New resting-state fMRI related studies at PubMed

Altered resting-state functional connectivity of the dorsal anterior cingulate cortex with intrinsic brain networks in male problematic smartphone users

Thu, 10/20/2022 - 10:00

Front Psychiatry. 2022 Oct 3;13:1008557. doi: 10.3389/fpsyt.2022.1008557. eCollection 2022.


The excessive use of smartphones is associated with various medical complications and mental health problems. However, existing research findings on neurobiological mechanisms behind problematic smartphone use are limited. In this study, we investigated functional connectivity in problematic smartphone users, focusing on the default mode network (DMN) and attentional networks. We hypothesized that problematic smartphone users would have alterations in functional connectivity between the DMN and attentional networks and that such alterations would correlate with the severity of problematic smartphone use. This study included 30 problematic smartphone users and 35 non-problematic smartphone users. We carried out group independent component analysis (group ICA) to decompose resting-state functional magnetic resonance imaging (fMRI) data into distinct networks. We examined functional connectivity using seed-to-seed analysis and identified the nodes of networks in group ICA, which we used as region of interest. We identified greater functional connectivity of the dorsal anterior cingulate cortex (dACC) with the ventral attention network (VAN) and with the DMN in problematic smartphone users. In seed-to-seed analysis, problematic smartphone users showed atypical dACC-VAN functional connectivity which correlated with the smartphone addiction proneness scale total scores. Our resting-state fMRI study found greater functional connectivity between the dACC and attentional networks in problematic smartphone users. Our findings suggest that increased bottom-up and interoceptive attentional processing might play an important role in problematic smartphone use.

PMID:36262635 | PMC:PMC9573940 | DOI:10.3389/fpsyt.2022.1008557

Intrinsic connectivity within the affective salience network moderates adolescent susceptibility to negative and positive peer norms

Wed, 10/19/2022 - 10:00

Sci Rep. 2022 Oct 19;12(1):17463. doi: 10.1038/s41598-022-17780-1.


Not all adolescents are equally susceptible to peer influence, and for some, peer influence exerts positive rather than negative effects. Using resting-state functional magnetic resonance imaging, the current study examined how intrinsic functional connectivity networks associated with processing social cognitive and affective stimuli predict adolescents' (n = 87, ages 11-14 years) prosocial tendencies and risky behaviors in the context of positive and negative peer norms. We tested the moderating role of four candidate intrinsic brain networks-associated with mentalizing, cognitive control, motivational relevance, and affective salience-in peer influence susceptibility. Only intrinsic connectivity within the affective salience network significantly moderated the association between peer norms and adolescent behavior above and beyond the other networks. Adolescents with high intrinsic connectivity within the affective salience network reported greater prosocial tendencies in contexts with more positive peer norms but greater risk-taking behavior in contexts with more negative peer norms. In contrast, peer norms were not associated with adolescent behavior for individuals with low affective salience within-network intrinsic connectivity. The mentalizing network, cognitive control network, and motivational relevance network were not associated with individual differences in peer influence susceptibility. This study identifies key neural mechanisms underlying differential susceptibility to positive and negative peer influence in early adolescence, with a particular emphasis on the role of affective salience over traditional mentalizing, regulatory, and motivational processes.

PMID:36261429 | DOI:10.1038/s41598-022-17780-1

Functional brain network and trail making test changes following major surgery and postoperative delirium: a prospective, multicentre, observational cohort study

Wed, 10/19/2022 - 10:00

Br J Anaesth. 2022 Oct 4:S0007-0912(22)00464-0. doi: 10.1016/j.bja.2022.07.054. Online ahead of print.


BACKGROUND: Delirium is a frequent complication after surgery in older adults and is associated with an increased risk of long-term cognitive impairment and dementia. Disturbances in functional brain networks were previously reported during delirium. We hypothesised that alterations in functional brain networks persist after remission of postoperative delirium and that functional brain network alterations are associated with long-term cognitive impairment.

