From anatomy to function: the role of the somatosensory cortex in emotional regulation

Sensory and motor cortices parcellations estimated via distance-weighted sparse representation with application to autism spectrum disorder

BACKGROUND

Motor impairments and sensory processing abnormalities are prevalent in autism spectrum disorder (ASD), closely related to the core functions of the primary motor cortex (M1) and the primary somatosensory cortex (S1). Currently, there is limited knowledge about potential therapeutic targets in the subregions of M1 and S1 in ASD patients. This study aims to map clinically significant functional subregions of M1 and S1.

METHODS

Resting-state functional magnetic resonance imaging data (NTD = 266) from Autism Brain Imaging Data Exchange (ABIDE) were used for subregion modeling. We proposed a distance-weighted sparse representation algorithm to construct brain functional networks. Functional subregions of M1 and S1 were identified through consensus clustering at the group level. Differences in the characteristics of functional subregions were analyzed, along with their correlation with clinical scores.

RESULTS

We observed symmetrical and continuous subregion organization from dorsal to ventral aspects in M1 and S1, with M1 subregions conforming to the functional pattern of the motor homunculus. Significant intergroup differences and clinical correlations were found in the dorsal and ventral aspects of M1 (p < 0.05/3, Bonferroni correction) and the ventromedial BA3 of S1 (p < 0.05/5). These functional characteristics were positively correlated with autism severity. All subregions showed significant results in the ROI-to-ROI intergroup differential analysis (p < 0.05/80).

LIMITATIONS

The generalizability of the segmentation model requires further evaluation.

CONCLUSIONS

This study highlights the significance of M1 and S1 in ASD treatment and may provide new insights into brain parcellation and the identification of therapeutic targets for ASD.

The different impacts of pain-related negative emotion and trait negative emotion on brain function in patients with inflammatory bowel disease

Inflammatory bowel diseases (IBD) are a group of chronic, non-specific intestinal diseases that could comorbid with varieties of negative emotional constructs, including pain-related negative emotions and trait negative emotions; however, the link between brain functions and different dimensions of negative emotions remains largely unknown. Ninety-eight patients with IBD and forty-six healthy subjects were scanned using a 3.0-T functional magnetic resonance imaging scanner. The amplitudes of low-frequency fluctuation (ALFF), regional homogeneity (ReHo), and degree centrality (DC) were used to assess resting-state brain activity. Partial least squares (PLS) correlation was employed to assess the relationship among abnormal brain activities, pain-related and trait negative emotions. Compared to controls, patients with IBD exhibited higher values of ALFF in the right anterior cingulate cortex (ACC), lower values of ALFF in the left postcentral gyrus, and higher values of DC in the bilateral ACC. Multivariate PLS correlation analysis revealed the brain scores of the ACC were correlated with pain-related negative emotions, the brain salience in the left postcentral gyrus was associated with the higher-order trait depression. These findings can enhance our comprehension of how pain-related negative emotion and trait negative emotion affect the brains of patients with IBD in distinct ways.

Exploring spontaneous brain activity changes in high-altitude smokers: Insights from ALFF/fALFF analysis

INTRODUCTION

This study aims to explore the impact of smoking on intrinsic brain activity among high-altitude (HA) populations. Smoking is associated with various neural alterations, but it remains unclear whether smokers in HA environments exhibit specific neural characteristics.

METHODS

We employed ALFF and fALFF methods across different frequency bands to investigate differences in brain functional activity between high-altitude smokers and non-smokers. 31 smokers and 31 non-smokers from HA regions participated, undergoing resting-state functional magnetic resonance imaging (rs-fMRI) scans. ALFF/fALFF values were compared between the two groups. Correlation analyses explored relationships between brain activity and clinical data.

RESULTS

Smokers showed increased ALFF values in the right superior frontal gyrus (R-SFG), right middle frontal gyrus (R-MFG), right anterior cingulate cortex (R-ACC), right inferior frontal gyrus (R-IFG), right superior/medial frontal gyrus (R-MSFG), and left SFG compared to non-smokers in HA. In sub-frequency bands (0.01-0.027 Hz and 0.027-0.073 Hz), smokers showed increased ALFF values in R-SFG, R-MFG, right middle cingulate cortex (R-MCC), R-MSFG, Right precentral gyrus and L-SFG while decreased fALFF values were noted in the right postcentral and precentral gyrus in the 0.01-0.027 Hz band. Negative correlations were found between ALFF values in the R-SFG and smoking years.

CONCLUSION

Our study reveals the neural characteristics of smokers in high-altitude environments, highlighting the potential impact of smoking on brain function. These results provide new insights into the neural mechanisms of high-altitude smoking addiction and may inform the development of relevant intervention measures.

Altered brain function in treatment-resistant depression patients: A resting-state functional magnetic resonance imaging study

BACKGROUND

It has been established that there are functional changes in the brain of treatment-resistant depression (TRD) patients, but previous studies of functional connectivity (FC) usually involved selection of regions of interest based on accumulated a priori knowledge of the disorder. In this study, we combine amplitude of low-frequency fluctuation (ALFF) and FC; this approach, based on the abnormal ALFF, may provide some insights into the neural basis of the disease in terms of fMRI signals of low-frequency fluctuations.

METHODS

A total of 16 TRD patients, who visited the Qingdao Mental Health Center, Shandong Province, China between March 2023 and January 2024, along with 16 normal subjects, were enrolled into this study for functional imaging. In this study, we first explored the ALFF changes of TRD patients at a baseline resting state. Second, we selected the regions that were significantly changed in the ALFF as seeds and calculated the regional activity and functional connectivity (FC) of these regions using a seed-based approach. We also calculated correlations between the percent change in the PDQ-5D scores and ALFF values in brain regions with differing activity for TRD patients.

RESULTS

During the baseline resting state, by using the ALFF, we found a significantly decreased or increased ALFF in the TRD patients relative to the controls. These regions were located in the left/right postcentral gyrus (PoCG.L/PoCG.R), right cuneus(CUN.R). We found that the ALFF values of the right hippocampus (HIP.R) in the TRD group were negatively correlated with the PDQ-5D score. Then, we selected these brain regions as seeds to investigate the FC changes in brains of TRD patients. We found abnormal functional connectivity in left/right middle frontal gyrus(MFG.L/MFG.R), the right Inferior frontal gyrus, opercular part (IFGoperc.R), the left/right Anterior cingulate and paracingulate gyri (ACC.L/ACC.R), the right supramarginal gyrus (SMG.R), and the right Calcarine fissure and surrounding cortex (CAL.R).

CONCLUSION

We found a larger range of altered brain regions in TRD patients compared to healthy controls, especially in the central executive network (CEN), salience network (SN) and default mode network (DMN).

Deficits in prefrontal metabotropic glutamate receptor 5 are associated with functional alterations during emotional processing in bipolar disorder

BACKGROUND

Elucidating biological mechanisms contributing to bipolar disorder (BD) is key to improved diagnosis and treatment development. With converging evidence implicating the metabotropic glutamate receptor 5 (mGlu5) in the pathology of BD, here, we therefore test the hypothesis that recently identified deficits in mGlu5 are associated with functional brain differences during emotion processing in BD.

METHODS

Positron emission tomography (PET) with [18F]FPEB was used to measure mGlu5 receptor availability and functional imaging (fMRI) was performed while participants completed an emotion processing task. Data were analyzed from 62 individuals (33 ± 12 years, 45 % female) who completed both PET and fMRI, including individuals with BD (n = 18), major depressive disorder (MDD: n = 20), and psychiatrically healthy comparisons (HC: n = 25).

RESULTS

Consistent with some prior reports, the BD group displayed greater activation during fear processing relative to MDD and HC, notably in right lateralized frontal and parietal brain regions. In BD, (but not MDD or HC) lower prefrontal mGlu5 availability was associated with greater activation in bilateral pre/postcentral gyri and cuneus during fear processing. Furthermore, greater prefrontal mGlu5-related brain activity in BD was associated with difficulties in psychomotor function (r≥0.904, p≤0.005) and attention (r≥0.809, p≤0.028).

LIMITATIONS

The modest sample size is the primary limitation.

CONCLUSIONS

Deficits in prefrontal mGlu5 in BD were linked to increased cortical activation during fear processing, which in turn was associated with impulsivity and attentional difficulties. These data further implicate an mGlu5-related mechanism unique to BD. More generally these data suggest integrating PET and fMRI can provide novel mechanistic insights.

Cell-Type-Specific Expression of Leptin Receptors in the Mouse Forebrain

Leptin is a hormone produced by the small intestines and adipose tissue that promotes feelings of satiety. Leptin receptors (LepRs) are highly expressed in the hypothalamus, enabling central neural control of hunger. Interestingly, LepRs are also expressed in several other regions of the body and brain, notably in the cerebral cortex and hippocampus. These brain regions mediate higher-order sensory, motor, cognitive, and memory functions, which can be profoundly altered during periods of hunger and satiety. However, LepR expression in these regions has not been fully characterized on a cell-type-specific basis, which is necessary to begin assessing their potential functional impact. Consequently, we examined LepR expression on neurons and glia in the forebrain using a LepR-Cre transgenic mouse model. LepR-positive cells were identified using a 'floxed' viral cell-filling approach and co-labeling immunohistochemically for cell-type-specific markers, i.e., NeuN, VGlut2, GAD67, parvalbumin, somatostatin, 5-HT3R, WFA, S100β, and GFAP. In the cortex, LepR-positive cells were localized to lower layers (primarily layer 6) and exhibited non-pyramidal cellular morphologies. The majority of cortical LepR-positive cells were neurons, while the remainder were identified primarily as astrocytes or other glial cells. The majority of cortical LepR-positive neurons co-expressed parvalbumin, while none expressed somatostatin or 5-HT3R. In contrast, all hippocampal LepR-positive cells were neuronal, with none co-expressing GFAP. These data suggest that leptin can potentially influence neural processing in forebrain regions associated with sensation and limbic-related functions.

