Differences In Functional Connectivity Research Articles

Thalamic Contributions to Functional Circuitry in Preclinical Alzheimer’s Disease

AbstractBackgroundThalamic nuclei are heterogeneously impacted by Alzheimer’s disease (AD) pathology. The anterior thalamus shows tau deposition early on in AD, while other nuclei, such as the mediodorsal (MD) thalamus are spared by tau until much later in the disease process (Braak and Braak, 1991). Furthermore, anterior and MD thalamus have dissociable roles in memory performance – the anterior has a greater role in recollective memory, while the MD plays a role in familiarity. Additionally, the anterior thalamus has direct anatomical links to brain regions implicated in poor short‐term memory performance in AD, while MD thalamus connectivity is primarily to regions spared of AD pathology until late. We sought to identify differences in functional connectivity between the anterior and MD thalamus in amyloid negative and positive individuals.MethodWe examined resting‐state functional MRI data from the A4 study (n = 569), including 254 healthy controls and 315 individuals with preclinical AD based on amyloid SUVR>1.14 (Table 1). We assessed functional connectivity of anterior and MD thalamus to the whole brain using 2mm radius spherical seeds at the center of mass of Morel atlas nuclei. All results were covaried for age, sex, handedness, and years of education.ResultsAnterior thalamic activity was positively correlated with parahippocampal gyrus, fusiform, and insula, and negatively with the striatum and thalamus. MD thalamic activity was positively correlated with the amygdala, ventral striatum, and anterior cingulate, and negatively correlated to the superior temporal gyrus and regions of the parieto‐occipital lobe. In preclinical AD, compared with HCs, the positive correlations in either thalamic nuclei were lost.ConclusionThe thalamic functional connectivity observed agrees with preexisting literature dissociating structures related to the anterior and MD thalamus. Our results provide a basis for further exploration of thalamic nuclei to AD‐involved functional networks, as well as future analysis of the observed connectivity measures to cognition.

Thalamic Contributions to Functional Circuitry in Preclinical Alzheimer’s Disease

AbstractBackgroundThalamic nuclei are heterogeneously impacted by Alzheimer’s disease (AD) pathology. The anterior thalamus shows tau deposition early on in AD, while other nuclei, such as the mediodorsal (MD) thalamus are spared by tau until much later in the disease process (Braak and Braak, 1991). Furthermore, anterior and MD thalamus have dissociable roles in memory performance – the anterior has a greater role in recollective memory, while the MD plays a role in familiarity. Additionally, the anterior thalamus has direct anatomical links to brain regions implicated in poor short‐term memory performance in AD, while MD thalamus connectivity is primarily to regions spared of AD pathology until late. We sought to identify differences in functional connectivity between the anterior and MD thalamus in amyloid negative and positive individuals.MethodWe examined resting‐state functional MRI data from the A4 study (n = 569), including 254 healthy controls and 315 individuals with preclinical AD based on amyloid SUVR>1.14 (Table 1). We assessed functional connectivity of anterior and MD thalamus to the whole brain using 2mm radius spherical seeds at the center of mass of Morel atlas nuclei. All results were covaried for age, sex, handedness, and years of education.ResultAnterior thalamic activity was positively correlated with parahippocampal gyrus, fusiform, and insula, and negatively with the striatum and thalamus. MD thalamic activity was positively correlated with the amygdala, ventral striatum, and anterior cingulate, and negatively correlated to the superior temporal gyrus and regions of the parieto‐occipital lobe. In preclinical AD, compared with HCs, the positive correlations in either thalamic nuclei were lost.ConclusionThe thalamic functional connectivity observed agrees with preexisting literature dissociating structures related to the anterior and MD thalamus. Our results provide a basis for further exploration of thalamic nuclei to AD‐involved functional networks, as well as future analysis of the observed connectivity measures to cognition.

