The brain's default network: anatomy, function, and relevance to disease

Neural dynamics of deception: insights from fMRI studies of brain states

Deception is a complex behavior that requires greater cognitive effort than truth-telling, with brain states dynamically adapting to external stimuli and cognitive demands. Investigating these brain states provides valuable insights into the brain's temporal and spatial dynamics. In this study, we designed an experiment paradigm to efficiently simulate lying and constructed a temporal network of brain states. We applied the Louvain community clustering algorithm to identify characteristic brain states associated with lie-telling, inverse-telling, and truth-telling. Our analysis revealed six representative brain states with unique spatial characteristics. Notably, two distinct states-termed truth-preferred and lie-preferred-exhibited significant differences in fractional occupancy and average dwelling time. The truth-preferred state showed higher occupancy and dwelling time during truth-telling, while the lie-preferred state demonstrated these characteristics during lie-telling. Using the average z-score BOLD signals of these two states, we applied generalized linear models with elastic net regularization, achieving a classification accuracy of 88.46%, with a sensitivity of 92.31% and a specificity of 84.62% in distinguishing deception from truth-telling. These findings revealed representative brain states for lie-telling, inverse-telling, and truth-telling, highlighting two states specifically associated with truthful and deceptive behaviors. The spatial characteristics and dynamic attributes of these brain states indicate their potential as biomarkers of cognitive engagement in deception.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11571-025-10222-4.

Neuroenhancement by repetitive transcranial magnetic stimulation (rTMS) on DLPFC in healthy adults

The term "neuroenhancement" describes the enhancement of cognitive function associated with deficiencies resulting from a specific condition. Nevertheless, there is currently no agreed-upon definition for the term "neuroenhancement", and its meaning can change based on the specific research being discussed. As humans, our continual pursuit of expanding our capabilities, encompassing both cognitive and motor skills, has led us to explore various tools. Among these, repetitive Transcranial Magnetic Stimulation (rTMS) stands out, yet its potential remains underestimated. Historically, rTMS was predominantly employed in studies focused on rehabilitation objectives. A small amount of research has examined its use on healthy subjects with the goal of improving cognitive abilities like risk-seeking, working memory, attention, cognitive control, learning, computing speed, and decision-making. It appears that the insights gained in this domain largely stem from indirect outcomes of rehabilitation research. This review aims to scrutinize these studies, assessing the effectiveness of rTMS in enhancing cognitive skills in healthy subjects. Given that the dorsolateral prefrontal cortex (DLPFC) has become a popular focus for rTMS in treating psychiatric disorders, corresponding anatomically to Brodmann areas 9 and 46, and considering the documented success of rTMS stimulation on the DLPFC for cognitive improvement, our focus in this review article centers on the DLPFC as the focal point and region of interest. Additionally, recognizing the significance of theta burst magnetic stimulation protocols (TBS) in mimicking the natural firing patterns of the brain to modulate excitability in specific cortical areas with precision, we have incorporated Theta Burst Stimulation (TBS) wave patterns. This inclusion, mirroring brain patterns, is intended to enhance the efficacy of the rTMS method. To ascertain if brain magnetic stimulation consistently improves cognition, a thorough meta-analysis of the existing literature has been conducted. The findings indicate that, after excluding outlier studies, rTMS may improve cognition when compared to appropriate control circumstances. However, there is also a considerable degree of variation among the researches. The navigation strategy used to reach the stimulation site and the stimulation location are important factors that contribute to the variation between studies. The results of this study can provide professional athletes, firefighters, bodyguards, and therapists-among others in high-risk professions-with insightful information that can help them perform better on the job.

The body intervenes: How active inference explains depression's clinical presentation

The low mood that characterises depression is accompanied by changes in bodily processes, manifested in symptoms such as insomnia, reduced appetite and fatigue. The active inference framework provides an explanation as to how mood-related symptoms are linked. It suggests that affective experiences arise from predictions about interoceptive states and their corresponding prediction errors, with the relative influence of each modified by precision weighting. Moods reflect long-term predictions about the state of the body, incorporating parameters related to sleep, appetite and energy levels. Depression emerges from the interplay between reduced confidence in long-term prospects and heightened expectation of shorter-term negative affect, which sees a re-weighting of the precision of interoceptive prediction errors. The ensuing bodily changes contribute to the emergence of depressed mood; and underpin disturbances in shorter-term interoceptive predictions and the experience of emotions such as anxiety and irritability. This framework details how interoceptive processes shape the phenomenological and symptomatic experience of depression, helping us to understand the disorder's multifaceted and often idiosyncratic clinical presentation, and with implications for the way we understand and treat depression and its co-morbidities.

Language processing in emergencies recruits both language and default mode networks

Effective language processing in emergencies is crucial for professionals, including firefighters, soldiers, and doctors. Substantial research has been undertaken on language processing in silence, with several studies indicating the impact of noise on language processing in non-emergencies. However, it remains unclear about the neural mechanisms involved in language processing during emergencies, especially the role of the language network (LN) and the default mode network (DMN) in such contexts. In this study, we adopted functional near-infrared spectroscopy (fNIRS) to investigate brain activities of 60 participants who were performing language processing tasks in simulated high-emergency and low-emergency scenarios. Compared to the resting state, the reading task demonstrated reduced activation in bilateral superior and middle frontal gyri (SFG/MFG), components of the DMN, alongside enhanced activation in Broca's area, left temporal lobe and left inferior parietal lobule (IPL) - key LN regions. Furthermore, the activity of the left MFG was positively correlated with the level of stress experienced by participants during the task. Additionally, a positive correlation was identified between language processing performance and activation of the left MFG, exclusively in the participants exposed to high-emergency scenarios. These results support the view that language processing during emergency relies on both the LN and DMN. The current study deepens our understanding of the neural mechanisms that underlie language processing in complex, real-life emergency scenarios.