Enhanced generalization and specialization of brain representations of semantic knowledge in healthy aging

Aging is often associated with a decrease in cognitive capacities. However, semantic memory appears relatively well preserved in healthy aging. Both behavioral and neuroimaging studies support the view that changes in brain networks contribute to this preservation of semantic cognition. However, little is known about the role of healthy aging in the brain representation of semantic categories. Here we used pattern classification analyses and computational models to examine the neural representations of living and non-living word concepts. The results demonstrate that brain representations of animacy in healthy aging exhibit increased similarity across categories, even across different task contexts. This pattern of results aligns with the neural dedifferentiation hypothesis that proposes that aging is associated with decreased specificity in brain activity patterns and less efficient neural resource allocation. However, the loss in neural specificity for different categories was accompanied by increased dissimilarity of item-based conceptual representations within each category. Taken together, the age-related patterns of increased generalization and specialization in the brain representations of semantic knowledge may reflect a compensatory mechanism that enables a more efficient coding scheme characterized by both compression and sparsity, thereby helping to optimize the limited neural resources and maintain semantic processing in the healthy aging brain.

Association between clinical features and decreased degree centrality and variability in dynamic functional connectivity in the obsessive-compulsive disorder

Neuroimaging studies have indicated widespread brain structural and functional disruptions in patients with obsessive-compulsive disorder (OCD). However, the underlying mechanism of these changes remains unclear. A total of 45 patients with OCD and 42 healthy controls (HC) were enrolled. The study investigated local degree centrality (DC) abnormalities and employed abnormal regions of DC as seeds to investigate variability in dynamic functional connectivity (dFC) in the whole brain using a sliding window approach to analyze resting-state functional magnetic resonance imaging. The relationship between abnormal DC and dFC as well as the clinical features of OCD were examined using correlation analysis. Our findings suggested decreased DC in the bilateral thalamus, bilateral precuneus, and bilateral cuneus in OCD patients and a nominally negative correlation between the DC value in the thalamus and illness severity measured using the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). In addition, seed-based dFC analysis showed that compared to measurements in the HC, the patients had decreased dFC variability between the left thalamus and the left cuneus and right lingual gyrus, and between the bilateral cuneus and bilateral postcentral gyrus, and a nominally positive correlation between the duration of illness and dFC variability between the left cuneus and left postcentral gyrus. These results indicated that OCD patients had decreased hub importance in the bilateral thalamus and cuneus throughout the entire brain. This reduction was associated with impaired coupling with dynamic function in the visual cortex and sensorimotor network and provided novel insights into the neurophysiological mechanisms underlying OCD.

Accurate identification of individuals with subjective cognitive decline using 3D regional fractal dimensions on structural magnetic resonance imaging

BACKGROUND AND OBJECTIVE

Accurate identification of individuals with subjective cognitive decline (SCD) is crucial for early intervention and prevention of neurodegenerative diseases. Fractal dimensionality (FD) has emerged as a robust and replicable measure, surpassing traditional geometric metrics, in characterizing the intricate fractal geometrical properties of brain structure. Nevertheless, the effectiveness of FD in identifying individuals with SCD remains largely unclear. A 3D regional FD method can be suggested to characterize and quantify the spatial complexity of the precise gray matter, providing insights into cognitive aging and aiding in the automated identification of individuals with SCD.

METHODS

This study introduces a novel integer ratio based 3D box-counting fractal analysis (IRBCFA) to quantify regional fractal dimensions (FDs) in structural magnetic resonance imaging (MRI) data. The innovative method overcomes limitations of conventional box-counting techniques by accommodating arbitrary box sizes, thereby enhancing the precision of FD estimation in small, yet neurologically significant, brain regions.

RESULTS

The application of IRBCFA to two publicly available datasets, OASIS-3 and ADNI, consisting of 520 and 180 subjects, respectively. The method identified discriminative regions of interest (ROIs) predominantly within the limbic system, fronto-parietal region, occipito-temporal region, and basal ganglia-thalamus region. These ROIs exhibited significant correlations with cognitive functions, including executive functioning, memory, social cognition, and sensory perception, suggesting their potential as neuroimaging markers for SCD. The identification model trained on these ROIs demonstrated exceptional performance achieving over 93 % accuracy on the discovery dataset and exceeding 87 % on the independent testing dataset. Furthermore, an exchange experiment between datasets revealed a substantial overlap in discriminative ROIs, highlighting the robustness of our method across diverse populations.

CONCLUSION

Our findings indicate that IRBCFA can serve as a valuable tool for quantifying the spatial complexity of gray matter, providing insights into cognitive aging and aiding in the automated identification of individuals with SCD. The demonstrated generalizability and robustness of this method position it as a promising tool for neurodegenerative disease research and offer potential for clinical applications.

Neural foundation of the diathesis-stress model: longitudinal gray matter volume changes in response to stressful life events in major depressive disorder and healthy controls

Recurrences of depressive episodes in major depressive disorder (MDD) can be explained by the diathesis-stress model, suggesting that stressful life events (SLEs) can trigger MDD episodes in individuals with pre-existing vulnerabilities. However, the longitudinal neurobiological impact of SLEs on gray matter volume (GMV) in MDD and its interaction with early-life adversity remains unresolved. In 754 participants aged 18-65 years (362 MDD patients; 392 healthy controls; HCs), we assessed longitudinal associations between SLEs (Life Events Questionnaire) and whole-brain GMV changes (3 Tesla MRI) during a 2-year interval, using voxel-based morphometry in SPM12/CAT12. We also explored the potential moderating role of childhood maltreatment (Childhood Trauma Questionnaire) on these associations. Over the 2-year interval, HCs demonstrated significant GMV reductions in the middle frontal, precentral, and postcentral gyri in response to higher levels of SLEs, while MDD patients showed no such GMV changes. Childhood maltreatment did not moderate these associations in either group. However, MDD patients who had at least one depressive episode during the 2-year interval, compared to those who did not, or HCs, showed GMV increases in the middle frontal, precentral, and postcentral gyri associated with an increase in SLEs and childhood maltreatment. Our findings indicate distinct GMV changes in response to SLEs between MDD patients and HCs. GMV decreases in HCs may represent adaptive responses to stress, whereas GMV increases in MDD patients with both childhood maltreatment and a depressive episode during the 2-year interval may indicate maladaptive changes, suggesting a neural foundation for the diathesis-stress model in MDD recurrences.

Effects of computerized working memory training on neuroplasticity in healthy individuals: A combined neuroimaging and neurotransmitter study

Working memory (WM) is an essential cognitive function that underpins various higher-order cognitive processes. Improving WM capacity through targeted training interventions has emergered as a potential approach for enhancing cognitive abilities. The present study employed an 8-week regimen of computerized WM training (WMT) to investigate its effect on neuroplasticity in healthy individuals, utilizing neuroimaging data gathered both before and after the training. The key metrics assessed included the amplitude of low-frequency fluctuations (ALFF), voxel-based morphometry (VBM), and the spatial distribution correlations of neurotransmitter. The results indicated that post-training, compared to baseline, there was a reduction in ALFF in the medial superior frontal gyrus and an elevation in ALFF in the left middle occipital gyrus within the training group. In comparison to the control group, the training group also exhibited decreased ALFF in the anterior cingulate cortex, angular gyrus, and superior parietal lobule, along with increased ALFF in the postcentral gyrus post-training. VBM analysis revealed a significant increase in gray matter volume (GMV) in the right dorsal superior frontal gyrus after the training period, compared to the initial baseline measurement. Furthermore, the training group showed GMV increases in the dorsal superior frontal gyrus, Rolandic operculum, precentral gyrus, and postcentral gyrus when compared to the control group. In addition, significant associations were identifed between neuroimaging measurements (AFLL and VBM) and the spatial patterns of neurotransmitters such as serotonin (5-HT), dopamine (DA), and N-methyl-D-aspartate (NMDA), providing insights into the underlying neurochemical processes. These findings clarify the neuroplastic changes caused by WMT, offering a deeper understanding of brain plasticity and highlighting the potential advantages of cognitive training interventions.

Comparison of Resting-State Functional Connectivity Between Generalized Anxiety Disorder and Social Anxiety Disorder: Differences in the Nucleus Accumbens and Thalamus Network

Background: Generalized anxiety disorder (GAD) and social anxiety disorder (SAD) are distinguished by whether anxiety is limited to social situations. However, reports on the differences in brain functional networks between GAD and SAD are few. Our objective is to understand the pathogenesis of GAD and SAD by examining the differences in resting brain function between patients with GAD and SAD and healthy controls (HCs). Methods: This study included 21 patients with SAD, 17 patients with GAD, and 30 HCs. Participants underwent psychological assessments and resting-state functional magnetic resonance imaging. Whole-brain analyses were performed to compare resting-state functional connectivity (rsFC) among the groups. In addition, logistic regression analysis was conducted on the rsFC to identify significant differences between GAD and SAD. Results: Patients with SAD and GAD had significantly higher rsFC between the bilateral postcentral gyri and bilateral amygdalae/thalami than HCs. Compared with patients with SAD, those with GAD had significantly higher rsFC between the right nucleus accumbens and bilateral thalami and between the left nucleus accumbens and right thalamus. rsFC between the left nucleus accumbens and right thalamus positively correlated with state anxiety in patients with SAD and GAD, respectively. In addition, logistic regression analysis revealed that the right nucleus accumbens and the right thalamus connectivity could distinguish SAD from GAD. Conclusions: GAD and SAD were distinguished by the right nucleus accumbens and the right thalamus connectivity. Our findings offer insights into the disease-specific neural basis of SAD and GAD. Clinical Trial Registration Number: M10545. Impact Statement This study is the first to identify a resting state functional connectivity that distinguishes social anxiety disorder (SAD) from generalized anxiety disorder (GAD) and to clarify a common connectivity in both disorders. We found that the connectivity between the right nucleus accumbens and the right thalamus differentiated SAD from GAD. Furthermore, these rsFC differences suggest an underlying basis for fear overgeneralization. Our findings shed light on the pathophysiology of these conditions and could be used as a basis for further studies to improve outcomes for such patients.

