide poisoning: a resting-state fMRI study.

Mon, 01/20/2020 - 19:55

Abnormal degree centrality in delayed encephalopathy after carbon monoxide poisoning: a resting-state fMRI study.

Neuroradiology. 2020 Jan 18;:

Authors: Wu K, Liu M, He L, Tan Y

Abstract
PURPOSE: To explore neuropathologic mechanisms in functional brain regions in patients with delayed encephalopathy after carbon monoxide poisoning (DEACMP) from the perspective of the brain network nodes by resting-state functional magnetic resonance imaging (rs-fMRI).
METHODS: The fMRI and cognitive assessments were performed in 25 patients with DEACMP and 25 age-, sex- and education-matched healthy controls (HCs). Data analysis was performed via the degree centrality (DC) method. Then, the associations between the cognitive assessments and DC in the identified abnormal brain regions were assessed by using a correlation analysis.
RESULTS: Compared with the HCs, the DEACMP patients displayed significantly decreased DC values in the right superior frontal gyrus, right precentral gyrus, right angular gyrus, right marginal gyrus, right hippocampus, and left thalamus but increased DC values in the right inferior frontal gyrus, right cingulate gyrus, left superior temporal gyrus, left medial temporal gyrus, right lingual gyrus, and right posterior cerebellar lobe, pons, and midbrain (GRF correction, voxel P value < 0.001, cluster P value < 0.01). The correlation analysis in the DEACMP group revealed that there was a negative correlation between the DC values in the right hippocampus and MMSE scores, whereas a positive correlation was observed in the right cingulate gyrus.
CONCLUSIONS: Patients with DEACMP exhibited abnormal degree centrality in the brain network. This finding may provide a new approach for examining the neuropathologic mechanisms underlying DEACMP.

PMID: 31955235 [PubMed - as supplied by publisher]

Aberrant resting-state interhemispheric functional connectivity in patients with postpartum depression.

Mon, 01/20/2020 - 19:55

Aberrant resting-state interhemispheric functional connectivity in patients with postpartum depression.

Behav Brain Res. 2020 Jan 16;:112483

Authors: Zhang S, Wang W, Wang G, Li B, Chai L, Guo J, Gao X

Abstract
The aim of this study is to investigate the alterations of interhemispheric functional connectivity in patients with postpartum depression (PPD) during resting state, and their potential correlations with clinical severity. Twenty- eight patients with PPD and twenty-five matched healthy postpartum (HP) women within 4 weeks after delivery were recruited and performed resting-state functional magnetic resonance imaging(fMRI) scans. Voxel-mirrored homotopic connectivity (VMHC), which is useful for exploring interhemispheric functional connectivity, and has been widely utilized to identify abnormal functional connectivity between the symmetrical brain regions in many diseases, was calculated in the present study, and intergroup VMHC differences in the voxel manner were analyzed. Correlations between VMHC values and clinical variables were also analyzed. Compared with HP, patients with PPD exhibited significantly decreased VMHC values in bilateral dorsomedial prefrontal cortex (dmPFC), dorsal anterior cingulate cortex (dACC) and orbitofrontal cortex (OFC). Furthermore, VMHC values within the dmPFC negatively correlated with the Edinburgh postpartum depression scale (EPDS) score. These findings suggested that functional coordination between several homotopic brain regions were impaired in patients with PPD. This study provided evidences of aberrant interhemispheric connectivity within brain regions involved in the maternal care network in PPD, and may contribute to the further understanding of the neural mechanism underlying PPD.

PMID: 31954737 [PubMed - as supplied by publisher]

Functional brain architecture is associated with the rate of tau accumulation in Alzheimer's disease.

Sun, 01/19/2020 - 19:53
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Functional brain architecture is associated with the rate of tau accumulation in Alzheimer's disease.

Nat Commun. 2020 Jan 17;11(1):347

Authors: Franzmeier N, Neitzel J, Rubinski A, Smith R, Strandberg O, Ossenkoppele R, Hansson O, Ewers M, Alzheimer’s Disease Neuroimaging Initiative (ADNI)

Abstract
In Alzheimer's diseases (AD), tau pathology is strongly associated with cognitive decline. Preclinical evidence suggests that tau spreads across connected neurons in an activity-dependent manner. Supporting this, cross-sectional AD studies show that tau deposition patterns resemble functional brain networks. However, whether higher functional connectivity is associated with higher rates of tau accumulation is unclear. Here, we combine resting-state fMRI with longitudinal tau-PET in two independent samples including 53 (ADNI) and 41 (BioFINDER) amyloid-biomarker defined AD subjects and 28 (ADNI) vs. 16 (BioFINDER) amyloid-negative healthy controls. In both samples, AD subjects show faster tau accumulation than controls. Second, in AD, higher fMRI-assessed connectivity between 400 regions of interest (ROIs) is associated with correlated tau-PET accumulation in corresponding ROIs. Third, we show that a model including baseline connectivity and tau-PET is associated with future tau-PET accumulation. Together, connectivity is associated with tau spread in AD, supporting the view of transneuronal tau propagation.