Functional connectivity changes of the Locus Coeruleus in Alzheimer’s Disease

AbstractBackgroundGrowing evidence indicates neurone loss in the Locus Coeruleus(LC) in patients with Alzheimer’s Disease(AD). The widespread projection and rich connectivity of the LC with multiple brain regions and its interaction with different neural networks suggests the importance of investigating the functional connectivity of the LC, an area of research which has been less studied. Aims: The primary aim of this study was to test for differences in functional connectivity of the LC between AD subjects and matched controls using neuromelanin‐sensitive MRI(NM‐MRI). The secondary aim of this study was to test for the effects of AD on the resting state networks.MethodPre‐processing of the fMRI and structural MRI data from 23 AD subjects and 23 controls was completed using the FMRIB Software Library(FSL). The images were skull‐stripped, registered, and normalised to the MNI152_t1_2mm_brain template. LC masks were created from the NM‐MRI scans also using FSL. The subsequent data was processed using the CONN toolbox. Seed‐to‐voxel and ROI‐ROI analysis were used to produce connectivity maps and comparisons were conducted between AD and controls, left and right LC, mild and moderate AD, and resting state networks.ResultAD subjects had connections from the LC to only 43 brain regions, compared to 80 brain regions in the controls. In comparison to controls, AD subjects had reduced LC connectivity in the subcallosal cortex(p‐FDR = 0.016417), increased LC connectivity in the right supramarginal and postcentral gyri(p‐FDR = 0.000002), and reduced connectivity in the default mode network(p‐FDR = 0.000286) and sensorimotor network(p‐FDR = 0.027524). The left LC in the AD subjects had significant connections to only 56 brain regions compared to 81 brain regions in the right LC. In particular, the left LC had decreased number of significant connections to the amygdala and vermis, compared to the right LC. The number of significant LC connections decreased with progression from controls to mild AD to moderate AD.ConclusionThis study provides new evidence of reduced LC functional connectivity in AD patients and asymmetrical reduction in the LC skewed towards the left LC. LC connectivity reduction could indicate pathogenesis and progression of AD, aiding prediction of disease progression and development of novel intervention targets.

Uncovering individual variations in bystander intervention of injustice through intrinsic brain connectivity patterns

When confronted with injustice, individuals often intervene as third parties to restore justice by either punishing the perpetrator or helping the victim, even at their own expense. However, little is known about how individual differences in third-party intervention propensity are related to inter-individual variability in intrinsic brain connectivity patterns and how these associations vary between help and punishment intervention. To address these questions, we employed a novel behavioral paradigm in combination with resting-state fMRI and inter-subject representational similarity analysis (IS-RSA). Participants acted as third-party bystanders and needed to decide whether to maintain the status quo or intervene by either helping the disadvantaged recipient (Help condition) or punishing the proposer (Punish condition) at a specific cost. Our analyses focused on three brain networks proposed in the third-party punishment (TPP) model: the salience (e.g., dorsal anterior cingulate cortex, dACC), central executive (e.g., dorsolateral prefrontal cortex, dlPFC), and default mode (e.g., dorsomedial prefrontal cortex, dmPFC; temporoparietal junction, TPJ) networks. IS-RSA showed that individual differences in resting-state functional connectivity (rs-FC) patterns within these networks were associated with the general third-party intervention propensity. Moreover, rs-FC patterns of the right dlPFC and right TPJ were more strongly associated with individual differences in the helping propensity rather than the punishment propensity, whereas the opposite pattern was observed for the dmPFC. Post-hoc predictive modeling confirmed the predictive power of rs-FC in these regions for intervention propensity across individuals. Collectively, these findings shed light on the shared and distinct roles of key regions in TPP brain networks at rest in accounting for individual variations in justice-restoring intervention behaviors.

Deep learning with explainability for characterizing age-related intrinsic differences in dynamic brain functional connectivity.