Vascular depression: A comprehensive exploration of the definition, mechanisms, and clinical challenges

Vascular depression (VaDep), which was proposed over two decades ago, is a distinct subtype of depression primarily observed in patients with stroke and cerebral small-vessel disease and is characterized by white matter hyperintensities; however, the lack of standardized diagnostic criteria and consensus limits its clinical application. This review explores the pathological conditions and vascular risk factors that may precipitate VaDep, particularly in relation to stroke and cerebral small-vessel disease. VaDep is distinguished by unique pathophysiological mechanisms and treatment responses. We categorize these mechanisms into three groups: 1) macroscopic mechanisms, including vascular aging, cerebral hypoperfusion, blood-brain barrier disruption, and neural circuit dysfunction; 2) microscopic mechanisms, involving the inflammatory response, hypothalamic-pituitary-adrenal axis dysregulation, impaired monoamine synthesis, and mitochondrial dysfunction; and 3) undetermined mechanisms, such as microbiota-gut-brain axis dysbiosis. These insights support VaDep as a distinct depression subtype, differentiating it from late-life depression and major depressive disorder. Treatment is challenging, as patients with VaDep often exhibit resistance to conventional antidepressants. Addressing vascular risk factors and protecting vascular integrity are essential for effective management. Future research should validate these mechanisms and develop novel diagnostic and therapeutic approaches to improve VaDep outcomes.

Cochlear neural contributions to triple network changes in tinnitus, hyperacusis & misophonia? A perspective review

What do tinnitus, the perception of sounds without an internal or external source of noise, hyperacusis, the pathological hypersensitivity to noise, or misophonia, an intolerance to certain everyday noises, have in common, and what differentiates them? A large number of excellent studies focused in the last few decades on identifying the neural correlates of tinnitus, hyperacusis, or misophonia on the basis of central triple-network changes. In this perspective review we explicitly examine, possible differential and causal involvement of peripheral components as a presumptive trigger that may drive observed triple-network changes. Based on our results, we venture to hypothesize that: (i) tinnitus, hyperacusis, and misophonia can occur despite clinically normal hearing thresholds, and are likely causally independent of sex and age, (ii) tinnitus and hyperacusis, but possibly also misophonia are related to altered auditory processing that through desynchronized (tinnitus) or hyperactive (hyperacusis, misophonia) bottom-up ascending processing potentially explains the activity changes in, e.g., default or salient brain networks, as suggested in various studies of these different diseases. (iii) In misophonia a stress-induced top-down influence, as deep as the auditory nerve fibers, may be discussed as a contributor to generating misophonia-trigger sounds, a hypothesis that can be tested in future studies. We hope that the selective consideration of a possible interaction between peripheral and central components will help to minimize the greatest handicap of these pathologies to date towards successful therapy: the lack of clarification of the underlying causative mechanism of the diseases.

Transdiagnostic network alterations and associated neurotransmitter signatures across major psychiatric disorders in adolescents: Evidence from edge-centric analysis of time-varying functional brain networks

BACKGROUND

Adolescence is a pivotal phase marked by heightened vulnerability to the onset of psychiatric disorders. However, there are few transdiagnostic studies of dynamic brain networks across major psychiatric disorders during this phase.

METHODS

We collected resting-state functional MRI data from 189 adolescent patients (61 with bipolar disorder, 73 with major depressive disorder, and 55 with schizophrenia) and 181 healthy adolescents. Functional networks were constructed using a state-of-art edge-centric dynamic functional connectivity (DFC) approach.

RESULTS

Four DFC states were identified for the healthy adolescents that were related to different behavioral and cognitive terms. Disorder-related alterations were observed in two states involving motor and somatosensory processing and one state involving various cognitive functions. Regardless of the state, the three patient groups exhibited lower FC that were mainly involved in edges between different functional subsystems and were predominantly linked to regions in the somatomotor network. The patients with major depressive disorder additionally showed increased FC that were primarily linked to default mode regions. Graph-based network analysis revealed different patterns of disrupted small-world organization and altered nodal degree in the disorders in a state-dependent manner. The nodal degree alterations were correlated with the concentration of various neurotransmitters. Intriguingly, the noradrenaline concentration was engaged in the nodal degree alterations in each patient group. Finally, decreased FC involving regions in the somatomotor network showed significant correlations with clinical variables in the major depressive disorder patients.

CONCLUSION

These findings may help understand the developmental pathways associated with the heightened vulnerability to major psychiatric disorders during adolescence.

Neural basis underlying the effects of trait and state anxiety on premature ejaculation revealed by resting-state interhemispheric functional connectivity

INTRODUCTION

Anxiety is considered to play a key role in the development and maintenance of premature ejaculation (PE). In addition, PE patients often co-occur with anxiety, however, the central mechanisms underlying this comorbidity have remained elusive. This study aimed to explore whether trait and state anxiety-related PE shared common or distinct mechanisms in the brain.

METHODS

A total of 90 PE patients and 45 healthy controls (HCs) were enrolled. Patients were divided into subgroups including 45 patients with low trait anxiety (LTA) and 45 patients with high trait anxiety (HTA) by state and trait anxiety inventory-trait version (STAI-T). In addition, patients were divided into another two groups including 42 patients with low state anxiety (LSA) and 48 patients with high state anxiety (HSA) by STAI-state version (STAI-S). Magnetic resonance imaging (MRI) data were acquired, preprocessed and the measure of voxel-mirrored homotopic connectivity (VMHC) was calculated and compared between all groups. Moreover, we evaluated whether VMHC of brain regions showed distinct mechanisms between trait and state anxiety-related PE were associated with the severity of PE and anxiety.