Decoding acceptance and reappraisal strategies from resting state macro networks

Acceptance and reappraisal are considered adaptive emotion regulation strategies. While previous studies have explored the neural underpinnings of these strategies using task-based fMRI and sMRI, a gap exists in the literature concerning resting-state functional brain networks' contributions to these abilities, especially regarding acceptance. Another intriguing question is whether these strategies rely on similar or different neural mechanisms. Building on the well-known improved emotion regulation and increased cognitive flexibility of individuals who rely on acceptance, we expected to find decreased activity inside the affective network and increased activity inside the executive and sensorimotor networks to be predictive of acceptance. We also expect that these networks may be associated at least in part with reappraisal, indicating a common mechanism behind different strategies. To test these hypotheses, we conducted a functional connectivity analysis of resting-state data from 134 individuals (95 females; mean age: 30.09 ± 12.87 years, mean education: 12.62 ± 1.41 years). To assess acceptance and reappraisal abilities, we used the Cognitive Emotion Regulation Questionnaire (CERQ) and a group-ICA unsupervised machine learning approach to identify resting-state networks. Subsequently, we conducted backward regression to predict acceptance and reappraisal abilities. As expected, results indicated that acceptance was predicted by decreased affective, and executive, and increased sensorimotor networks, while reappraisal was predicted by an increase in the sensorimotor network only. Notably, these findings suggest both distinct and overlapping brain contributions to acceptance and reappraisal strategies, with the sensorimotor network potentially serving as a core common mechanism. These results not only align with previous findings but also expand upon them, illustrating the complex interplay of cognitive, affective, and sensory abilities in emotion regulation.

Decreased inter-hemispheric cooperation in major depressive disorder and its association with neurotransmitter profiles

BACKGROUND

Inter-hemispheric cooperation is a prominent feature of the human brain, and previous neuroimaging studies have revealed aberrant inter-hemispheric cooperation patterns in patients with major depressive disorder (MDD). Typically, inter-hemispheric cooperation is examined by calculating the functional connectivity (FC) between each voxel in one hemisphere and its anatomical (structurally homotopic) counterpart in the opposite hemisphere. However, bilateral hemispheres are actually asymmetric in anatomy.

METHODS

In the present study, we utilized connectivity between functionally homotopic voxels (CFH) to investigate abnormal inter-hemispheric cooperation in 96 MDD patients compared to 173 age- and sex-matched healthy controls (HCs). In addition, we analyzed the spatial correlations between abnormal CFH and the density maps of 13 neurotransmitter receptors and transporters.

RESULTS

The CFH values in bilateral orbital frontal gyri and bilateral postcentral gyri were abnormally decreased in patients with MDD. Furthermore, these CFH abnormalities were correlated with clinical symptoms. In addition, the abnormal CFH pattern in MDD patients was spatially correlated with the distribution pattern of 5-HT1AR.

LIMITATIONS

drug effect; the cross-sectional research design precludes causal inferences; the neurotransmitter atlases selected were constructed from healthy individuals rather than MDD patients.

CONCLUSION

These findings characterized the abnormal inter-hemispheric cooperation in MDD using a novel method and the underlying neurotransmitter mechanism, which promotes our understanding of the pathophysiology of depression.

Early life psychosocial stress increases binge-like ethanol consumption and CSF1R inhibition prevents stress-induced alterations in microglia and brain macrophage population density

Early life stress (ELS) has lasting consequences on microglia and brain macrophage function. During ELS, microglia and brain macrophages alter their engagement with synapses leading to changes in neuronal excitability. Further, ELS can induce innate immune memory formation in microglia and brain macrophages resulting in altered responsivity to future environmental stimuli. These alterations can result in lasting adaptations in circuit function and may mediate the relationship between ELS and the risk to develop alcohol use disorder (AUD). Whether microglia and brain macrophages truly mediate this relationship remains elusive. Here, we report: 1) an ELS model, psychosocial stress (PSS), increases binge-like ethanol consumption in early adulthood. 2) Repeated binge-like ethanol consumption increases microglia and brain macrophage population densities across the brain. 3) PSS may elicit innate immune memory formation in microglia and brain macrophages leading to altered population densities following repeated binge-like ethanol consumption. 4) Microglia and brain macrophage inhibition trended towards preventing PSS-evoked changes in binge-like ethanol consumption and normalized microglia and brain macrophage population densities. Therefore, our study suggests that acutely inhibiting microglia and brain macrophage function during periods of early life PSS may prevent innate immune memory formation and assist in reducing the risk to develop AUD.

Highlights

An early life psychosocial stress (PSS) exposure increases ethanol consumptionMicroglial inhibition during PSS trends towards reducing ethanol consumptionBinge ethanol consumption increases microglial count and alters cell proximityEarly life PSS alters microglial responsivity to binge ethanol consumptionMicroglial inhibition may prevent microglial innate immune memory formation.

Abnormal large-scale brain functional network dynamics in social anxiety disorder

AIMS

Although static abnormalities of functional brain networks have been observed in patients with social anxiety disorder (SAD), the brain connectome dynamics at the macroscale network level remain obscure. We therefore used a multivariate data-driven method to search for dynamic functional network connectivity (dFNC) alterations in SAD.

METHODS

We conducted spatial independent component analysis, and used a sliding-window approach with a k-means clustering algorithm, to characterize the recurring states of brain resting-state networks; then state transition metrics and FNC strength in the different states were compared between SAD patients and healthy controls (HC), and the relationship to SAD clinical characteristics was explored.

RESULTS

Four distinct recurring states were identified. Compared with HC, SAD patients demonstrated higher fractional windows and mean dwelling time in the highest-frequency State 3, representing "widely weaker" FNC, but lower in States 2 and 4, representing "locally stronger" and "widely stronger" FNC, respectively. In State 1, representing "widely moderate" FNC, SAD patients showed decreased FNC mainly between the default mode network and the attention and perceptual networks. Some aberrant dFNC signatures correlated with illness duration.

CONCLUSION

These aberrant patterns of brain functional synchronization dynamics among large-scale resting-state networks may provide new insights into the neuro-functional underpinnings of SAD.

Spatiotemporal responses to emotional conflict and its psychiatric correlates in adolescents with epilepsy using magnetoencephalography

People with epilepsy often suffer from comorbid psychiatric disorders, which negatively affects their quality of life. Emotion regulation is an important cognitive process that is impaired in individuals with psychiatric disorders, such as depression. Adults with epilepsy also show difficulties in emotion regulation, particularly during later-stage, higher-order cognitive processing. Yet, the spatiotemporal and frequency correlates of these functional brain deficits in epilepsy remain unknown, as do the nature of these deficits in adolescent epilepsy. Here, we aim to elucidate the spatiotemporal profile of emotional conflict processing in adolescents with epilepsy, relative to controls, using magnetoencephalography (MEG) and relate these findings to anxiety and depression symptom severity assessed with self-report scales. We hypothesized to see blunted brain activity during emotional conflict in adolescents with epilepsy, relative to controls, in the posterior parietal, prefrontal and cingulate cortices due to their role in explicit and implicit regulation around participant response (500-1000 ms). We analyzed MEG recordings from 53 adolescents (28 epilepsy [14focal,14generalized], 25 controls) during an emotional conflict task. We showed that while controls exhibited behavioral interference to emotional conflict, adolescents with epilepsy failed to exhibit this normative response time pattern. Adolescents with epilepsy showed blunted brain responses to emotional conflict in brain regions related to error evaluation and learning around the average response time (500-700 ms), and in regions involved in decision making during post-response monitoring (800-1000 ms). Interestingly, behavioral patterns and psychiatric symptom severity varied between epilepsy subgroups, wherein those with focal epilepsy showed preserved response time interference. Thus, brain responses were regressed with depression and anxiety levels for each epilepsy subgroup separately. Analyses revealed that under activation in error evaluation regions (500-600 ms) predicted anxiety and depression in focal epilepsy, while regions related to learning (600-700 ms) predicted anxiety in generalized epilepsy, suggesting differential mechanisms of dysfunction in these subgroups. Despite similar rates of anxiety and depression across the groups, adolescents with epilepsy still exhibited deficits in emotional conflict processing in brain and behavioral responses. This suggests that these deficits may exist independently from psychopathology and may stem from underlying dysfunctions that predispose these individuals to develop both disorders. Findings such as these may provide potential targets for future research and therapies.

The abnormalities of brain function in females with primary insomnia: a resting-state functional magnetic resonance imaging study

Background

The neuropathologic mechanism of primary insomnia (PI) of females remains unclear. This study aims to investigate the features of amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo) in females with PI using functional magnetic resonance imaging (fMRI), and then explore the abnormalities of functional connectivity (FC).

Materials and methods

A total of 39 female PI patients and 31 female healthy controls (HC) were enrolled in the study. The sleep condition was assessed using the Pittsburgh Sleep Quality Index (PSQI), and Insomnia Severity Index (ISI), and their depressive symptom was evaluated using the Hamilton Depression Scale (HAMD-24). The rs-fMRI was once conducted for every subject. ReHo, ALFF, and ROI-based FC were used to analyze the changes of brain function.

Results

ALFF values were increased in the Cerebelum_4_5_L, as well as decreased ALFF in the bilateral Frontal_Sup_Medial (SFGmed), Angular_L (ANG.L), Parietal_Inf_R (IPL.R), SupraMarginal_R (SMG.R), and Postcentral_R (PoCG.R). ReHo values were increased in the Temporal_Pole_Mid_R (TPOsup.R), as well as decreased ReHo in the Insula_R (INS.R), Frontal_Inf_Oper_R (ORBinf.R), Putamen_R (PUT.R), Rolandic_Oper_R (ROL.R), bilateral Cingulum_Post (PCG), bilateral Frontal_Sup_Medial (SFGmed), bilateral anterior cingulate and paracingulate gyri (ACG), and the bilateral precuneus (PCUN). Across the entire brain, there was a decline in the FC between Angular_R and Frontal_Sup_Medial_L.