METHODS: In this prospective, multicentre, observational cohort study, we included older patients who underwent clinical assessments (including the Trail Making Test B [TMT-B]) and resting-state functional MRI (rs-fMRI) before and 3 months after elective surgery. Delirium was assessed on the first seven postoperative days.

RESULTS: Of the 554 enrolled patients, 246 remained after strict motion correction, of whom 38 (16%) developed postoperative delirium. The rs-fMRI functional connectivity strength increased 3 months after surgery in the total study population (β=0.006; 95% confidence interval [CI]: 0.001-0.011; P=0.013), but it decreased after postoperative delirium (β=-0.015; 95% CI: -0.028 to 0.002; P=0.023). No difference in TMT-B scores was found at follow-up between patients with and without postoperative delirium. Patients with decreased functional connectivity strength declined in TMT-B scores compared with those who did not (β=11.04; 95% CI: 0.85-21.2; P=0.034).

CONCLUSIONS: Postoperative delirium was associated with decreased brain functional connectivity strength after 3 months, suggesting that delirium has a long-lasting impact on brain networks. The decreased connectivity strength was associated with significant cognitive deterioration after major surgery.


PMID:36261307 | DOI:10.1016/j.bja.2022.07.054

Invariant structural and functional brain regions associated with tinnitus: A meta-analysis

Tue, 10/18/2022 - 10:00

PLoS One. 2022 Oct 18;17(10):e0276140. doi: 10.1371/journal.pone.0276140. eCollection 2022.


Tinnitus is a common, functionally disabling condition of often unknown etiology. Neuroimaging research to better understand tinnitus is emerging but remains limited in scope. Voxel-based physiology (VBP) studies detect tinnitus-associated pathophysiology by group-wise contrast (tinnitus vs controls) of resting-state indices of hemodynamics, metabolism, and neurovascular coupling. Voxel-based morphometry (VBM) detects tinnitus-associated neurodegeneration by group-wise contrast of structural MRI. Both VBP and VBM studies routinely report results as atlas-referenced coordinates, suitable for coordinate-based meta-analysis (CBMA). Here, 17 resting-state VBP and 8 VBM reports of tinnitus-associated regional alterations were meta-analyzed using activation likelihood estimation (ALE). Acknowledging the need for data-driven insights, ALEs were performed at two levels of statistical rigor: corrected for multiple comparisons and uncorrected. The corrected ALE applied cluster-level inference thresholding by intensity (z-score > 1.96; p < 0.05) followed by family-wise error correction for multiple comparisons (p < .05, 1000 permutations) and fail-safe correction for missing data. The corrected analysis identified one significant cluster comprising five foci in the posterior cingulate gyrus and precuneus, that is, not within the primary or secondary auditory cortices. The uncorrected ALE identified additional regions within auditory and cognitive processing networks. Taken together, tinnitus is likely a dysfunction of regions spanning multiple canonical networks that may serve to increase individuals' interoceptive awareness of the tinnitus sound, decrease capacity to switch cognitive sets, and prevent behavioral and cognitive attention to other stimuli. It is noteworthy that the most robust tinnitus-related abnormalities are not in the auditory system, contradicting collective findings of task-activation literature in tinnitus.

PMID:36256642 | PMC:PMC9578602 | DOI:10.1371/journal.pone.0276140

Aberrant Topological Properties of Brain Functional Network in Children with Obstructive Sleep Apnea Derived from Resting-State fMRI

Tue, 10/18/2022 - 10:00

Brain Topogr. 2022 Oct 18. doi: 10.1007/s10548-022-00920-1. Online ahead of print.