RESULTS

Compared with HCs, patients with LTA exhibited increased VMHC in the attention network (AN), default mode network (DMN) and subcortical network (SCN), decreased VMHC in DMN while patients with HTA showed increased VMHC in SCN, decreased VMHC in DMN and AN. Compared with patients with LTA, patients with HTA demonstrated decreased VMHC in DMN and AN. Compared with HCs, patients with LSA had increased VMHC in DMN, decreased VMHC in AN and DMN while patients with HSA exhibited increased VMHC in AN, DMN and SCN, decreased VMHC in DMN, AN and sensory-motor network (SMN). Compared with patients with LSA, patients with HSA demonstrated increased VMHC in DMN. Moreover, premature ejaculation diagnostic tool (PEDT) scores were negatively associated with VMHC of DMN and AN while STAI-T scores were negatively related to VMHC of DMN in patients with HTA. PEDT, STAI-S and STAI-T scores were all negatively associated with VMHC of DMN in patients with HSA.

CONCLUSION

Our findings demonstrated that decreased interhemispheric functional connectivity (FC) in DMN and AN might be associated with high trait anxiety-related PE while increased interhemispheric FC in DMN might be relate to high state anxiety-related PE. Therefore, trait and state anxiety-related PE might be driven by distinct mechanisms in the brain.

Where creativity meets aesthetics: The Mirror Model of Art revisited with fMRI

How meaning is conveyed from creator to observer is debated in the psychology of art. The Mirror Model of Art represents a theoretical framework for bridging the psychological processes that underpin creative production and aesthetic appreciation of art. Specifically, it postulates that creating art and having an aesthetic experience are "mirrored" processes such that the early stage of aesthetic appreciation corresponds to the late stage of creative production, and conversely, that the late stage of aesthetic appreciation corresponds to the early stage of creative production. We conducted a meta-analysis of fMRI studies in the visual domain to test this hypothesis. Our results reveal that creative production engages the prefrontal cortex, which we attribute to its role in idea generation, whereas aesthetic appreciation engages the visual cortex, anterior insula, parahippocampal gyrus, the fusiform gyrus, and the frontal lobes, regions involved primarily in sensory, perceptual, reward and mnemonic processing. Their direct comparison revealed that creative production was associated with greater activation in the prefrontal cortex, whereas aesthetic appreciation was associated with greater activation in the visual cortex. This meta-analysis largely supports predictions derived from the Mirror Model of Art, by providing a snapshot of neural activity in the relatively early stages in art creators' and observers' minds. Future studies that capture brain function across longer spans of time are needed to understand the expression of creativity and aesthetic appreciation in different stages of information processing in relation to the Mirror Model of Art.

Functional Brain Networks Underlying Autobiographical Event Simulation: An Update

fMRI studies typically explore changes in the BOLD signal underlying discrete cognitive processes that occur over milliseconds to a few seconds. However, autobiographical cognition is a protracted process and requires fMRI tasks with longer trials to capture the temporal dynamics of the underlying brain networks. In the current study, we provided an updated analysis of the fMRI data obtained from a published autobiographical event simulation study, with a slow event-related design (34-sec trials), that involved participants recalling past, imagining past, and imagining future autobiographical events, as well as completing a semantic association control task. Our updated analysis using Constrained Principal Component Analysis for fMRI retrieved two networks reported in the original study: (1) the Default Mode Network, which activated during the autobiographical event simulation conditions but deactivated during the control condition, and (2) the Multiple Demand Network, which activated early in all conditions during the construction of the required representations (i.e., autobiographical events or semantic associates). Two novel networks also emerged: (1) the Response Network, which activated during the scale-rating phase, and (2) the Maintaining Internal Attention Network, which, while active in all conditions during the elaboration of details associated with the simulated events, was more strongly engaged during the imagination and semantic association control conditions. Our findings suggest that the Default Mode Network does not support autobiographical simulation alone, but it co-activates with the Multiple Demand Network and Maintaining Internal Attention Network, with the timing of activations depending on evolving task demands during the simulation process.

Chronic pain and its association with cognitive decline and brain function abnormalities in older adults: Insights from EEG and neuropsychological assessment

Studies examining the interplay between chronic pain, cognitive function, and functional brain abnormalities in older adults are scarce. To address this gap, we administered a series of neuropsychological tests and recorded electroencephalography (EEG) data during resting-state conditions in 26 older adults with chronic pain (CPOA), 30 pain-free older adults (OA), and 31 younger adults (YA). CPOA demonstrated poorer performance compared to OA on the Stroop test, the Wisconsin Card Sorting Test (WCST) and Digit Span. Both groups of older adults exhibited higher beta activity compared to younger adults, with CPOA displaying particularly elevated beta-2 activity localized in the posterior cingulate cortex compared to OA. Correlational analyses indicated that in CPOA participants, heightened beta activity was linked to decreased performance on the WCST. Conversely, in OA, we observed a positive correlation between beta activity and performance on the WCST. Overall, our findings suggest that the cumulative impact of pain in aging would diminish the effectiveness of the functional compensatory mechanisms that occur during healthy aging, exacerbating cognitive decline.

Brain Activation During Suicide-Specific Cognition in Trauma-Exposed Veterans

INTRODUCTION

The suicide Implicit Association Test (S-IAT) captures the strength of the implicit identification between self and death and is one of the few suicide-specific behavioral tasks that uniquely predicts future suicide risk. Thus, identifying brain regions associated with the S-IAT provides insights into the neural mechanisms underlying suicidality.

METHODS

This study measured brain activation during the S-IAT with concurrent fMRI in a post-9/11 trauma-exposed veteran sample. In total, 37 post-9/11 veterans at low risk for suicide participated in this study as part of an ongoing longitudinal study.