Although many deep learning models-based medical applications are performance-driven, i.e., accuracy-oriented, their explainability is more critical. This is especially the case with neuroimaging, where we are often interested in identifying biomarkers underlying brain development or disorders. Herein we propose an explainable deep learning approach by elucidating the information transmission mechanism between two layers of a deep network with a joint feature selection strategy that considers several shallow-layer explainable machine learning models and sparse learning of the deep network. At the end, we apply and validate the proposed approach to the analysis of dynamic brain functional connectivity (FC) from fMRI in a brain development study. Our approach can identify the differences within and between functional brain networks over age during development. The results indicate that the brain network transits from undifferentiated structures to more specialized and organized ones, and the information processing ability becomes more efficient as age increases. In addition, we detect two developmental patterns in the brain network: the FCs in regions related to visual and sound processing and mental regulation become weakened, while those between regions corresponding to emotional processing and cognitive activities are enhanced.

Heart Rate Variability during Slow Wave Sleep is Linked to Resting‐state Functional Connectivity in the Central Autonomic Network among Older Adults ‘at‐risk’ of Dementia

AbstractBackgroundReduced heart rate variability (HRV) can be an early sign of autonomic dysfunction in neurodegenerative diseases, and may be related to brain dysfunction in the central autonomic network (CAN). As yet, such autonomic dysfunction has not been examined during sleep – which is an ideal physiological state to study brain‐heart interaction as both the central and peripheral nervous systems behave differently compared to during wakefulness. Therefore, we aimed to examine whether nocturnal HRV, especially slow wave sleep (SWS), is associated with CAN functional connectivity in older adults ‘at‐risk’ of dementia.MethodOlder adults (n = 78; age range = 50‐88 years; 64% female) attending a memory clinic for cognitive concerns underwent resting‐state functional magnetic resonance imaging and an overnight polysomnography. From these, CAN functional connectivity strength and HRV data during sleep were derived, respectively. High‐frequency heart rate variability (HF‐HRV) was extracted to index parasympathetic activity during distinct periods of sleep, including SWS as well as secondary outcomes of non‐rapid eye movement sleep, wake after sleep onset, and rapid eye movement sleep. General linear models were used to examine associations between CAN functional connectivity and HF‐HRV.ResultAnalyses revealed that increased HF‐HRV during SWS was associated with stronger functional connectivity (F = 3.98, p = 0.022) in two core brain regions within the CAN, the right anterior insular and posterior midcingulate cortex, as well as stronger functional connectivity (F = 6.21, p = 0.005) between broader CAN brain regions – the right amygdala with three sub‐nuclei of the thalamus. There were no significant associations between HF‐HRV and CAN functional connectivity during wake after sleep onset or rapid eye movement sleep.ConclusionThese findings show that in older adults ‘at‐risk’ of dementia, parasympathetic regulation during SWS is uniquely linked to differential functional connectivity within both core and broader CAN brain regions. It is possible that dysfunctional brain‐heart interactions manifest primarily during this specific period of sleep known for its role in memory and metabolic clearance. Further studies elucidating the pathophysiology and directionality of this relationship should be conducted to determine if HRV drives neurodegeneration, or if brain degeneration within the CAN promotes aberrant HRV.

Association between gene expression and altered resting-state functional networks in type 2 diabetes

BackgroundType 2 diabetes (T2DM) is a polygenic metabolic disorder that accelerates brain aging and harms cognitive function. The underlying mechanism of T2DM-related brain functional changes has not been clarified.MethodsResting-fMRI data were obtained from 99 T2DM and 109 healthy controls (HCs). Resting-state functional connectivity networks (RSNs) were separated using the Independent Component Analysis (ICA) method, and functional connectivity (FC) differences between T2DM patients and HCs within the RSNs were detected. A partial least squares (PLS) regression was used to test the relation between gene expression from Allen Human Brain Atlas (AHBA) and intergroup FC differences within RSNs. Then the FC differences-related gene sets were enriched to determine the biological processes and pathways related to T2DM brain FC changes.ResultThe T2DM patients showed significantly increased FC in the left middle occipital gyrus (MOG) of the precuneus network (PCUN) and the right MOG / right precuneus of the dorsal attention network (DAN). FC differences within the PCUN were linked with the expression of genes enriched in the potassium channel and TrkB-Rac1 signaling pathways and biological processes related to synaptic function.ConclusionThis study linked FC and molecular alterations related to T2DM and suggested that the T2DM-related brain FC changes may have a genetic basis. This study hoped to provide a unique perspective to understand the biological substrates of T2DM-related brain changes.