PMID: 31953405 [PubMed - in process]

Altered resting-state dynamic functional brain networks in major depressive disorder: Findings from the REST-meta-MDD consortium.

Sun, 01/19/2020 - 19:53
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Altered resting-state dynamic functional brain networks in major depressive disorder: Findings from the REST-meta-MDD consortium.

Neuroimage Clin. 2020 Jan 07;:102163

Authors: Long Y, Cao H, Yan C, Chen X, Li L, Castellanos FX, Bai T, Bo Q, Chen G, Chen N, Chen W, Cheng C, Cheng Y, Cui X, Duan J, Fang Y, Gong Q, Guo W, Hou Z, Hu L, Kuang L, Li F, Li K, Li T, Liu Y, Luo Q, Meng H, Peng D, Qiu H, Qiu J, Shen Y, Shi Y, Si T, Wang C, Wang F, Wang K, Wang L, Wang X, Wang Y, Wu X, Wu X, Xie C, Xie G, Xie H, Xie P, Xu X, Yang H, Yang J, Yao J, Yao S, Yin Y, Yuan Y, Zhang A, Zhang H, Zhang K, Zhang L, Zhang Z, Zhou R, Zhou Y, Zhu J, Zou C, Zang Y, Zhao J, Kin-Yuen Chan C, Pu W, Liu Z

Abstract
BACKGROUND: Major depressive disorder (MDD) is known to be characterized by altered brain functional connectivity (FC) patterns. However, whether and how the features of dynamic FC would change in patients with MDD are unclear. In this study, we aimed to characterize dynamic FC in MDD using a large multi-site sample and a novel dynamic network-based approach.
METHODS: Resting-state functional magnetic resonance imaging (fMRI) data were acquired from a total of 460 MDD patients and 473 healthy controls, as a part of the REST-meta-MDD consortium. Resting-state dynamic functional brain networks were constructed for each subject by a sliding-window approach. Multiple spatio-temporal features of dynamic brain networks, including temporal variability, temporal clustering and temporal efficiency, were then compared between patients and healthy subjects at both global and local levels.
RESULTS: The group of MDD patients showed significantly higher temporal variability, lower temporal correlation coefficient (indicating decreased temporal clustering) and shorter characteristic temporal path length (indicating increased temporal efficiency) compared with healthy controls (corrected p < 3.14×10-3). Corresponding local changes in MDD were mainly found in the default-mode, sensorimotor and subcortical areas. Measures of temporal variability and characteristic temporal path length were significantly correlated with depression severity in patients (corrected p < 0.05). Moreover, the observed between-group differences were robustly present in both first-episode, drug-naïve (FEDN) and non-FEDN patients.
CONCLUSIONS: Our findings suggest that excessive temporal variations of brain FC, reflecting abnormal communications between large-scale bran networks over time, may underlie the neuropathology of MDD.

PMID: 31953148 [PubMed - as supplied by publisher]

Forced conceptual thought induced by electrical stimulation of the left prefrontal gyrus involves widespread neural networks.

Sat, 01/18/2020 - 19:52

Forced conceptual thought induced by electrical stimulation of the left prefrontal gyrus involves widespread neural networks.

Epilepsy Behav. 2020 Jan 14;104(Pt A):106644

Authors: Liu A, Friedman D, Barron DS, Wang X, Thesen T, Dugan P

Abstract
BACKGROUND: Early accounts of forced thought were reported at the onset of a focal seizure, and characterized as vague, repetitive, and involuntary intellectual auras distinct from perceptual or psychic hallucinations or illusions. Here, we examine the neural underpinnings involved in conceptual thought by presenting a series of 3 patients with epilepsy reporting intrusive thoughts during electrical stimulation of the left lateral prefrontal cortex (PFC) during invasive surgical evaluation. We illustrate the widespread networks involved through two independent brain imaging modalities: resting state functional magnetic resonance imaging (fMRI) (rs-fMRI) and task-based meta-analytic connectivity modeling (MACM).
METHODS: We report the clinical and stimulation characteristics of three patients with left hemispheric language dominance who demonstrate forced thought with functional mapping. To examine the brain networks underlying this phenomenon, we used the regions of interest (ROI) centered at the active electrode pairs. We modeled functional networks using two approaches: (1) rs-fMRI functional connectivity analysis, representing 81 healthy controls and (2) meta-analytic connectivity modeling (MACM), representing 8260 healthy subjects. We also determined the overlapping regions between these three subjects' rs-fMRI and MACM networks through a conjunction analysis.
RESULTS: We identified that left PFC was associated with a large-scale functional network including frontal, temporal, and parietal regions, a network that has been associated with multiple cognitive functions including semantics, speech, attention, working memory, and explicit memory.
CONCLUSIONS: We illustrate the neural networks involved in conceptual thought through a unique patient population and argue that PFC supports this function through activation of a widespread network.

PMID: 31951969 [PubMed - as supplied by publisher]