RESULTS

Behaviorally, participants were slower to categorize words during incongruent (death-me) contexts relative to congruent (life-me) contexts (p < 0.001). Whole-brain voxelwise fMRI contrasts revealed a brain network that was significantly more active during incongruent trials than congruent trials that included the bilateral occipital, posterior parietal, and cerebellum (corrected p < 0.05). This increased brain activation corresponded with task performance, suggesting that more brain resources are needed to complete death-me identifications.

CONCLUSIONS

These results suggest that death-me implicit identifications involve resolving conflict between self and death representations in the brain and mark an important step towards characterizing neural mechanisms contributing to suicidality.

Brain Activation Associated With Response to Psychotherapies for Late-Life Depression: A Task-Based fMRI Study

BACKGROUND

The course of late-life depression is associated with functioning of multiple brain networks. Understanding the brain mechanisms associated with response to psychotherapy can inform treatment development and a personalized treatment approach. This study examined how activation of key regions of the salience network, default mode network and reward systems is associated with response to psychotherapies for late-life depression.

METHODS

Thirty-three older adults with major depressive disorder were randomized to 9 weeks of Engage or Problem-Solving Therapy for late-life depression. Participants completed a Probabilistic Reversal Learning task in the MRI at baseline and Week 6. We focused on focal activation in regions of interest selected a priori: the subgenual cingulate cortex (sgACC; DMN); the dorsal anterior cingulate cortex (dACC; salience network and reward system); and the nucleus accumbens (NAcc; reward system). We applied mixed-effects regression models to examine whether brain activation was associated with psychotherapy response.

RESULTS

We found that at baseline, low activation of the dACC and the sgACC was associated with lower depression severity over 6 weeks of psychotherapy. In addition, we observed significant time*activation interactions, such that after 6 weeks of psychotherapy, lower dACC activation and higher NAcc and sgACC activation were each associated with lower depression severity. Further, we found that baseline slower response to negative feedback and faster response to positive feedback was associated with lower depression severity over 6 weeks of psychotherapy.

CONCLUSIONS

Our findings suggest that activation of reward, salience, and DMN regions may serve as markers of response during psychotherapy for late-life depression. Engagement of these networks may be linked to treatment outcome. Personalized psychotherapies can target individuals' brain profiles to improve outcomes for older adults with major depression.

ARTICLE SUMMARY

This study examined whether activation of regions of the reward, salience and default mode networks is associated with response to psychotherapies for late-life depression. We found that baseline low activation of the dACC and the sgACC was associated with lower depression severity during psychotherapy. We also found that at week 6, lower dACC activation and higher NAcc and sgACC activation were linked with lower depression severity. These regions may represent promising brain mechanisms for future personalized interventions.

Causal role of medial superior frontal cortex on enhancing neural information flow and self-agency judgments in the self-agency network

Self-agency is being aware of oneself as the agent of one's thoughts and actions. Self-agency is necessary for successful interactions with the outside world (reality-monitoring). Prior research has shown that the medial superior prefrontal gyri (mPFC/SFG) may represent one neural correlate underlying self-agency judgments. However, the causal relationship remains unknown. Here, we applied high-frequency 10 Hz repetitive transcranial magnetic stimulation (rTMS) to modulate the excitability of the mPFC/SFG site that we have previously shown to mediate self-agency. For the first time, we delineate causal neural mechanisms, revealing precisely how rTMS modulates SFG excitability and impacts directional neural information flow in the self-agency network by implementing innovative magnetoencephalography (MEG) phase-transfer entropy (PTE) metrics, measured from pre-to-post rTMS. We found that, compared to control rTMS, enhancing SFG excitability by rTMS induced significant increases in information flow between SFG and specific cingulate and paracentral regions in the self-agency network in delta-theta, alpha, and gamma bands, which predicted improved self-agency judgments. This is the first multimodal imaging study in which we implement MEG PTE metrics of 5D imaging of space, frequency and time, to provide cutting-edge analyses of the causal neural mechanisms of how rTMS enhances SFG excitability and improves neural information flow between distinct regions in the self-agency network to potentiate improved self-agency judgments. Our findings provide a novel perspective for investigating causal neural mechanisms underlying self-agency and create a path towards developing novel neuromodulation interventions to improve self-agency that will be particularly useful for patients with psychosis who exhibit severe impairments in self-agency.

Task-related reconfiguration patterns of frontoparietal network during motor imagery

Motor imagery (MI) is closely associated with the frontoparietal network that includes prefrontal and posterior parietal regions. Studying task-related network reconfiguration after brain shifts from the resting state to the MI task is an important way to understand the brain's response process. However, how the brain modulates functional connectivity of the frontoparietal network when it shifts to MI has not been thoroughly studied. In this study, we attempted to characterize the frontoparietal network reconfiguration patterns as the brain transitioned to motor imagery tasks. We performed the analysis using EEG signals from 52 healthy subjects during left- and right-hand MI tasks. The results indicated distinct reconfiguration patterns in the frontoparietal network across four typical brain wave rhythms (theta (4 ∼ 7 Hz), alpha (8 ∼ 13 Hz), beta (14 ∼ 30 Hz), and gamma (31 ∼ 45 Hz)). Meanwhile, there was a significant positive correlation between the frontoparietal network reconfiguration and the event-related desynchronization of alpha and beta rhythms in the sensorimotor cortex. We further found that subjects with better MI-BCI performance exhibited greater reconfiguration of the frontoparietal network in alpha and beta rhythms. These findings implied that MI was accompanied by a shift in information interaction between brain regions, which might contribute to understanding the neural mechanisms of MI.

Shared genetics and causal relationship between sociability and the brain's default mode network

BACKGROUND

The brain's default mode network (DMN) plays a role in social cognition, with altered DMN function being associated with social impairments across various neuropsychiatric disorders. However, the genetic basis linking sociability with DMN function remains underexplored. This study aimed to elucidate the shared genetics and causal relationship between sociability and DMN-related resting-state functional MRI (rs-fMRI) traits.