Electroencephalogram measured functional connectivity for delirium detection: a systematic review.

Delirium is an acute alteration of consciousness marked by confusion, inattention, and changes in cognition. Some speculate that delirium may be a disorder of functional connectivity, but the requirement to lay still may limit measurement with existing functional imaging modalities in this population. Electroencephalography (EEG) may allow for a more feasible approach to the study of potential connectivity disturbances in delirium. We conducted a systematic review to investigate whether there are EEG-measurable differences in brain functional connectivity in the resting state associated with delirium. Medline, PubMed, PsychInfo, Embase and CINAHL were searched for relevant articles containing original data studying EEG functional connectivity measures in delirium. The search yielded 1,516 records. Following strict inclusion criteria, four studies were included in the review. The studies used a variety of EEG measures including phase lag index, coherence, entropy, shortest path length, minimum spanning tree, and network clustering coefficients to study functional connectivity between scalp electrodes. Across connectivity measures, delirium was associated with decreased brain functional connectivity. All four studies found decreased alpha band connectivity for patients with delirium. None of the studies directly compared the different motor subtypes of delirium. This systematic review provides converging evidence for disturbances in oscillatory-based functional connectivity in delirium.

A table tennis serve versus rally hit elicits differential hemispheric electrocortical power fluctuations.

Human visuomotor control requires coordinated interhemispheric interactions to exploit the brain's functional lateralization. In right-handed individuals, the left hemisphere (right arm) is better for dynamic control and the right hemisphere (left arm) is better for impedance control. Table tennis is a game that requires precise movements of the paddle, whole body coordination, and cognitive engagement, providing an ecologically valid way to study visuomotor integration. The sport has many different types of strokes (e.g., serve, return, and rally shots), which should provide unique cortical dynamics given differences in the sensorimotor demands. The goal of this study was to determine the hemispheric specialization of table tennis serving - a sequential, self-paced, bimanual maneuver. We used time-frequency analysis, event-related potentials, and functional connectivity measures of source-localized electrocortical clusters and compared serves with other types of shots, which varied in the types of movement required, attentional focus, and other task demands. We found greater alpha (8-12 Hz) and beta (13-30 Hz) power in the right sensorimotor cortex than in the left sensorimotor cortex, and we found a greater magnitude of spectral power fluctuations in the right sensorimotor cortex for serve hits than return or rally hits, in all right-handed participants. Surprisingly, we did not find a difference in interhemispheric functional connectivity between a table tennis serve and return or rally hits, even though a serve could arguably be a more complex maneuver. Studying real-world brain dynamics of table tennis provides insight into bilateral sensorimotor integration.NEW & NOTEWORTHY We found different spectral power fluctuations in the left and right sensorimotor cortices during table tennis serves, returns, and rallies. Our findings contribute to the basic science understanding of hemispheric specialization in a real-world context.

Functional connectivity-enhanced feature-grouped attention network for cross-subject EEG emotion recognition