To examine the difference in the topological properties of brain functional network between the children with obstructive sleep apnea (OSA) and healthy controls, and to explore the relationships between these properties and cognitive scores of OSA children. Twenty-four OSA children (6.5 ± 2.8 years, 15 males) and 26 healthy controls (8.0 ± 2.9 years, 11 males) underwent resting-state fMRI (rs-fMRI), based on which brain functional networks were constructed. We compared the global and regional topological properties of the network between OSA children and healthy controls. Partial correlation analysis was performed between topological properties and cognitive scores across OSA children. When comparing the OSA children with the healthy controls, lower full-scale intelligent quotient (FIQ) and verbal intelligent quotient (VIQ) were observed. Additionally, nodal degree centrality decreased in the bilateral anterior cingulate and paracingulate gyrus, but increased in the right middle frontal gyrus, the left fusiform gyrus, and the left supramarginal gyrus. Nodal efficiency decreased in the right precentral gyrus, and the bilateral anterior cingulate and paracingulate gyrus, but increased in the left fusiform gyrus. Nodal betweenness centrality increased in the dorsolateral part of the right superior frontal gyrus, the left fusiform gyrus, and the left supramarginal gyrus. Further, the nodal degree centrality in the left supramarginal gyrus was positively correlated with FIQ. In contrast, none of global topological properties showed difference between those two groups. The outcomes of OSA may impaired the regional topological properties of the brain functional network of OSA children, which may be potential neural mechanism underlying the cognitive declines of these patients.

PMID:36258117 | DOI:10.1007/s10548-022-00920-1

Functional magnetic resonance imaging, deep learning, and Alzheimer's disease: A systematic review

Tue, 10/18/2022 - 10:00

J Neuroimaging. 2022 Oct 18. doi: 10.1111/jon.13063. Online ahead of print.


Alzheimer's disease (AD) is currently diagnosed using a mixture of psychological tests and clinical observations. However, these diagnoses are not perfect, and additional diagnostic tools (e.g., MRI) can help improve our understanding of AD as well as our ability to detect the disease. Accordingly, a large amount of research has been invested into innovative diagnostic methods for AD. Functional MRI (fMRI) is a form of neuroimaging technology that has been used to diagnose AD; however, fMRI is incredibly noisy, complex, and thus lacks clinical use. Nonetheless, recent innovations in deep learning technology could enable the simplified and streamlined analysis of fMRI. Deep learning is a form of artificial intelligence that uses computer algorithms based on human neural networks to solve complex problems. For example, in fMRI research, deep learning models can automatically denoise images and classify AD by detecting patterns in participants' brain scans. In this systematic review, we investigate how fMRI (specifically resting-state fMRI) and deep learning methods are used to diagnose AD. In turn, we outline the common deep neural network, preprocessing, and classification methods used in the literature. We also discuss the accuracy, strengths, limitations, and future direction of fMRI deep learning methods. In turn, we aim to summarize the current field for new researchers, suggest specific areas for future research, and highlight the potential of fMRI to aid AD diagnoses.

PMID:36257926 | DOI:10.1111/jon.13063

Maladaptive laterality in cortical networks related to social communication in autism spectrum disorder

Tue, 10/18/2022 - 10:00

J Neurosci. 2022 Oct 17:JN-RM-1229-22. doi: 10.1523/JNEUROSCI.1229-22.2022. Online ahead of print.


Neuroimaging studies of individuals with autism spectrum disorders (ASD) consistently find an aberrant pattern of "reduced" laterality in brain networks that support functions related to social communication and language. However, it is unclear how the underlying functional organization of these brain networks is altered in ASD individuals. We tested four models of "reduced" laterality in a social-communication network in seventy ASD individuals (14 females) and a control group of the same number of tightly matched typically developing (TD) individuals (19 females) using high quality resting-state fMRI data and a method of measuring patterns of functional laterality across the brain. We found that a functionally defined social-communication network exhibited the typical pattern of left laterality in both groups, while there was a significant increase in within- relative to across-hemisphere connectivity of homotopic regions in the right hemisphere in ASD individuals. Furthermore, greater within- relative to across-hemisphere connectivity in the left hemisphere was positively correlated with a measure of verbal ability in both groups, while greater within- relative to across-hemisphere connectivity in the right hemisphere in ASD, but not TD, individuals was negatively correlated with the same verbal measure. Crucially, these differences in patterns of laterality were not found in two other functional networks and were specifically correlated to a measure of verbal ability, but not metrics of other core components of the ASD phenotype. These results suggest that previous reports of "reduced" laterality in social-communication regions in ASD is due to the two hemispheres functioning more independently than seen in TD individuals, with the atypical right-hemisphere network component being maladaptive.SIGNIFICANCE STATEMENT:A consistent neuroimaging finding in individuals with autism spectrum disorders (ASD) is an aberrant pattern of "reduced" laterality of the brain networks that support functions related to social communication and language. We tested four models of "reduced" laterality in a social-communication network in ASD individuals and a typically developing (TD) control group using high quality resting-state fMRI data. Our results suggest that "reduced" laterality of social-communication regions in ASD may be due to the two hemispheres functioning more independently than seen in TD individuals, with atypically greater within- than across-hemisphere connectivity in the right hemisphere being maladaptive.