METHODS

We conducted a comprehensive genomic analysis using large-scale genome-wide association study (GWAS) summary statistics for sociability and 31 activity and 64 connectivity DMN-related rs-fMRI traits (N = 34,691-342,461). We performed global and local genetic correlations analyses and bi-directional Mendelian randomization (MR) to assess shared and causal effects. We prioritized genes influencing both sociability and rs-fMRI traits by combining expression quantitative trait loci MR analyses, the CELLECT framework - integrating single-nucleus RNA sequencing (snRNA-seq) data with GWAS - and network propagation within a protein-protein interaction network.

RESULTS

Significant local genetic correlations were identified between sociability and two rs-fMRI traits, one representing spontaneous activity within the temporal cortex, the other representing connectivity between the cingulate and angular/temporal cortices. MR analyses suggested potential causal effects of sociability on 12 rs-fMRI traits. Seventeen genes were highly prioritized, with LINGO1, ELAVL2, and CTNND1 emerging as top candidates. Among these, DRD2 was also identified, serving as a robust internal validation of our approach.

CONCLUSIONS

By combining genomic and transcriptomic data, our gene prioritization strategy may serve as a blueprint for future studies. Our findings can guide further research into the biological mechanisms underlying sociability and its role in the development, prognosis, and treatment of neuropsychiatric disorders.

Altered hemispheres lateralization of brain functional gradients in Alzheimer's disease

BackgroundThe human brain demonstrates intrinsic hemispheric asymmetry across structural, functional, and biochemical domains. While cortical gradients provide a multiscale framework for understanding brain network organization, their hemispheric divergence in Alzheimer's disease (AD) remains unexplored.ObjectiveTo characterize interhemispheric gradient lateralization patterns across the AD continuum and evaluate their clinical correlates.MethodsResting-state fMRI data of 45 normal controls (NC), 45 patients with mild cognitive impairment (MCI), and 45 patients with AD underwent gradient networks processing. Interhemispheric comparisons of mean gradient values were conducted across these groups. A lateralization index (L value) was defined for 17 networks, and differences among the three groups were analyzed using one-way ANOVA. Additionally, correlations between network L values and cognitive scores were examined.ResultsNC and MCI participants exhibited left lateralization of gradient values in the second gradient. In contrast, AD patients showed a loss of interhemispheric lateralization. Notably, AD patients demonstrated reduced lateralization in default mode network (DMN) and control network. The degree of lateralization in DMN was significantly positively correlated with cognitive function.ConclusionsOur findings indicated that patients with AD demonstrated a diminished lateralization in gradient networks. Quantifying gradient laterality may serve as a multimodal biomarker for early AD detection and therapeutic monitoring.

Parietal cortex is recruited by frontal and cingulate areas to support action monitoring and updating during stopping

Recent evidence indicates that the intraparietal sulcus (IPS) may play a causal role in action stopping, potentially representing a novel neuromodulation target for inhibitory control dysfunctions. Here, we leverage intracranial recordings in human subjects to establish the timing and directionality of information flow between IPS and prefrontal and cingulate regions during action stopping. Prior to successful inhibition, information flows primarily from the inferior frontal gyrus (IFG), a critical inhibitory control node, to IPS. In contrast, during stopping errors the communication between IPS and IFG is lacking, and IPS is engaged by posterior cingulate cortex, an area outside of the classical inhibition network and typically associated with default mode. Anterior cingulate and orbitofrontal cortex also display performance-dependent connectivity with IPS. Our functional connectivity results provide direct electrophysiological evidence that IPS is recruited by frontal and anterior cingulate areas to support action plan monitoring and updating, and by posterior cingulate during control failures.

Differential relationships among homocysteine levels, cognitive deficits, and low-frequency fluctuation in brain activity in bipolar disorder with suicidal ideation

BACKGROUND

Suicidal ideation (SI) is a common symptom of bipolar disorder (BD). Patients with BD and suicidal ideation (BDSI) have been shown to exhibit abnormal spontaneous brain activity and homocysteine (Hcy) levels. Additionally, cognitive deficits are also considered to be a critical symptom in BD. However, the relationship among spontaneous brain activity, Hcy levels, and cognitive deficits in patients with BDSI remains unclear.

METHODS

A total of 74 participants were enrolled, comprising individuals with BDSI (n = 20), BD patients without suicidal ideation (BDNSI) (n = 24), and age-/sex-matched healthy controls (HC) (n = 30). Each participant underwent cognitive performance assessments, and blood samples were collected to measure Hcy levels. We then calculated the amplitude of low-frequency fluctuation (ALFF) from resting-state functional magnetic resonance imaging data. Mediated-effects analysis was conducted to explore the association among these three variables.

RESULTS

Hcy levels were significantly higher in the BDNSI group than in the BDSI group (t = 2.33, P = 0.024). Specifically, a significant positive correlation was observed between Hcy levels and the fractional amplitude of low-frequency fluctuation (fALFF) signals in the left posterior cingulate gyrus in the BDSI group (r = 0.644, P = 0.005). Mediation analyses revealed that the left posterior cingulate gyrus significantly mediated the negative relationship between Hcy levels and both visual learning /verbal learning performance (95% confidence intervals for the indirect effects ranging from [Formula: see text]0.592 to [Formula: see text]0.069 and [Formula: see text]0.465 to [Formula: see text]0.042, respectively) in the BDSI group.

CONCLUSIONS

Our data suggest that patients with BDSI and BDNSI may exhibit distinct Hcy-neurocognitive-brain function profiles, which could be further verified by investigating the underlying pathophysiological mechanism of BDSI.