Conclusion

Alterations in brain regions of female patients with PI involved multiple functional networks, including the default mode network, the salience network, the central executive network, and the limbic network. Reduced coordination between functional networks may be an important mechanism for insomnia and may lead to reduced cognitive function and decision-making ability.

Phenomena of hypo- and hyperconnectivity in basal ganglia-thalamo-cortical circuits linked to major depression: a 7T fMRI study

Major depressive disorder (MDD) typically manifests itself in depressed affect, anhedonia, low energy, and additional symptoms. Despite its high global prevalence, its pathophysiology still gives rise to questions. Current research places alterations in functional connectivity among MDD's most promising biomarkers. However, given the heterogeneity of previous findings, the use of higher-resolution imaging techniques, like ultra-high field (UHF) fMRI (≥7 Tesla, 7T), may offer greater specificity in delineating fundamental impairments. In this study, 7T UHF fMRI scans were conducted on 31 MDD patients and 27 age-gender matched healthy controls to exploratorily contrast cerebral resting-state functional connectivity patterns between both groups. The CONN toolbox was used to generate functional network connectivity (FNC) analysis based on the region of interest (ROI)-to-ROI correlations in order to enable the identification of clusters of significantly different connections. Correction for multiple comparisons was implemented at the cluster level using a false discovery rate (FDR). The analysis revealed three significant clusters differentiating MDD patients and healthy controls. In Clusters 1 and 2, MDD patients exhibited between-network hypoconnectivity in basal ganglia-cortical pathways as well as hyperconnectivity in thalamo-cortical pathways, including several individual ROI-to-ROI connections. In Cluster 3, they showed increased occipital interhemispheric within-network connectivity. These findings suggest that alterations in basal ganglia-thalamo-cortical circuits play a substantial role in the pathophysiology of MDD. Furthermore, they indicate potential MDD-related deficits relating to a combination of perception (vision, audition, and somatosensation) as well as more complex functions, especially social-emotional processing, modulation, and regulation. It is anticipated that these findings might further inform more accurate clinical procedures for addressing MDD.

How does parental rearing patterns of children in upper primary school impact social withdrawal? A mediating effect of emotional regulation

Introduction

The present study endeavors to elucidate the impact of emotional regulation and parental rearing patterns on the social development of children in the upper grades of primary school. A burgeoning body of literature suggests that these factors significantly influence children's social adaptation and emotional well-being, yet a comprehensive examination of these relationships is warranted.

Methods

Employing a cross-sectional design, this investigation utilized the Egna Minnen Beträffande Uppfostran (EMBU), Emotional Regulation Questionnaire for Children (ERQC), and Child Behavioural Issues Scale (CBCL) to assess a sample of 276 pupils across grades 4-6. The selection of these instruments allowed for a multifaceted evaluation of the constructs of interest.

Results

A pronounced disparity in parental rearing practices, emotional regulation capabilities, and levels of social withdrawal was observed among the different grades, with grade 5 exhibiting the most pronounced effects. Parental emotional warmth demonstrated a significant positive correlation with children's emotional regulation abilities, while punitive, rejecting, and preferential behaviors were inversely correlated. The study established that parental rearing practices indirectly influence social withdrawal through the mediating role of children's emotional regulation, underscoring the complexity of this relationship.

Conclusion

The results underscore the salient role of parental rearing and emotional regulation in the social development of children. The study contributes to the existing literature by providing a nuanced understanding of the mechanisms through which parenting styles and emotional competencies interplay to affect social withdrawal. Implications for educational practices and future research directions are discussed.

The impact of acute violent videogame exposure on neurocognitive markers of empathic concern

Research examining the purported association between violent gaming and aggression remains controversial due to concerns related to methodology, unclear neurocognitive mechanisms, and the failure to adequately consider the role of individual differences in susceptibility. To help address these concerns, we used fMRI and an emotional empathy task to examine whether acute and cumulative violent gaming exposure were associated with abnormalities in emotional empathy as a function of trait-empathy. Emotional empathy was targeted given its involvement in regulating not only aggression, but also other important social functions such as compassion and prosocial behaviour. We hypothesized that violent gaming exposure increases the risk of aberrant social behaviour by altering the aversive value of distress cues. Contrary to expectations, neither behavioural ratings nor empathy-related brain activity varied as a function of violent gaming exposure. Notably, however, activation patterns in somatosensory and motor cortices reflected an interaction between violent gaming exposure and trait empathy. Thus, our results are inconsistent with a straightforward relationship between violent gaming exposure and reduced empathy. Furthermore, they highlight the importance of considering both individual differences in susceptibility and other aspects of cognition related to social functioning to best inform public concern regarding safe gaming practices.

Potential association between suicide risk, aggression, impulsivity, and the somatosensory system

Aggression and impulsivity are linked to suicidal behaviors, but their relationship to the suicidal crisis remains unclear. This magnetoencephalography (MEG) study investigated the link between aggression, impulsivity, and resting-state MEG power and connectivity. Four risk groups were enrolled: high-risk (HR; n = 14), who had a recent suicidal crisis; lower-risk (LR; n = 41), who had a history of suicide attempts but no suicide attempt or ideation in the past year; clinical control (CC; n = 38), who had anxiety/mood disorders but no suicidal history; and minimal risk (MR; n = 28), who had no psychiatric/suicidal history. No difference in resting-state MEG power was observed between the groups. Individuals in the HR group with high self-reported aggression and impulsivity scores had reduced MEG power in regions responsible for sensory/emotion regulation vs. those in the HR group with low scores. The HR group also showed downregulated bidirectional glutamatergic feedback between the precuneus (PRE) and insula (INS) compared to the LR, CC, and MR groups. High self-reported impulsivity was linked to reduced PRE to INS feedback, whereas high risk-taking impulsivity was linked to upregulated INS to postcentral gyrus (PCG) and PCG to INS feedback. These preliminary findings suggest that glutamatergic-mediated sensory and emotion-regulation processes may function as potential suicide risk markers.

Exploring brain asymmetry in early-stage Parkinson's disease through functional and structural MRI

OBJECTIVE

This study explores the correlation between asymmetrical brain functional activity, gray matter asymmetry, and the severity of early-stage Parkinson's disease (PD).

METHODS

Ninety-three early-stage PD patients (ePD, H-Y stages 1-2.5) were recruited, divided into 47 mild (ePD-mild, H-Y stages 1-1.5) and 46 moderate (ePD-moderate, H-Y stages 2-2.5) cases, alongside 43 matched healthy controls (HCs). The study employed the Hoehn and Yahr (H-Y) staging system for disease severity assessment and utilized voxel-mirrored homotopic connectivity (VMHC) for analyzing brain functional activity asymmetry. Asymmetry voxel-based morphometry analysis (VBM) was applied to evaluate gray matter asymmetry.

RESULTS

The study found that, relative to HCs, both PD subgroups demonstrated reduced VMHC values in regions including the amygdala, putamen, inferior and middle temporal gyrus, and cerebellum Crus I. The ePD-moderate group also showed decreased VMHC in additional regions such as the postcentral gyrus, lingual gyrus, and superior frontal gyrus, with notably lower VMHC in the superior frontal gyrus compared to the ePD-mild group. A negative correlation was observed between the mean VMHC values in the superior frontal gyrus and H-Y stages, UPDRS, and UPDRS-III scores. No significant asymmetry in gray matter was detected.

CONCLUSIONS

Asymmetrical brain functional activity is a significant characteristic of PD, which exacerbates as the disease severity increases, resembling the dissemination of Lewy bodies across the PD neurological framework. VMHC emerges as a potent tool for characterizing disease severity in early-stage PD.

Aberrant functional connectivity of the globus pallidus in the modulation of the relationship between childhood trauma and major depressive disorder

BACKGROUND

Childhood trauma plays a crucial role in the dysfunctional reward circuitry in major depressive disorder (MDD). We sought to explore the effect of abnormalities in the globus pallidus (GP)-centric reward circuitry on the relationship between childhood trauma and MDD.

METHODS

We conducted seed-based dynamic functional connectivity (dFC) analysis among people with or without MDD and with or without childhood trauma. We explored the relationship between abnormal reward circuitry, childhood trauma, and MDD.

RESULTS

We included 48 people with MDD and childhood trauma, 30 people with MDD without childhood trauma, 57 controls with childhood trauma, and 46 controls without childhood trauma. We found that GP subregions exhibited abnormal dFC with several regions, including the inferior parietal lobe, thalamus, superior frontal gyrus (SFG), and precuneus. Abnormal dFC in these GP subregions showed a significant correlation with childhood trauma. Moderation analysis revealed that the dFC between the anterior GP and SFG, as well as between the anterior GP and the precentral gyrus, modulated the relationship between childhood abuse and MDD severity. We observed a negative correlation between childhood trauma and MDD severity among patients with lower dFC between the anterior GP and SFG, as well as higher dFC between the anterior GP and precentral gyrus. This suggests that reduced dFC between the anterior GP and SFG, along with increased dFC between the anterior GP and precentral gyrus, may attenuate the effect of childhood trauma on MDD severity.

LIMITATIONS

Cross-sectional designs cannot be used to infer causality.

CONCLUSION

Our findings underscore the pivotal role of reward circuitry abnormalities in MDD with childhood trauma. These abnormalities involve various brain regions, including the postcentral gyrus, precentral gyrus, inferior parietal lobe, precuneus, superior frontal gyrus, thalamus, and middle frontal gyrus.

CLINICAL TRIAL REGISTRATION

ChiCTR2300078193.