PMID:36257690 | DOI:10.1523/JNEUROSCI.1229-22.2022

Venglustat combined with imiglucerase for neurological disease in adults with Gaucher disease type 3: the LEAP trial

Tue, 10/18/2022 - 10:00

Brain. 2022 Oct 18:awac379. doi: 10.1093/brain/awac379. Online ahead of print.


Gaucher disease type 3 (GD3) is a chronic neuronopathic disorder with wide-ranging effects, including hepatosplenomegaly, anaemia, thrombocytopenia, skeletal disease, and diverse neurological manifestations. Biallelic mutations in GBA1 reduce lysosomal acid β-glucosidase activity, and its substrates, glucosylceramide and glucosylsphingosine, accumulate. Enzyme replacement therapy (ERT) and substrate reduction therapy (SRT) ameliorate systemic features of Gaucher disease, but no therapies are approved for neurological manifestations. Venglustat is an investigational, brain-penetrant, glucosylceramide synthase inhibitor with potential to improve the disease by rebalancing influx of glucosylceramide with impaired lysosomal recycling. The Phase 2, open-label LEAP trial (NCT02843035) evaluated orally administered venglustat 15 mg once daily in combination with maintenance dose of imiglucerase ERT during one year of treatment in eleven adults with GD3. Primary endpoints were venglustat safety and tolerability and change in concentration of glucosylceramide and glucosylsphingosine in CSF from baseline to Week 26 and Week 52. Secondary endpoints included change in plasma concentrations of glucosylceramide and glucosylsphingosine, venglustat pharmacokinetics in plasma and CSF, neurologic function, infiltrative lung disease and systemic disease parameters. Exploratory endpoints included changes in brain volume assessed with volumetric MRI (vMRI) using tensor-based morphometry, and resting functional MRI (fMRI) analysis of regional brain activity and connectivity between resting state networks. Mean (SD) plasma venglustat AUC0-24 on Day 1 was 851 (282) ng•hr/mL; Cmax of 58.1 (26.4) ng/mL was achieved at a median tmax 2.00 hours. After once-daily venglustat, plasma concentrations (4 hours post dose) were higher compared with Day 1, indicating approximately 2-fold accumulation. One participant (Patient 9) had low-to-undetectable venglustat exposure at Weeks 26 and 52. Based on mean plasma and CSF venglustat concentrations (excluding Patient 9), steady state appeared to be reached on or before Week 4. Mean (SD) venglustat concentration at Week 52 was 114 (65.8) ng/mL in plasma and 6.14 (3.44) ng/mL in CSF. After one year of treatment, median (IQR) glucosylceramide decreased 78% (72, 84) in plasma and 81% (77, 83) in CSF; median (IQR) glucosylsphingosine decreased 56% (41, 60) in plasma and 70% (46, 76) in CSF. Ataxia improved slightly in nine patients: mean (SD, range) total modified SARA score decreased from 2.68 (1.54 [0.0 to 5.5]) at baseline to 1.55 (1.88 [0.0 to 5.0]) at Week 52 (mean change: -1.14 [95% CI: -2.06 to -0.21]). Whole brain volume increased slightly in patients with venglustat exposure and biomarker reduction in CSF (306.7 ± 4253.3 mm3) and declined markedly in Patient 9 (-13894.8 mm3). fMRI indicated stronger connectivity at Weeks 26 and 52 relative to baseline between a broadly distributed set of brain regions in patients with venglustat exposure and biomarker reduction but not Patient 9, although neurocognition, assessed by Vineland II, deteriorated in all domains over time, which illustrates disease progression despite the intervention. There were no deaths, serious adverse events or discontinuations. In adults with GD3 receiving imiglucerase, addition of once-daily venglustat showed acceptable safety and tolerability and preliminary evidence of clinical stability with intriguing but intrinsically inconsistent signals in selected biomarkers, which need to be validated and confirmed in future research.