The striatal compartments, striosome and matrix, are embedded in largely distinct resting-state functional networks

The striatum is divided into two interdigitated tissue compartments, the striosome and matrix. These compartments exhibit distinct anatomical, neurochemical, and pharmacological characteristics and have separable roles in motor and mood functions. Little is known about the functions of these compartments in humans. While compartment-specific roles in neuropsychiatric diseases have been hypothesized, they have yet to be directly tested. Investigating compartment-specific functions is crucial for understanding the symptoms produced by striatal injury, and to elucidating the roles of each compartment in healthy human skills and behaviors. We mapped the functional networks of striosome-like and matrix-like voxels in humans in-vivo. We utilized a diverse cohort of 674 healthy adults, derived from the Human Connectome Project, including all subjects with complete diffusion and functional MRI data and excluding subjects with substance use disorders. We identified striatal voxels with striosome-like and matrix-like structural connectivity using probabilistic diffusion tractography. We then investigated resting-state functional connectivity (rsFC) using these compartment-like voxels as seeds. We found widespread differences in rsFC between striosome-like and matrix-like seeds (p < 0.05, family wise error corrected for multiple comparisons), suggesting that striosome and matrix occupy distinct functional networks. Slightly shifting seed voxel locations (<4 mm) eliminated these rsFC differences, underscoring the anatomic precision of these networks. Striosome-seeded networks exhibited ipsilateral dominance; matrix-seeded networks had contralateral dominance. Next, we assessed compartment-specific engagement with the triple-network model (default mode, salience, and frontoparietal networks). Striosome-like voxels dominated rsFC with the default mode network bilaterally. The anterior insula (a primary node in the salience network) had higher rsFC with striosome-like voxels. The inferior and middle frontal cortices (primary nodes, frontoparietal network) had stronger rsFC with matrix-like voxels on the left, and striosome-like voxels on the right. Since striosome-like and matrix-like voxels occupy highly segregated rsFC networks, striosome-selective injury may produce different motor, cognitive, and behavioral symptoms than matrix-selective injury. Moreover, compartment-specific rsFC abnormalities may be identifiable before disease-related structural injuries are evident. Localizing rsFC differences provides an anatomic substrate for understanding how the tissue-level organization of the striatum underpins complex brain networks, and how compartment-specific injury may contribute to the symptoms of specific neuropsychiatric disorders.

Characteristics of positive and negative networks in working memory task of basketball athletes

Working memory (WM) plays a vital role in athletic performance in open-skill sports like basketball. However, sport-induced WM adaptation is complex, and the underlying neural mechanisms remain poorly characterized. Using an N-back task with fMRI, this study investigated the brain function of 55 basketball athletes and 55 gender- and age-matched healthy controls during the WM tasks. The results revealed that basketball athletes showed increased activation in the task-positive network (TPN), reduced inhibitory activation in the default mode network (DMN), and cerebellar-mediated new dynamic between the two networks. These neural adaptations aligned with accelerated response speed at the cost of reduced 2-back accuracy, reflecting a speed-accuracy trade-off optimized for sport-specific demands. Future research should explore interventions targeting DMN regulation alongside TPN engagement to optimize cognitive performance in athletes. By bridging sports neuroscience and cognitive training paradigms, this study offers new insights into how sports training sculpts the brain's functional architecture.

Neural substrates of attack event prediction in video games: the role of ventral posterior cingulate cortex and theory of mind network

Action anticipation, the ability to observe actions and predict the intent of others, plays a crucial role in social interaction and fields such as electronic sports. However, the neural mechanisms underlying the inference of purpose from action observation remain unclear. In this study, we conducted an fMRI experiment using video game combat scenarios to investigate the neural correlates of action anticipation and its relationship with task performance. The results showed that the higher level of ability to infer the purpose from action observation during experiment associates with higher level of proficiency in real world electric gaming competition. The action anticipation task activates visual streams, fronto-parietal network, and the ventral posterior cingulate cortex (vPCC), a key hub in the theory of mind network. The strength of vPCC activation during action anticipation, but not movement direction judgment, was positively correlated with gaming proficiency. Finite impulse response analysis revealed distinct dynamic response profiles in the vPCC compared to other theory of mind regions. These findings suggest that theory of mind ability may be an important factor influencing individual competitive performance, with the vPCC serving as a core neural substrate for inferring purpose from action observation.

How do brain regions specialised for concrete and abstract concepts align with functional brain networks? A neuroimaging meta-analysis

Identifying the brain regions that process concrete and abstract concepts is key to understanding the neural architecture of thought, memory and language. We review current theories of concreteness effects and test their neural predictions in a meta-analysis of 72 neuroimaging studies (1400 participants). Our analysis includes more than twice as many studies as previous meta-analyses, allowing for a more sensitive mapping of these effects across the brain. We also conducted a quantitative assessment of the degree to which concreteness effects aligned with a range of large-scale functional brain networks. Our results suggest that concrete and abstract concepts vary both in the information-processing modalities they engage and in the demands they place on cognitive control processes. Abstract concepts preferentially activated networks for social cognition (particularly for sentences), language and semantic control (particularly when presented as single words). Concrete concepts preferentially activated action processing regions when presented in sentences, though we found no evidence that they activated visual networks. Specialisation for both concept types was present in different parts of the default mode network (DMN), with effects dissociating along a social-spatial axis. Concrete concepts generated greater activation in a medial temporal DMN component, implicated in constructing mental models of spatial contexts and scenes. In contrast, abstract concepts showed greater activation in frontotemporal DMN regions involved in social and language processing. These results align with prior claims that generating models of situations and events is a core DMN function and indicate specialisation within DMN for different aspects of these models.