Electroencephalogram (EEG)-based automatic emotion recognition technologies are gaining significant attention and have become crucial in the field of brain–computer interfaces (BCIs). In particular, deep learning methods have been widely used in emotion recognition in recent years. However, most existing methods generally tend to focus on EEG spatiotemporal information, which ignores the potential relationships between brain activity signals and the differences in functional connectivity under different emotions. Here, we raise a functional connectivity-enhanced feature-grouped attention network (FC-FAN) for cross-subject emotion recognition. The FC-FAN model developed is a dual-input model. One input consists of the differential entropy data derived from the original EEG signals, while the other input comprises the functional connectivity data obtained through the calculation of the phase synchronization index. Then the primary EEG features of the two groups’ input data are extracted through two specific residual blocks. Next, the designed time-series feature grouped attention module (TFGAM) and functional connectivity feature grouped attention model (F2GAM) are utilized to mark interested information or suppress uninterested features for the two groups’ features, respectively. Finally, generated information interacts through a fusion operator. The designed framework could not only sufficiently learn the spatiotemporal features of EEG signals but also clearly analyze nonlinear correlations between electrode signals. Comprehensive tests confirm that the FC-FAN has an excellent effect on subject-independent emotion recognition tasks.

Transcriptionally defined amygdala subpopulations play distinct roles in innate social behaviors

Social behaviors are innate and supported by dedicated neural circuits, but the molecular identities of these circuits and how they are established developmentally and shaped by experience remain unclear. Here we show that medial amygdala (MeA) cells originating from two embryonically parcellated developmental lineages have distinct response patterns and functions in social behavior in male mice. MeA cells expressing the transcription factor Foxp2 (MeAFoxp2) are specialized for processing male conspecific cues and are essential for adult inter-male aggression. By contrast, MeA cells derived from the Dbx1 lineage (MeADbx1) respond broadly to social cues, respond strongly during ejaculation and are not essential for male aggression. Furthermore, MeAFoxp2 and MeADbx1 cells show differential anatomical and functional connectivity. Altogether, our results suggest a developmentally hardwired aggression circuit at the MeA level and a lineage-based circuit organization by which a cell’s embryonic transcription factor profile determines its social information representation and behavioral relevance during adulthood.

Empathy-related differences in the anterior cingulate functional connectivity of regular cannabis users when compared to controls.

It has been reported that cannabis consumption affects the anterior cingulate cortex (ACC), a structure with a central role in mediating the empathic response. In this study, we compared psychometric scores of empathy subscales, between a group of regular cannabis users (85, users) and a group of non-consumers (51, controls). We found that users have a greater Emotional Comprehension, a cognitive empathy trait involving the understanding of the "other" emotional state. Resting state functional MRI in a smaller sample (users = 46, controls = 34) allowed to identify greater functional connectivity (FC) of the ACC with the left somatomotor cortex (SMC), in users when compared to controls. These differences were also evident within the empathy core network, where users showed greater within network FC. The greater FC showed by the users is associated with emotional representational areas and empathy-related regions. In addition, the differences in psychometric scores suggest that users have more empathic comprehension. These findings suggest a potential association between cannabis use, a greater comprehension of the other's affective state and the functional brain organization of the users. However, further research is needed to explore such association, since many other factors may be at play.

Hippocampal Resting State Functional Connectivity Associated with Physical Activity in Periadolescent Children.

Periadolescence is a neurodevelopmental period characterized by structural and functional brain changes that are associated with cognitive maturation. The development of the functional connectivity of the hippocampus contributes to cognitive maturation, especially memory processes. Notably, hippocampal development is influenced by lifestyle factors, including physical activity. Physical activity has been associated with individual variability in hippocampal functional connectivity. However, this relationship has not been characterized in a developmental cohort. In this study, we aimed to fill this gap by investigating the relationship between physical activity and the functional connectivity of the hippocampus in a cohort of periadolescents aged 8-13 years (N = 117). The participants completed a physical activity questionnaire, reporting the number of days per week they performed 60 min of physical activity; then, they completed a resting-state functional MRI scan. We observed that greater physical activity was significantly associated with differences in hippocampal functional connectivity in frontal and temporal regions. Greater physical activity was associated with decreased connectivity between the hippocampus and the right superior frontal gyrus and increased connectivity between the hippocampus and the left superior temporal sulcus. Capturing changes in hippocampal functional connectivity during key developmental periods may elucidate how lifestyle factors including physical activity influence brain network connectivity trajectories, cognitive development, and future disease risk.