Association between sleep problems and impulsivity mediated through regional homogeneity abnormalities in male methamphetamine abstainers

Sleep problems and impulsivity frequently occur in methamphetamine (MA) abstainers and are linked to aberrant brain function. However, the interplay between these factors remains poorly understood. This study aimed to investigate the relationship between sleep, impulsivity, and regional homogeneity (ReHo) through mediation analysis in MA abstainers. 46 MA abstainers and 44 healthy controls were included. Impulsivity and sleep problems were evaluated using the Barratt Impulsivity Scale and the Pittsburgh Sleep Quality Scale, respectively. ReHo, indicative of local brain spontaneous neural activity, was assessed using resting-state functional magnetic resonance imaging. Results unveiled correlations between different dimensions of impulsivity and ReHo values in specific brain regions. Motor impulsivity correlated with ReHo values in the left postcentral gyrus and left precentral gyrus, while non-planning impulsivity was only associated with ReHo values in the left precentral gyrus. Additionally, the need for sleep medications correlated with ReHo values in the left precentral gyrus and bilateral postcentral gyrus. Also, the need for sleep medications was positively correlated with cognitive impulsivity and motor impulsivity. Mediation analysis indicated that reduced ReHo values in the left precentral gyrus mediated the association between impulsivity and the need for sleep medications. These findings imply that addressing sleep problems, especially the need for sleep medications, might augment spontaneous neural activity in specific brain regions linked to impulsivity among MA abstainers. This underscores the importance of integrating sleep interventions into comprehensive treatment strategies for MA abstainers.

Mapping the emotional homunculus with fMRI

Emotions are commonly associated with bodily sensations, e.g., boiling with anger when overwhelmed with rage. Studies have shown that emotions are related to specific body parts, suggesting that somatotopically organized cortical regions that commonly respond to somatosensory and motor experiences might be involved in the generation of emotions. We used functional magnetic resonance imaging to investigate whether the subjective feelings of emotion are accompanied by the activation of somatotopically defined sensorimotor brain regions, thus aiming to reconstruct an "emotional homunculus." By defining the convergence of the brain activation patterns evoked by self-generated emotions during scanning onto a sensorimotor map created on participants' tactile and motor brain activity, we showed that all the evoked emotions activated parts of this sensorimotor map, yet with considerable overlap among different emotions. Although we could not find a highly specific segmentation of discrete emotions over sensorimotor regions, our results support an embodied experience of emotions.

Pilot study of circulating cell-free mitochondrial DNA in relation to brain structure in youth bipolar disorder

BACKGROUND

Mitochondrial dysfunction is implicated in the neuropathology of bipolar disorder (BD). Higher circulating cell-free mitochondrial DNA (ccf-mtDNA), generally reflecting poorer mitochondrial health, has been associated with greater symptoms severity in BD. The current study examines the association of serum ccf-mtDNA and brain structure in relation to youth BD. We hypothesized that higher ccf-mtDNA will be associated with measures of lower brain structure, particularly in the BD group.

METHODS

Participants included 40 youth (BD, n = 19; Control group [CG], n = 21; aged 13-20 years). Serum ccf-mtDNA levels were assayed. T1-weighted brain images were acquired using 3T-MRI. Region of interest (ROI) analyses examined prefrontal cortex (PFC) and whole brain gray matter, alongside exploratory vertex-wise analyses. Analyses examined ccf-mtDNA main-effects and ccf-mtDNA-by-diagnosis interaction effects controlling for age, sex, and intracranial volume.

RESULTS

There was no significant difference in ccf-mtDNA levels between BD and CG. In ROI analyses, higher ccf-mtDNA was associated with higher PFC surface area (SA) (β = 0.32 p < 0.001) and PFC volume (β = 0.32 p = 0.002) in the overall sample. In stratified analyses, higher ccf-mtDNA was associated with higher PFC SA within both subgroups (BD: β = 0.39 p = 0.02; CG: β = 0.24 p = 0.045). Higher ccf-mtDNA was associated with higher PFC volume within the BD group (β = 0.39 p = 0.046). In vertex-wise analyses, higher ccf-mtDNA was associated with higher SA and volume in frontal clusters within the overall sample and within the BD group. There were significant ccf-mtDNA-by-diagnosis interactions in three frontal and parietal clusters, whereby higher ccf-mtDNA was associated with higher neurostructural metrics in the BD group but lower neurostructural metrics in CG.

CONCLUSIONS

Contrasting our hypothesis, higher ccf-mtDNA was consistently associated with higher, rather than lower, regional neuralstructural metrics among youth with BD. While this finding may reflect a compensatory mechanism, future repeated-measures prospective studies evaluating the inter-relationship among ccf-mtDNA, mood, and brain structure across developmental epochs and illness stages are warranted.

The Important Role of the Right Dorsolateral Prefrontal Cortex in Conflict Adaptation: A Combined Voxel-Based Morphometry and Continuous Theta Burst Stimulation Study

Humans can flexibly adjust their executive control to resolve conflicts. Conflict adaptation and conflict resolution are crucial aspects of conflict processing. Functional neuroimaging studies have associated the dorsolateral prefrontal cortex (DLPFC) with conflict processing, but its causal role remains somewhat controversial. Moreover, the neuroanatomical basis of conflict processing has not been thoroughly examined. In this study, the Stroop task, a well-established measure of conflict, was employed to investigate (1) the neuroanatomical basis of conflict resolution and conflict adaptation with the voxel-based morphometry analysis, (2) the causal role of DLPFC in conflict processing with the application of the continuous theta burst stimulation to DLPFC. The results revealed that the Stroop effect was correlated to the gray matter volume of the precuneus, postcentral gyrus, and cerebellum, and the congruency sequence effect was correlated to the gray matter volume of superior frontal gyrus, postcentral gyrus, and lobule paracentral gyrus. These findings indicate the neuroanatomical basis of conflict resolution and adaptation. In addition, the continuous theta burst stimulation over the right DLPFC resulted in a significant reduction in the Stroop effect of RT after congruent trials compared with vertex stimulation and a significant increase in the Stroop effect of accuracy rate after incongruent trials than congruent trials, demonstrating the causal role of right DLPFC in conflict adaptation. Moreover, the DLPFC stimulation did not affect the Stroop effect of RT and accuracy rate. Overall, our study offers further insights into the neural mechanisms underlying conflict resolution and adaptation.

Interventions targeting emotion regulation: A systematic umbrella review

BACKGROUND

Emotion dysregulation (ED), the difficulty in modulating which emotions are felt, and when and how they are expressed or experienced, has been implicated in an array of psychological disorders. Despite potentially different manifestations depending on the disorder, this symptom is emerging as a transdiagnostic construct that can and should be targeted early, given the associations with various maladaptive behaviors as early as childhood and adolescence. As such, our goal was to investigate the psychotherapeutic interventions used to address ED and gauge their effectiveness, safety, and potential mechanisms across various populations.

METHODS

This umbrella systematic review, pre-registered under PROSPERO (registration: CRD42023411452), consolidates evidence from systematic reviews and meta-analyses on psychotherapeutic interventions targeting ED, in accordance with PRISMA guidelines.

RESULTS

Our synthesis of quantitative and qualitative evidence from 21 systematic reviews (including 11 meta-analyses) points-with moderate overall risk of bias-to the effectiveness of Dialectical Behavior Therapy and Cognitive Behavioral Therapy in reducing ED in a wide range of adult transdiagnostic psychiatric patients and healthy participants. Similar results have emerged in other less extensively researched methods as well. However, results on adolescents and children are sparse, highlighting the need for additional research to tailor these interventions to the unique challenges of ED in younger populations with diverse externalizing and internalizing disorders.

CONCLUSIONS

These demonstrated transdiagnostic advantages of psychotherapy for ED underscore the potential for specifically designed interventions that address this issue directly, particularly for high-risk individuals. In these individuals, early interventions targeting transdiagnostic core dimensions may mitigate the emergence of full-blown disorders. Future research on the mediating factors, the durability of intervention effects, and the exploration of understudied interventions and populations may enhance prevention and treatment efficiency, enhancing the quality of life for those affected by varied manifestations of ED.

Vibration-reduced anxiety-like behavior relies on ameliorating abnormalities of the somatosensory cortex and medial prefrontal cortex

Tibetan singing bowls emit low-frequency sounds and produce perceptible harmonic tones and vibrations through manual tapping. The sounds the singing bowls produce have been shown to enhance relaxation and reduce anxiety. However, the underlying mechanism remains unclear. In this study, we used chronic restraint stress or sleep deprivation to establish mouse models of anxiety that exhibit anxiety-like behaviors. We then supplied treatment with singing bowls in a bottomless cage placed on the top of a cushion. We found that unlike in humans, the combination of harmonic tones and vibrations did not improve anxiety-like behaviors in mice, while individual vibration components did. Additionally, the vibration of singing bowls increased the level of N-methyl-D-aspartate receptor 1 in the somatosensory cortex and prefrontal cortex of the mice, decreased the level of γ-aminobutyric acid A (GABA) receptor α 1 subtype, reduced the level of CaMKII in the prefrontal cortex, and increased the number of GABAergic interneurons. At the same time, electrophysiological tests showed that the vibration of singing bowls significantly reduced the abnormal low-frequency gamma oscillation peak frequency in the medial prefrontal cortex caused by stress restraint pressure and sleep deprivation. Results from this study indicate that the vibration of singing bowls can alleviate anxiety-like behaviors by reducing abnormal molecular and electrophysiological events in somatosensory and medial prefrontal cortex.

Mapping Early Brain-Body Interactions: Associations of Fetal Heart Rate Variation with Newborn Brainstem, Hypothalamic, and Dorsal Anterior Cingulate Cortex Functional Connectivity

The autonomic nervous system (ANS) regulates the body's physiology, including cardiovascular function. As the ANS develops during the second to third trimester, fetal heart rate variability (HRV) increases while fetal heart rate (HR) decreases. In this way, fetal HR and HRV provide an index of fetal ANS development and future neurobehavioral regulation. Fetal HR and HRV have been associated with child language ability and psychomotor development behavior in toddlerhood. However, their associations with postbirth autonomic brain systems, such as the brainstem, hypothalamus, and dorsal anterior cingulate cortex (dACC), have yet to be investigated even though brain pathways involved in autonomic regulation are well established in older individuals. We assessed whether fetal HR and HRV were associated with the brainstem, hypothalamic, and dACC functional connectivity in newborns. Data were obtained from 60 pregnant individuals (ages 14-42) at 24-27 and 34-37 weeks of gestation using a fetal actocardiograph to generate fetal HR and HRV. During natural sleep, their infants (38 males and 22 females) underwent a fMRI scan between 40 and 46 weeks of postmenstrual age. Our findings relate fetal heart indices to brainstem, hypothalamic, and dACC connectivity and reveal connections with widespread brain regions that may support behavioral and emotional regulation. We demonstrated the basic physiologic association between fetal HR indices and lower- and higher-order brain regions involved in regulatory processes. This work provides the foundation for future behavioral or physiological regulation research in fetuses and infants.