Joint resting state and structural networks characterize pediatric bipolar patients compared to healthy controls: a multimodal fusion approach

Pediatric bipolar disorder (PBD) is a highly debilitating condition, characterized by alternating episodes of mania and depression, with intervening periods of remission. Limited information is available about the functional and structural abnormalities in PBD, particularly when comparing type I with type II subtypes. Resting-state brain activity and structural grey matter, assessed through MRI, may provide insight into the neurobiological biomarkers of this disorder. In this study, Resting state Regional Homogeneity (ReHo) and grey matter concentration (GMC) data of 58 PBD patients, and 21 healthy controls matched for age, gender, education and IQ, were analyzed in a data fusion unsupervised machine learning approach known as transposed Independent Vector Analysis. Two networks significantly differed between BPD and HC. The first network included fronto- medial regions, such as the medial and superior frontal gyrus, the cingulate, and displayed higher ReHo and GMC values in PBD compared to HC. The second network included temporo-posterior regions, as well as the insula, the caudate and the precuneus and displayed lower ReHo and GMC values in PBD compared to HC. Additionally, two networks differ between type-I vs type-II in PBD: an occipito-cerebellar network with increased ReHo and GMC in type-I compared to type-II, and a fronto-parietal network with decreased ReHo and GMC in type-I compared to type-II. Of note, the first network positively correlated with depression scores. These findings shed new light on the functional and structural abnormalities displayed by pediatric bipolar patients.

Functional brain connectivity changes following Masterson Psychotherapy in borderline personality disorder: a pilot study

The Masterson Psychotherapy (MP) is a therapeutic method used to manage symptoms of Borderline Personality Disorder (BPD). This pilot study aimed to investigate the effects of MP on brain connectivity in individuals with BPD using resting-state fMRI. We collected resting-state fMRI data from 10 individuals with BPD before and after 20 MP sessions to examine changes in brain connectivity. Pre-therapy data from these individuals were also compared to data from 10 healthy controls. Results showed reduced hippocampal connectivity in individuals with BPD compared to controls, which significantly improved following MP. Notably, improvements in hippocampal connectivity were correlated with clinical reductions in BPD symptoms. This preliminary study suggests that the therapeutic benefits of MP in BPD may be associated with enhanced hippocampal connectivity.

Gray and white matter alterations in Obsessive-Compulsive Personality Disorder: a data fusion machine learning approach

Introduction

Obsessive-Compulsive Personality Disorder (OCPD) is a complex mental condition marked by excessive perfectionism, orderliness, and rigidity, often starting in adolescence or early adulthood; it affects 1.9% to 7.8% of the population. The disorder differs from Obsessive-Compulsive Disorder (OCD) in an apparent compromise of personality, distorted self-representation, and altered perception of others. Although the two disorders present evident differences, unlike OCD, the neural bases of OCPD are understudied. The few studies conducted so far have identified gray matter alterations in brain regions such as the striatum and prefrontal cortex. However, a comprehensive model of its neurobiology and the eventual contribution of white matter abnormalities are still unclear. One intriguing hypothesis is that regions ascribed to the Default Mode Network are involved in OCPD, similar to what has been shown for OCD and other anxiety disorders.

Methods

To test this hypothesis, the gray and white matter images of 30 individuals diagnosed with OCPD (73% female, mean age=29.300), and 34 non-OCPD controls (82% female, mean age = 25.599) were analyzed for the first time with a data fusion unsupervised machine learning method known as Parallel Independent Component Analysis (pICA) to detect the joint contribution of these modalities to the OCPD diagnosis.

Results

Results indicated that two gray matter networks (GM-05 and GM-23) and one white matter network (WM-25) differed between the OCPD and the control group. GM-05 included brain regions belonging to the Default Mode Network and the Salience Network and was significantly correlated with anxiety; GM-23 included portions of the cerebellum, the precuneus, and the fusiform gyrus; WM-25 included white matter portions adjacent to Default Mode Network regions.

Discussion

These findings shed new light on the gray and white matter contributions to OCPD and may pave the way to developing objective markers of this disorder.

Multimodal neuroimaging investigation of post-stroke fatigue in middle-aged and older adults: combining resting-state fMRI and DTI-ALPS analysis

Background

Post-stroke fatigue (PSF) is a prevalent but often overlooked complication, particularly in middle-aged and older stroke survivors. Neuroimaging studies exploring the neural mechanisms of PSF in this age group are limited. This study aimed to identify imaging markers for PSF in middle-aged and older adults using a multimodal imaging approach.

Methods

This retrospective case-control study analyzed data from patients with first ischemic stroke aged 50 years and above who were treated from January 2021 to June 2022 at the First Hospital of the University of Science and Technology of China. PSF was assessed using the Fatigue Severity Scale (FSS) and diagnostic criteria. All patients underwent resting-state functional MRI (rs-fMRI) and diffusion tensor imaging along perivascular space (DTI-ALPS) to assess brain functional connectivity and glymphatic system function.

Results

The PSF group (mean age 62.7 ± 10.50 years) showed reduced global functional connectivity compared to non-fatigued controls (mean age 58.40 ± 9.20 years) (p < 0.05, FDR corrected), with enhanced connectivity between the insula and right inferior frontal gyrus. DTI-ALPS analysis revealed a negative correlation between DTI-ALPS index and fatigue severity (R2 = 0.40, p < 0.001) in the PSF group, suggesting an association between impaired glymphatic clearance and fatigue symptoms in middle-aged and older stroke survivors.

Conclusion

This multimodal neuroimaging study highlights altered brain functional connectivity and glymphatic dysfunction as potential neural correlates of PSF in middle-aged and older adults. The findings provide novel insights into the complex pathophysiology of PSF in the aging brain, implicating both functional brain networks and the glymphatic system. Further research is warranted to validate these age-specific findings and explore targeted interventions for PSF in older stroke survivors.