The effect of SARS-CoV-2 virus on resting-state functional connectivity during adolescence: Investigating brain correlates of psychotic-like experiences and SARS-CoV-2 related inflammation response

We first aimed to investigate resting-state functional connectivity (rs-FC) differences between adolescents exposed to SARS-CoV-2 and healthy controls. Secondly, the moderator effect of PLEs on group differences in rs-FC was examined. Thirdly, brain correlates of inflammation response during acute SARS-CoV-2 infection were investigated. Eighty-two participants aged between 14 and 24 years (SARS-CoV-2 (n = 35), controls (n = 47)) were examined using rs-fMRI. Seed-based rs-FC analysis was performed. The positive subscale of Community Assessment of Psychotic Experiences-42 (CAPE-Pos) was used to measure PLEs. The SARS-CoV-2 group had a lesser rs-FC within sensorimotor network (SMN), central executive network (CEN) and language network (LN), but an increased rs-FC within visual network (VN) compared to controls. No significant differences were detected between the groups regarding CAPE-Pos-score. However, including CAPE-Pos as a covariate, we found increased rs-FC within CEN and SN in SARS-CoV-2 compared to controls. Among the SARS-CoV-2 group, neutrophil/lymphocyte and thrombocyte*neutrophil/lymphocyte ratio was correlated with decreased/increased FC within DMN and SN, and increased FC within CEN. Our results showed rs-FC alterations within the SMN, CEN, LN, and VN among adolescents exposed to SARS-CoV-2. Moreover, changes in rs-FC associated with PLEs existed in these adolescents despite the absence of clinical changes. Furthermore, inflammation response was correlated with alterations in FC within the triple network system.

Disrupted network interactions serve as a neural marker of dyslexia

Dyslexia, a frequent learning disorder, is characterized by severe impairments in reading and writing and hypoactivation in reading regions in the left hemisphere. Despite decades of research, it remains unclear to date if observed behavioural deficits are caused by aberrant network interactions during reading and whether differences in functional activation and connectivity are directly related to reading performance. Here we provide a comprehensive characterization of reading-related brain connectivity in adults with and without dyslexia. We find disrupted functional coupling between hypoactive reading regions, especially between the left temporo-parietal and occipito-temporal cortices, and an extensive functional disruption of the right cerebellum in adults with dyslexia. Network analyses suggest that individuals with dyslexia process written stimuli via a dorsal decoding route and show stronger reading-related interaction with the right cerebellum. Moreover, increased connectivity within networks is linked to worse reading performance in dyslexia. Collectively, our results provide strong evidence for aberrant task-related connectivity as a neural marker for dyslexia that directly impacts behavioural performance. The observed differences in activation and connectivity suggest that one effective way to alleviate reading problems in dyslexia is through modulating interactions within the reading network with neurostimulation methods.

Does right hemisphere compensate for the left in school-age children with large left middle fossa arachnoid cysts?

BackgroundTo assess the cognitive function changes and brain network neuroplasticity in school-age children having large (diameter > 5 cm) left middle fossa arachnoid cyst (MFACs).MethodsEleven patients and 22 normal controls (NC) between 6 and 14 years of age were included. The CNS Vital Signs (CNS VS) were administered for cognitive assessment. The differences of cognitive data and functional connectivity (FC) in resting-state functional magnetic resonance imaging (rs-fMRI) were compared between the patient group and the NC group. The correlations between the altered FC and cognitive data in the patient group were assessed.ResultsPatient group had significantly poorer attention (including Complex Attention, Sustained Attention, Simple Attention, Cognitive Flexibility, and Executive Function) and memory function (Visual Memory and Working Memory) than the NC group (uncorrected p-value, p-unc < 0.05). Whole-brain local correlation (LCOR) analysis showed an extensively lower LCOR in the patient group (voxel threshold p-unc < 0.001, cluster-size threshold of false discovery rate adjusted p (p-FDR) < 0.001). Functional connectivity (FC) analysis showed that bilateral frontal and temporal lobes connectivity in the patient group was significantly lower than the NC group (p-FDR < 0.05). Seed-based FC analysis indicated that there was altered FC between the right temporal lobe and the left temporal-parietal/temporal-occipital area (p-FDR < 0.05). In the patient group, most of the altered FC had a negative correlation to the cognitive score, while the FC in the right temporal lobe-left temporal-occipital area positively correlated to Verbal/Visual Memory (r = 0.41–0.60, p-FDR < 0.05). In correlation analysis between clinical data and cognitive score, the only significant result was a low correlation between cyst size and Reaction Time (-0.30–-0.36, P-FDR < 0.05).ConclusionsSchool-aged children with large left MFAC showed significantly lower cognitive performance primarily in attention and memory domains. Distinct from neuroplasticity in a unilateral brain lesion, compensation in the healthy hemisphere in MFAC patients was sparse.