From Connectivity to Controllability: Unraveling the Brain Biomarkers of Major Depressive Disorder

Major Depressive Disorder (MDD) is a significant neurological condition associated with aberrations in brain functional networks. Traditional studies have predominantly analyzed these from a network topology perspective. However, given the brain's dynamic and complex nature, exploring its mechanisms from a network control standpoint provides a fresh and insightful framework. This research investigates the integration of network controllability and machine learning to pinpoint essential biomarkers for MDD using functional magnetic resonance imaging (fMRI) data. By employing network controllability methods, we identify crucial brain regions that are instrumental in facilitating transitions between brain states. These regions demonstrate the brain's ability to navigate various functional states, emphasizing the utility of network controllability metrics as potential biomarkers. Furthermore, these metrics elucidate the complex dynamics of MDD and support the development of precision medicine strategies that incorporate machine learning to improve the precision of diagnostics and the efficacy of treatments. This study underscores the value of merging machine learning with network neuroscience to craft personalized interventions that align with the unique pathological profiles of individuals, ultimately enhancing the management and treatment of MDD.

Abnormal degree centrality as a potential imaging biomarker for ischemic stroke: A resting-state functional magnetic resonance imaging study

OBJECTIVE

To explore degree centrality (DC) abnormalities in ischemic stroke patients and determine whether these abnormalities have potential value in understanding the pathological mechanisms of ischemic stroke patients.

METHODS

Sixteen ischemic stroke patients and 22 healthy controls (HCs) underwent resting state functional magnetic resonance imaging (rs-fMRI) scanning, and the resulting data were subjected to DC analysis. Then we conducted a correlation analysis between DC values and neuropsychological test scores, including Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE). Finally, extracted the abnormal DC values of brain regions and defined them as features for support vector machine (SVM) analysis.

RESULTS

Compared with HCs, ischemic stroke patients showed increased DC in the bilateral supplementary motor area, and median cingulate and paracingulate gyri and decreased DC in the left postcentral gyrus, right calcarine fissure and surrounding cortex, lingual gyrus, and orbital parts of the right superior frontal gyrus and bilateral cuneus. Correlation analyses revealed that DC values in the right lingual gyrus, calcarine fissure and surrounding cortex, and orbital parts of the right superior frontal gyrus were positively correlated with the MMSE scores. The SVM classification of the DC values achieved an area under the curve (AUC) of 0.93, an accuracy of 89.47%.

CONCLUSION

Our research results indicate that ischemic stroke patients exhibit abnormalities in the global connectivity mechanisms and patterns of the brain network. These abnormal changes may provide neuroimaging evidence for stroke-related motor, visual, and cognitive impairments, contribute to a deeper comprehension of the underlying pathophysiological mechanisms implicated in ischemic stroke.

Functional alterations of the brain default mode network and somatosensory system in trigeminal neuralgia

Mapping the localization of the functional brain regions in trigeminal neuralgia (TN) patients is still lacking. The study aimed to explore the functional brain alterations and influencing factors in TN patients using functional brain imaging techniques. All participants underwent functional brain imaging to collect resting-state brain activity. The significant differences in regional homogeneity (ReHo) and amplitude of low frequency (ALFF) between the TN and control groups were calculated. After familywise error (FWE) correction, the differential brain regions in ReHo values between the two groups were mainly located in bilateral middle frontal gyrus, bilateral inferior cerebellum, right superior orbital frontal gyrus, right postcentral gyrus, left inferior temporal gyrus, left middle temporal gyrus, and left gyrus rectus. The differential brain regions in ALFF values between the two groups were mainly located in the left triangular inferior frontal gyrus, left supplementary motor area, right supramarginal gyrus, and right middle frontal gyrus. With the functional impairment of the central pain area, the active areas controlling memory and emotion also change during the progression of TN. There may be different central mechanisms in TN patients of different sexes, affected sides, and degrees of nerve damage. The exact central mechanisms remain to be elucidated.

Resting-state activity and functional connectivity of insula and postcentral gyrus related to psychological resilience in female depressed patients: A preliminary study

BACKGROUND

Psychological resilience is a protective factor of depression. However, the neuroimaging characteristics of the relationship between psychological resilience and brain imaging in depression are not very clear. Our objectives were to explore the brain functional imaging characteristics of different levels of resilience in female patients with depression.

METHODS

Resting-state functional magnetic resonance imaging (rs-fMRI) was performed on 58 female depressed patients. According to the resilience score, participants were divided into three groups: Low resilience (Low-res), Medium resilience (Med-res) and High resilience (High-res). We compared the differences in the amplitude of low-frequency fluctuations (ALFF) and functional connectivity (FC) among the three groups and correlated psychological resilience with ALFF and FC.

RESULTS

According to ALFF, there was a higher activation in RI and RPG in the High-res compared with Med-res and Low-res, but no significant differences between Med-res and Low-res. The FC between the RPG and supramarginal gyrus (SG) in the High-res was significantly stronger than that in the Med-res and the Low-res, and the FC of the Med-res is stronger than that of the Low-res. Both ALFF and FC were positively correlated with the score of resilience.

LIMITATIONS

The sample size of this study was relatively small and it lacked healthy controls. The results of this study could be considered preliminary.

CONCLUSIONS

Among female patients with depression, patients with higher psychological resilience had higher resting state activation in the RI and RPG and had a stronger interaction between the RPG and the SG.

Differences in Cortical Activation During Dorsiflexion and Plantarflexion in Chronic Ankle Instability: A Task-fMRI Study

BACKGROUND

Chronic ankle instability is a common sports injury that often presents with increased plantarflexion and restricted dorsiflexion. The cumulative effect of peripheral injuries may induce neuroplasticity in the central nervous system. However, the relationship between dorsiflexion or plantarflexion and the central nervous system in patients with chronic ankle instability remains unknown.

QUESTIONS/PURPOSES

(1) Is there a difference in region and voxel (volume pixel) of cortical activation during plantarflexion and dorsiflexion between patients with chronic ankle instability and a control group with normal ankle function? (2) Is there a correlation between activation of sensorimotor-related brain regions and three clinical measurement scales of ankle function and disease severity in patients with chronic ankle instability?

METHODS

Between December 2020 and May 2022, we treated 400 patients who had chronic ankle instability. Ten percent (40 patients; mean ± standard deviation age 29 ± 7 years; 17 male patients) were randomly selected to participate in this study. We recruited 42 volunteers with normal ankle function (mean age 28 ± 5 years; 21 male participants) matched by age and education level. A total of 2.5% (1 of 40) of patients with bilateral chronic ankle instability and 30% (12 of 40) with left-sided chronic ankle injury did not meet our inclusion criteria and were excluded from the study. The control group underwent MRI with good image quality. Finally, 27 patients with chronic ankle instability (mean age 26 ± 5 years; 10 male patients) and 42 participants with normal ankle function were enrolled. Ankle function and disease severity were assessed using three clinical scales: the Cumberland Ankle Instability Tool, Karlsson-Peterson Ankle Function Score, and the American Orthopedic Foot and Ankle Society Score. A uniplanar and nonweightbearing ankle dorsiflexion-plantarflexion paradigm (a recognized model or pattern) was performed using a short-block design during the functional MRI scan. This experimental design included a series of on-off periods consisting of movement and a rest period. From 15° of plantarflexion to 15° of dorsiflexion, the manipulator allowed 30° of ankle rotation. The cerebral excitability patterns between patients with chronic ankle instability and controls were analyzed using t-tests. We retained voxels with p values less than 0.05 in a voxel-level family-wise error correction. Clusters with voxel numbers greater than 10 were retained. The Cohen d coefficient was used to calculate between-group effect sizes. Spearman analysis was performed to explore the correlation between activation regions and the three clinical assessment scales.

RESULTS

In the patient group, cortical activation was greater during plantarflexion than during dorsiflexion, which was different from that in the control group. The between-group comparison showed that patients with chronic ankle instability had reduced activation in the ipsilateral precuneus (cluster size = 35 voxels [95% CI -0.23 to 0.07]; p < 0.001) during dorsiflexion, whereas during plantarflexion, chronic ankle instability caused increased activation in the ipsilateral superior temporal gyrus (cluster size = 90 voxels [95% CI -0.73 to -0.13]; p < 0.001), precuneus (cluster size = 18 voxels [95% CI -0.56 to -0.19]; p < 0.001), supplementary motor area (cluster size = 57 voxels [95% CI -0.31 to 0.00]; p < 0.001), superior frontal gyrus (cluster size = 43 voxels [95% CI -0.82 to -0.29]; p < 0.001), medial part of the superior frontal gyrus (cluster size = 39 voxels [95% CI 0.41 to 0.78]; p < 0.001), and contralateral postcentral gyrus (cluster size = 100 voxels [95% CI -0.32 to 0.02]; p < 0.001). Patients with chronic ankle instability showed a large effect size compared with controls (Cohen d > 0.8). During plantarflexion, the number of activated voxels in the supplementary motor area had a modest, positive correlation with the Karlsson-Peterson Ankle Function Score (r = 0.52; p = 0.01), and the number of activated voxels in the primary motor cortex (M1) and primary sensory cortex (S1) had a weak, positive correlation with the American Orthopedic Foot and Ankle Society Score in patients with chronic ankle instability (M1: r = 0.45; p = 0.02, S1: r = 0.49; p = 0.01).

CONCLUSION

Compared with volunteers with normal ankle function, patients with chronic ankle instability had increased cortical activation during plantarflexion and decreased cortical activation during dorsiflexion. We analyzed the central neural mechanisms of chronic ankle instability in patients with sports injuries and provided a theoretical basis for the development of new central and peripheral interventions in the future.