PMID:36256599 | DOI:10.1093/brain/awac379

Classification of primary dysmenorrhea by brain effective connectivity of the amygdala: a machine learning study

Tue, 10/18/2022 - 10:00

Brain Imaging Behav. 2022 Oct 18. doi: 10.1007/s11682-022-00707-9. Online ahead of print.


BACKGROUND: The amygdala plays a crucial role in the central pathogenesis mechanism of primary dysmenorrhea (PDM). However, the detailed pain modulation principles of the amygdala in PDM remain unclear. Here, we applied the Granger causality analysis (GCA) to investigate the directional effective connectivity (EC) alterations in the amygdala network of PDM patients.

METHODS: Thirty-seven patients with PDM and 38 healthy controls were enrolled in this study and underwent resting-state functional magnetic resonance imaging scans during the pain-free stage. GCA was employed to explore the amygdala-based EC network alteration in PDM. A multivariate pattern analysis (MVPA)-based machine learning approach was used to explore whether the altered amygdala EC could serve as an fMRI-based marker for classifying PDM and HC participants.

RESULTS: Compared to the healthy control group, patients with PDM showed significantly decreased EC from the amygdala to the right superior frontal gyrus (SFG), right superior parietal lobe/middle occipital gyrus, and left middle cingulate cortex, whereas increased EC was found from the amygdala to the bilateral medial orbitofrontal cortex. In addition, increased EC was found from the bilateral SFG to the amygdala, and decreased EC was found from the medial orbitofrontal cortex, caudate nucleus to the amygdala. The increased EC from the right SFG to the amygdala was associated with a plasma prostaglandin E2 level in PDM. The MVPA based on an altered amygdala EC pattern yielded a total accuracy of 86.84% for classifying the patients with PDM and HC.

CONCLUSION: Our study is the first to combine MVPA and EC to explore brain function alteration in PDM. The results could advance understanding of the neural theory of PDM in specifying the pain-free period.

PMID:36255666 | DOI:10.1007/s11682-022-00707-9

Resting-state functional connectivity in adults with 47,XXX: a 7 Tesla MRI study

Tue, 10/18/2022 - 10:00

Cereb Cortex. 2022 Oct 18:bhac410. doi: 10.1093/cercor/bhac410. Online ahead of print.


Triple X syndrome is a sex chromosomal aneuploidy characterized by the presence of a supernumerary X chromosome, resulting in a karyotype of 47,XXX in affected females. It has been associated with a variable cognitive, behavioral, and psychiatric phenotype, but little is known about its effects on brain function. We therefore conducted 7 T resting-state functional magnetic resonance imaging and compared data of 19 adult individuals with 47,XXX and 21 age-matched healthy control women using independent component analysis and dual regression. Additionally, we examined potential relationships between social cognition and social functioning scores, and IQ, and mean functional connectivity values. The 47,XXX group showed significantly increased functional connectivity of the fronto-parietal resting-state network with the right postcentral gyrus. Resting-state functional connectivity (rsFC) variability was not associated with IQ and social cognition and social functioning deficits in the participants with 47,XXX. We thus observed an effect of a supernumerary X chromosome in adult women on fronto-parietal rsFC. These findings provide additional insight into the role of the X chromosome on functional connectivity of the brain. Further research is needed to understand the clinical implications of altered rsFC in 47,XXX.

PMID:36255323 | DOI:10.1093/cercor/bhac410