Cognitive reappraisal and corresponding neural basis mediate the association between childhood maltreatment and depression

BackgroundChildhood maltreatment is considered as a robust predictor of depression. However, the underlying psychological and neurological mechanisms linking childhood maltreatment and depression remain poorly understood. Sufficient evidence demonstrates emotion dysregulation in individuals who have experienced childhood maltreatment, but it is unknown whether these changes represent vulnerability for depression. Here we speculated that decreased cognitive reappraisal and its corresponding neural basis might explain the relationship between childhood maltreatment and follow-up depression. MethodsFirst, we investigated whether cognitive reappraisal can explain the relationship between childhood maltreatment and depression, with a cross-sectional (n = 657) behavioral sample. Then we recruit 38 maltreated participants and 27 controls to complete the cognitive reappraisal functional magnetic resonance imaging (fMRI) task. The between-group difference in brain activation and functional connectivity (FC) were tested using independent t-tests. Finally, we investigated the relationship between childhood maltreatment, task-based brain activity and depression. ResultsThe behavior results suggested that cognitive reappraisal mediates the association between childhood maltreatment and depression. In addition, the maltreated group exhibited lower activation of orbitofrontal cortex (OFC) and higher FC of between the dorsolateral prefrontal cortex (DLPFC), posterior cingulate cortex (PCC), OFC, and amygdala during cognitive reappraisal, compared with healthy controls. Furthermore, the FC of DLPFC-amygdala mediates the association between childhood maltreatment and depression. ConclusionIn summary, childhood maltreatment is associated with inefficient cognitive reappraisal ability, manifesting as aberrant modulation of cortical areas on amygdala. These cognitive and neural deficits might explain the relationship between childhood maltreatment and risk of depression in later life.

Difference in functional connectivity between end-stage renal disease patients with and without restless legs syndrome: A prospective study.

The purpose of this study was to examine differences in functional connectivity between patients with end-stage renal disease (ESRD) with and without restless legs syndrome (RLS). In addition, the study aimed to identify any potential associations between RLS severity and functional connectivity. We enrolled patients with ESRD who had been undergoing hemodialysis. Patients with and without RLS were separated into two groups. Using functional near-infrared spectroscopy (fNIRS) and a graph theory approach, we determined the functional connectivity of patients with ESRD. The data were collected during a 300-s resting state evaluation performed in the dialysis room prior to dialysis. Eighteen of 48 patients with ESRD were diagnosed with RLS, whereas 30 patients did not exhibit RLS symptoms. Notably, functional connectivity metrics differed significantly between patients with and without RLS. Specifically, patients withESRD and RLS displayed higher values for mean clustering coefficient (0.474 vs. 0.352, p = 0.001), global efficiency (0.520 vs. 0.414, p = 0.001), strength (6.538 vs. 4.783, p = 0.001), and transitivity (0.714 vs. 0.521, p = 0.001), while values for diameter (5.451 vs. 7.338, p = 0.002), eccentricity (4.598 vs. 5.985, p = 0.004), and characteristic path length (2.520 vs. 3.271, p = 0.002) were lower in patientswithESRD and RLS compared to those without RLS. In addition, there were correlations between the RLS severity score and the assortative coefficient (r = 0.479, p = 0.044), the small-worldness index (r = -0.475, p = 0.046), and transitivity (r = 0.500, p = 0.034). We demonstrated differences in functional connectivity between patients withESRD with and without RLS, which may shed light on the pathophysiology of RLS. Notably, a number of functional connectivity metrics demonstrated strong associations with RLS severity. Our study also confirmed the applicability of fNIRS as a tool for investigating functional connectivity in patients with RLS.