CLINICAL RELEVANCE

Because there was a positive correlation between the neural activity in sensorimotor-related regions during plantarflexion and clinical severity, clinicians might one day be able to help patients who have chronic ankle instability with neuromuscular rehabilitation by applying electrical stimulation to specific targets (such as S1M1 and the supplementary motor area) or by increasing activation of sensorimotor neurons through ankle movement.

Abnormal amplitude of low-frequency fluctuations associated with sleep efficiency in major depressive disorder

BACKGROUND

Sleep disturbance is one of the most frequent somatic symptoms in major depressive disorder (MDD), but the neural mechanisms behind it are not well understood. Sleep efficiency (SE) is a good indicator of early awakening and difficulty falling asleep in MDD patients. Our study aimed to investigate the relationship between sleep efficiency and brain function in MDD patients.

METHODS

We recruited 131 MDD patients from the Fourth People's Hospital in Hefei, and 71 well-matched healthy controls who were enrolled from the community. All subjects underwent resting-state functional MRI. Brain function was measured using the fractional amplitude of low-frequency fluctuation (fALFF), sleep efficiency was objectively measured by polysomnography (PSG), and clinical scales were used to evaluate depressive symptoms and sleep status. Multivariate regression analysis was performed to assess the relationship between the amplitude of the low frequency fluctuation fraction and sleep efficiency.

RESULT

Three brain regions with relevance to sleep efficiency in MDD patients were found: inferior occipital gyrus (Number of voxels = 25, peak MNI coordinate x/y/z = -42/-81/-6, Peak intensity = 4.3148), middle occipital gyrus (Number of voxels = 55, peak MNI coordinate x/y/z = -30/-78/18, Peak intensity = 5.111), and postcentral gyrus (Number of voxels = 26, peak MNI coordinate x/y/z = -27/-33/60, Peak intensity = 4.1263). But there was no significant relationship between fALFF and SE in the healthy controls.

CONCLUSION

The reduced sleep efficiency in MDD may be related to their lower neural activity in the inferior occipital gyrus, middle occipital gyrus, and postcentral gyrus. The findings may provide a potential neuroimaging basis for the clinical intervention in patients with major depressive disorder with sleep disturbances.

Persistence of amygdala hyperactivity to subliminal negative emotion processing in the long-term course of depression

Biased emotion processing has been suggested to underlie the etiology and maintenance of depression. Neuroimaging studies have shown mood-congruent alterations in amygdala activity in patients with acute depression, even during early, automatic stages of emotion processing. However, due to a lack of prospective studies over periods longer than 8 weeks, it is unclear whether these neurofunctional abnormalities represent a persistent correlate of depression even in remission. In this prospective case-control study, we aimed to examine brain functional correlates of automatic emotion processing in the long-term course of depression. In a naturalistic design, n = 57 patients with acute major depressive disorder (MDD) and n = 37 healthy controls (HC) were assessed with functional magnetic resonance imaging (fMRI) at baseline and after 2 years. Patients were divided into two subgroups according to their course of illness during the study period (n = 37 relapse, n = 20 no-relapse). During fMRI, participants underwent an affective priming task that assessed emotion processing of subliminally presented sad and happy compared to neutral face stimuli. A group × time × condition (3 × 2 × 2) ANOVA was performed for the amygdala as region-of-interest (ROI). At baseline, there was a significant group × condition interaction, resulting from amygdala hyperactivity to sad primes in patients with MDD compared to HC, whereas no difference between groups emerged for happy primes. In both patient subgroups, amygdala hyperactivity to sad primes persisted after 2 years, regardless of relapse or remission at follow-up. The results suggest that amygdala hyperactivity during automatic processing of negative stimuli persists during remission and represents a trait rather than a state marker of depression. Enduring neurofunctional abnormalities may reflect a consequence of or a vulnerability to depression.

Dynamic brain communication underwriting face pareidolia

Face pareidolia is a tendency to seeing faces in nonface images that reflects high tuning to a face scheme. Yet, studies of the brain networks underwriting face pareidolia are scarce. Here, we examined the time course and dynamic topography of gamma oscillatory neuromagnetic activity while administering a task with nonface images resembling a face. Images were presented either with canonical orientation or with display inversion that heavily impedes face pareidolia. At early processing stages, the peaks in gamma activity (40 to 45 Hz) to images either triggering or not face pareidolia originate mainly from the right medioventral and lateral occipital cortices, rostral and caudal cuneus gyri, and medial superior occipital gyrus. Yet, the difference occurred at later processing stages in the high-frequency range of 80 to 85 Hz over a set of the areas constituting the social brain. The findings speak rather for a relatively late neural network playing a key role in face pareidolia. Strikingly, a cutting-edge analysis of brain connectivity unfolding over time reveals mutual feedforward and feedback intra- and interhemispheric communication not only within the social brain but also within the extended large-scale network of down- and upstream regions. In particular, the superior temporal sulcus and insula strongly engage in communication with other brain regions either as signal transmitters or recipients throughout the whole processing of face-pareidolia images.

Aberrant occlusal sensitivity in adults with increased somatosensory amplification: a case-control study

OBJECTIVES

Occlusal sensitivity (OS)-the ability to detect fine objects between opposing teeth-mainly relies on the activity of mechanoreceptors located in the periodontal ligament. We tested whether somatosensory amplification (SSA)-the tendency to perceive normal somatic sensations as being intense, noxious, and disturbing, which plays a critical role in hypervigilance-affects OS.

MATERIALS AND METHODS

We measured OS in 66 adults divided into three groups based on their SSA scores (LowSSA, Intermediate - IntSSA, HighSSA) by asking them to bite on aluminum foils (8 to 72 μm thick) and a sham foil, and report whether they felt each foil. We performed 20 trials for each thickness and sham condition (each participant was tested 120 times), and compared the frequency of correct answers (%correct) among groups after adjusting for participants' trait anxiety, depression, self-reported oral behaviors, and masseter cross-sectional area.

RESULTS

%correct was affected by the interaction Foil Thickness-by-SSA (p = 0.007). When tested with the 8 μm foil, the HighSSA group had a lower %correct than the IntSSA (contrast estimate [95% CI]: -14.2 [-25.8 - -2.6]; p = 0.012) and the LowSSA groups (-19.1 [-31.5 - -6.6]; p = 0.001). Similarly, with the 24 μm foil, the HighSSA group had a lower %correct compared to the IntSSA (-12.4 [-24.8-0.1]; p = 0.048) and the LowSSA groups (-10.8 [-22.5-0.8]; p = 0.073).

CONCLUSION

Individuals with high SSA present with an aberrant occlusal sensitivity.

CLINICAL RELEVANCE

Our findings provide novel insights into the relationship between occlusal perception and psychological factors, which may influence an individual's ability to adapt to dental work.

Suppression of Cofilin function in the somatosensory cortex alters social contact behavior in the BTBR mouse inbred line

Sensory differences are a core feature of autism spectrum disorders (ASD) and are predictive of other ASD core symptoms such as social difficulties. However, the neurobiological substrate underlying the functional relationship between sensory and social functioning is poorly understood. Here, we examined whether misregulation of structural plasticity in the somatosensory cortex modulates aberrant social functioning in BTBR mice, a mouse model for autism spectrum disorder-like phenotypes. By locally expressing a dominant-negative form of Cofilin (CofilinS3D; a key regulator of synaptic structure) in the somatosensory cortex, we tested whether somatosensory suppression of Cofilin activity alters social functioning in BTBR mice. Somatosensory Cofilin suppression altered social contact and nest-hide behavior of BTBR mice in a social colony, assessed for seven consecutive days. Subsequent behavioral testing revealed that altered social functioning is related to altered tactile sensory perception; CofilinS3D-treated BTBR mice showed a time-dependent difference in the sensory bedding preference task. These findings show that Cofilin suppression in the somatosensory cortex alters social functioning in BTBR mice and that this is associated with tactile sensory processing, a critical indicator of somatosensory functioning.

Altered spontaneous neurological activity in methamphetamine use disorders and its association with cognitive function

BACKGROUND

Methamphetamine (MA) is a widely used and detrimental drug, yet the precise mechanisms by which MA affects cognitive function remain unclear. This study aims to investigate the relationship between cognitive function and brain functional imaging in individuals with MA use disorder (MUD).

METHODS

This study involved 45 patients diagnosed with MUD and 43 healthy controls (HC). Cognitive function assessment utilized the MATRICS Consensus Cognitive Battery, and functional data were acquired using a 3.0 Tesla magnetic resonance imaging scanner.

RESULTS

The MUD group exhibited lower regional homogeneity (ReHo) values in the bilateral postcentral, the left superior temporal, and the left lingual regions compared to the HC group. Additionally, the MUD group displayed higher amplitude of low-frequency fluctuation (ALFF) values in the bilateral fusiform and the left putamen compared to the HC group, along with lower ALFF values in the bilateral postcentral cortices and the left middle cingulate cortex compared to the HC group (all p < 0.05, with false discovery rate corrected). Linear regression analysis revealed a positive correlation between the ReHo value in the right postcentral cortex and the neuropsychology assessment battery-mazes test (p = 0.014). Furthermore, the ALFF value in the left putamen showed negative correlations with the scores of the digit-symbol coding test (p = 0.027), continuous performance test (p = 0.037), and battery-mazes test (p = 0.024).

CONCLUSION

Patients with MUD exhibit altered brain spontaneous neurological activities, and the intensity of spontaneous neurological activity in the left putamen is strongly associated with cognitive function.