The changes of intrinsic connectivity contrast in young smokers.

Previous studies demonstrated that reward circuit plays an important role in smoking. The differences of functional and structural connectivity were found among several brain regions such as thalamus and frontal lobe. However, few studies focused on functional connectivity (FC) in whole-brain voxel level of young smokers. In this study, intrinsic connectivity contrast (ICC) was used to perform voxel-based whole-brain analyses in 55 young smokers and 55 matched non-smokers to identify brain regions with significant group differences. ICC results showed that the connectivity of young smokers in medial frontal cortex (MedFC), supramarginal gyrus anterior division left (L_aSMG), central opercular cortex left (L_CO) and middle frontal gyrus left (L_MidFG) showed a significantly lower trend compared with the non-smokers. The seed-based FC analysis about MedFC indicated that young smokers showed reduced connectivity between the MedFC and left hippocampus, left amygdala compared to non-smokers. Correlation analysis showed that the ICC of MedFC in young smokers was significantly negatively correlated with Fagerstrom test for nicotine dependence (FTND) and Questionnaire on Smoking Urges (QSU). The FC between the MedFC and left hippocampus, left amygdala was significantly negatively correlated with Pack_years. The mediation analysis indicated that ICC of MedFC completely mediated FTND and QSU of young smokers. The results suggest that nicotine accumulation may affect the communication of the frontal lobe with the whole brain to some extent, leading to changes in smoking cravings. The above research also provides in-depth insights into the mechanism of adolescent smoking addiction and related intervention treatment.

The Dichotomy of Threat and Deprivation as Subtypes of Childhood Maltreatment: Differential Functional Connectivity Patterns of Threat and Reward Circuits in an Adult Trauma Sample

BackgroundChildhood maltreatment is associated with reduced activation of the nucleus accumbens, a central region in the reward network, and overactivity in the amygdala, a key region in threat processing. However, the long-lasting impact of these associations in the context of later-life stress is not well understood. The current study explored the association between childhood threat and deprivation and functional connectivity of threat and reward regions in an adult trauma sample. MethodsTrauma survivors (N = 169; mean age [SD] = 32.2 [10.3] years; female = 55.6%) were recruited from a level I trauma center. Two weeks after injury, participants completed the Childhood Trauma Questionnaire (measuring experiences of threat and deprivation) and underwent resting-state functional magnetic resonance imaging. Seed-to-voxel analyses evaluated the effect of childhood threat and deprivation on amygdala and nucleus accumbens resting-state connectivity. ResultsHigher levels of threat were associated with increased connectivity between the right nucleus accumbens with temporal fusiform gyrus/parahippocampal gyrus and the left amygdala and the precuneus (false discovery rate–corrected p < .05). After controlling for posttraumatic symptoms 2 weeks posttrauma and lifetime trauma exposure, only the nucleus accumbens findings survived. There were no significant relationships between experiences of childhood deprivation and amygdala or nucleus accumbens connectivity. ConclusionsExperiences of threat are associated with increased nucleus accumbens and amygdala connectivity, which may reflect a preparedness to detect salient and visual stimuli. This may also reflect a propensity toward dysregulated reward processing. Overall, these results suggest that childhood threat may be contributing to aberrant neural baseline reward and threat sensitivity later in life in an adult trauma sample.