OPM-MEG Measuring Phase Synchronization on Source Time Series: Application in Rhythmic Median Nerve Stimulation

The magnetoencephalogram (MEG) based on array optically pumped magnetometers (OPMs) has the potential of replacing conventional cryogenic superconducting quantum interference device. Phase synchronization is a common method for measuring brain oscillations and functional connectivity. Verifying the feasibility and fidelity of OPM-MEG in measuring phase synchronization will help its widespread application in the study of aforementioned neural mechanisms. The analysis method on source-level time series can weaken the influence of instantaneous field spread effect. In this paper, the OPM-MEG was used for measuring the evoked responses of 20Hz rhythmic and arrhythmic median nerve stimulation, and the inter-trial phase synchronization (ITPS) and inter-reginal phase synchronization (IRPS) of primary somatosensory cortex (SI) and secondary somatosensory cortex (SII) were analysed. The results find that under rhythmic condition, the evoked responses of SI and SII show continuous oscillations and the effect of resetting phase. The values of ITPS and IRPS significantly increase at the stimulation frequency of 20Hz and its harmonic of 40Hz, whereas the arrhythmic stimulation does not exhibit this phenomenon. Moreover, in the initial stage of stimulation, the ITPS and IRPS values are significantly higher at Mu rhythm in the rhythmic condition compared to arrhythmic. In conclusion, the results demonstrate the ability of OPM-MEG in measuring phase pattern and functional connectivity on source-level, and may also prove beneficial for the study on the mechanism of rhythmic stimulation therapy for rehabilitation.

Involvement of primary somatosensory cortex in motor learning and task execution

The primary somatosensory cortex (S1) is responsible for processing information related to tactile stimulation, motor learning and control. Despite its significance, the connection between S1 and the primary motor cortex (M1), as well as its role in motor learning, remains a topic of ongoing exploration. In the present study, we silenced S1 by the GABA receptor agonist muscimol to study the potential roles of S1 in motor learning and task execution. Our results show that the inhibition of S1 leads to an immediate impairment in performance during the training session and also a substantial reduction in performance improvement during post-test session on the subsequent day. To understand the underlying mechanism, we used intravital two-photon imaging to investigate the dynamics of dendritic spines of layer V pyramidal neurons and the calcium activities of pyramidal neurons in M1 after inhibition of S1. Notably, S1 inhibition reduces motor training-induced spine formation and facilitates the elimination of existing spines of layer V pyramidal neurons in M1. The calcium activities in M1 exhibit a significant decrease during both resting and running periods following S1 inhibition. Furthermore, inhibition of S1, but not M1, significantly impairs the execution of the acquired motor task in the well-trained animals. Together, these findings reveal that S1 plays important roles in motor learning and task execution.

Functional connectivity patterns are altered by low back pain and cause different responses to sham and real dry needling therapies: a systematic review of fMRI studies

BACKGROUND

There is a relationship between low back pain (LBP) and central nervous system dysfunction. Needling therapies (e.g. acupuncture, dry needling) are proposed to impact the nervous system, however their specific influence is unclear.

PURPOSE

Determine how needling therapies alter functional connectivity and LBP as measured by functional magnetic resonance imaging (fMRI).

METHODS

Databases were searched following PRISMA guidelines. Studies using fMRI on individuals with LBP receiving dry needling or acupuncture compared to control or sham treatments were included.

RESULTS

Eight studies were included, all of which used acupuncture. The quality of studies ranged from good (n = 6) to excellent (n = 2). After acupuncture, individuals with LBP demonstrated significant functional connectivity changes across several networks, notably the salience, somatomotor, default mode network (DMN) and limbic networks. A meta-analysis demonstrated evidence of no effect to potential small effect of acupuncture in reducing LBP (SMD -0.28; 95% CI: -0.70, 0.13).

CONCLUSION

Needling therapies, like acupuncture, may have a central effect on patients beyond the local tissue effects, reducing patients' pain and disability due to alterations in neural processing, including the DMN, and potentially other central nervous system effects. The meta-analysis should be interpreted with caution due to the narrow focus and confined sample used.

Homotopic functional connectivity disruptions in schizophrenia and their associated gene expression

It has been revealed that abnormal voxel-mirrored homotopic connectivity (VMHC) is present in patients with schizophrenia, yet there are inconsistencies in the relevant findings. Moreover, little is known about their association with brain gene expression profiles. In this study, transcription-neuroimaging association analyses using gene expression data from Allen Human Brain Atlas and case-control VMHC differences from both the discovery (meta-analysis, including 9 studies with a total of 386 patients and 357 controls) and replication (separate group-level comparisons within two datasets, including a total of 258 patients and 287 controls) phases were performed to identify genes associated with VMHC alterations. Enrichment analyses were conducted to characterize the biological functions and specific expression of identified genes, and Neurosynth decoding analysis was performed to examine the correlation between cognitive-related processes and VMHC alterations in schizophrenia. In the discovery and replication phases, patients with schizophrenia exhibited consistent VMHC changes compared to controls, which were correlated with a series of cognitive-related processes; meta-regression analysis revealed that illness duration was negatively correlated with VMHC abnormalities in the cerebellum and postcentral/precentral gyrus. The abnormal VMHC patterns were stably correlated with 1287 genes enriched for fundamental biological processes like regulation of cell communication, nervous system development, and cell communication. In addition, these genes were overexpressed in astrocytes and immune cells, enriched in extensive cortical regions and wide developmental time windows. The present findings may contribute to a more comprehensive understanding of the molecular mechanisms underlying VMHC alterations in patients with schizophrenia.

Shared and distinctive neural substrates of generalized anxiety disorder with or without depressive symptoms and their roles in prognostic prediction

BACKGROUND

The neurophysiological mechanisms underlying generalized anxiety disorder (GAD) with or without depressive symptoms are obscure. This study aimed to uncover them and assess their predictive value for treatment response.

METHODS

We enrolled 98 GAD patients [58 (age: 33.22 ± 10.23 years old, males/females: 25/33) with and 40 (age: 33.65 ± 10.49 years old, males/females: 14/26) without depressive symptoms] and 54 healthy controls (HCs, age: 32.28 ± 10.56 years old, males/females: 21/33). Patients underwent clinical assessments and resting-state functional MRI (rs-fMRI) at baseline and after 4-week treatment with paroxetine, while HCs underwent rs-fMRI at baseline only. Regional homogeneity (ReHo) was employed to measure intrinsic brain activity. We compared ReHo in patients to HCs and examined changes in ReHo within the patient groups after treatment. Support vector regression (SVR) analyses were conducted separately for each patient group to predict the patients' treatment response.

RESULTS

Both patient groups exhibited higher ReHo in the middle/superior frontal gyrus decreased ReHo in different brain regions compared to HCs. Furthermore, differences in ReHo were detected between the two patient groups. After treatment, the patient groups displayed distinct ReHo change patterns. By utilizing SVR based on baseline abnormal ReHo, we effectively predicted treatment response of patients (p-value for correlation < 0.05).

LIMITATIONS

The dropout rate was relatively high.

CONCLUSIONS

This study identified shared and unique neural substrates in GAD patients with or without depressive symptoms, potentially serving as biomarkers for treatment response prediction. Comorbid depressive symptoms were associated with differences in disease manifestation and treatment response compared to pure GAD cases.

Interpersonal neural synchronization during social interactions in close relationships: A systematic review and meta-analysis of fNIRS hyperscanning studies

In recent years, researchers have used hyperscanning techniques to explore how brains interact during various human activities. These studies have revealed a phenomenon called interpersonal neural synchronization (INS), but little research has focused on the overall effect of INS in close relationships. To address this gap, this study aims to synthesize and analyze the existing literature on INS during social interactions in close relationships. We conducted a meta-analysis of 17 functional near-infrared spectroscopy (fNIRS) hyperscanning studies involving 1149 dyads participants, including romantic couples and parent-child dyads. The results revealed robust and consistent INS in the frontal, temporal, and parietal regions of the brain and found similar INS patterns in couples and parent-child studies, providing solid empirical evidence for the attachment theory. Moreover, the age of children and brain areas were significant predictors of the effect size in parent-child research. The developmental stage of children and the mismatched development of brain structures might be the crucial factors for the difference in neural performance in social and cognitive behaviors in parent-child dyads.

Neurobehavioral deficits, histoarchitectural alterations, parvalbumin neuronal damage and glial activation in the brain of male Wistar rat exposed to Landfill leachate

Concerns about inappropriate disposal of waste into unsanitary municipal solid waste landfills around the world have been on the increase, and this poses a public health challenge due to leachate production. The neurotoxic effect of Gwagwalada landfill leachate (GLL) was investigated in male adult Wistar rats. Rats were exposed to a 10% concentration of GLL for 21 days. The control group received tap water for the same period of the experiment. Our results showed that neurobehavior, absolute body and brain weights and brain histomorphology as well as parvalbumin interneurons were severely altered, with consequent astrogliosis and microgliosis after 21 days of administrating GLL. Specifically, there was severe loss and shrinkage of Purkinje cells, with their nucleus, and severe diffused vacuolations of the white matter tract of GLL-exposed rat brains. There was severe cell loss in the granular layer of the cerebellum resulting in a reduced thickness of the layer. Also, there was severe loss of dendritic arborization of the Purkinje cells in GLL-exposed rat brains, and damage as well as reduced populations of parvalbumin-containing fast-spiking GABAergic interneurons in various regions of the brain. In conclusion, data from the present study demonstrated the detrimental effects of Gwagwalada landfill leachate on the brain which may be implicated in neuropsychological conditions.

Influence of transient emotional episodes on affective and cognitive theory of mind

Our emotions may influence how we interact with others. Previous studies have shown an important role of emotion induction in generating empathic reactions towards others' affect. However, it remains unclear whether (and to which extent) our own emotions can influence the ability to infer people's mental states, a process associated with Theory of Mind (ToM) and implicated in the representation of both cognitive (e.g. beliefs and intentions) and affective conditions. We engaged 59 participants in two emotion-induction experiments where they saw joyful, neutral and fearful clips. Subsequently, they were asked to infer other individuals' joy, fear (affective ToM) or beliefs (cognitive ToM) from verbal scenarios. Using functional magnetic resonance imaging, we found that brain activity in the superior temporal gyrus, precuneus and sensorimotor cortices were modulated by the preceding emotional induction, with lower response when the to-be-inferred emotion was incongruent with the one induced in the observer (affective ToM). Instead, we found no effect of emotion induction on the appraisal of people's beliefs (cognitive ToM). These findings are consistent with embodied accounts of affective ToM, whereby our own emotions alter the engagement of key brain regions for social cognition, depending on the compatibility between one's own and others' affect.