Decoupling of Neurochemical and White Matter Microstructural Integrity in Posterior Cingulate Cortex Predicts Early Alzheimer's Disease Progression

Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by early metabolic and structural brain changes. These alterations are often detectable during mild cognitive impairment due to AD (AD-MCI), a prodromal stage of the disease. The posterior cingulate cortex (PCC), a critical brain region involved in memory and self-referential processing, is particularly vulnerable to these changes. We recruited 21 healthy controls (HC) and 20 AD-MCI patients to participate in this study. Point-Resolved Echo Spin Spectroscopy (PRESS) combined with MEGA-PRESS was employed to accurately measure levels of Gamma-Aminobutyric Acid (GABA) and Glx (Combination of Glutamate and Glutamine) in the PCC. Additionally, diffusion tensor imaging (DTI) was utilized to assess white matter (WM) microstructure integrity. Key metabolites, including N-acetylaspartate (NAA), choline (Cho), and myo-inositol (mI), were quantified to provide insights into neuronal health and metabolic status, while WM integrity was evaluated using fractional anisotropy (FA) and mean diffusivity (MD) metrics. In the PCC, AD-MCI patients exhibited a significant reduction in tNAA/tCr (1.22 ± 0.09 vs. HC 1.32 ± 0.07, p < 0.001) and NAA/mI (1.22 ± 0.12 vs. HC 1.44 ± 0.12, p < 0.001), along with an increase in mI/Cr (1.84 ± 0.28 vs. HC 1.60 ± 0.29, p = 0.012) and decreased GABA+/water (2.23 ± 0.78 vs. HC 2.98 ± 0.73, p = 0.003). Diffusion metrics revealed higher mean diffusivity in PCC-connected gray matter (GM_MD: 10.40 ± 0.79 vs. 9.53 ± 0.80 × 10⁻⁴ mm²/s, p < 0.01) and white matter (WM_MD: 0.09 ± 0.01 vs. 0.08 ± 0.01 × 10⁻² mm²/s, p < 0.01). Notably, in AD-MCI, NAA/mI was negatively correlated with WM_MD (r = - 0.462, p = 0.047), and tNAA/tCr was positively correlated with WM_FA (r = 0.580, p = 0.009). PCC neurochemical-microstructural decoupling (NAA/mI-MD dissociation with preserved tNAA/tCr-FA coupling) marks early AD progression. This dissociation pattern, reflecting concurrent neuronal dysfunction and compensatory glial responses, proposes a novel multimodal biomarker for tracking axonal degeneration prior to overt cognitive decline.

Neuroticism and ethical risk perception among employees: Neurostructural correlates in the left precuneus

Prior research using psychometric measures has yielded mixed results regarding the relationship between neuroticism and ethical risk-taking. Considering the pivotal role of ethical risk perception in influencing both ethical risk-taking and broader organizational outcomes, it is essential to explore its connection with neuroticism and the neural mechanisms underlying this link. This study employed voxel-based morphometry analysis of structural MRI data to investigate the neural correlates of ethical risk perception, measured by gray matter volume (GMV), and its association with neuroticism in a sample of 214 healthy, full-time employees. Whole-brain regression analysis revealed a negative correlation between ethical risk perception and GMV in the left precuneus. Mediation analysis further identified GMV in the left precuneus as a mediator in the relationship between neuroticism and ethical risk perception, controlling for demographic factors, total GMV, and the other traits within the Big Five personality model. These findings offer valuable insights into the neurostructural underpinnings of ethical risk perception and highlight the critical role of GMV in the left precuneus in linking neuroticism with ethical risk perception, enhancing our understanding of the neural mechanisms driving risk decision-making in the ethical domain.

Neurophysiological features of dream recall and the phenomenology of dreams: Auditory stimulation impacts dream experiences

Studies on the electrophysiological and phenomenological aspects of dream experiences provide insight on consciousness during sleep. Whole night polysomnography (PSG) studies were conducted among 29 healthy young participants with high dream recall abilities. Dreams reports were collected during the second night by multiple awakening protocol. On the third night, participants were presented with an audiovisual task and during subsequent sleep, dream reports were collected following an auditory stimuli presentation. REM sleep dreams favor high dream recall rates when compared to N2 dreams. Enhanced EEG beta activity, functional connectivity across the brain structures of the default mode network (DMN) and activation of medial frontal cortex were observed during dream recall irrespective of the sleep states. Auditory stimulations influenced emotional dream experiences highlighting the possibility of target memory reactivation. The study highlights the potential role of dream states and dream experiences in understanding consciousness during sleep.

Breaking prolonged sitting with high-intensity interval training to improve cognitive and brain health in middle-aged and older adults: a protocol for the pilot feasibility HIIT2SITLess trial

INTRODUCTION

Excessive sedentary time (ST) is linked to dementia risk, poorer attentional control and episodic memory. These cognitive decrements have been associated with decreased functional connectivity (FC) in the frontoparietal network (FPN) and default mode networks (DMN) with ageing. Physical activity (PA) interventions can enhance FC in these networks, but these interventions are not designed to decrease ST among older adults. Prolonged sitting (ie, sitting continuously for ≥20 min) can acutely reduce frontoparietal brain function and attentional control, while a single PA bout lasting at least 20 min can enhance them. It has been theorised that stimulation of the cerebral norepinephrine release through peripheral increase in catecholamines may explain this effect. In contrast, the effects of shorter (<10 min) PA bouts used to interrupt prolonged sitting on neurocognitive functions remain poorly understood. This pilot randomised crossover feasibility trial capitalises on PA intensity as the major limiting factor in peripheral catecholamine increase and tests the effects of interrupting prolonged sitting every 30 min with 6 min high-intensity interval training (HIIT) compared with low-intensity interval training (LIIT) bouts. The study will address three aims: (1) to assess feasibility, acceptability, fidelity and safety of HIIT breaks to improve neurocognitive function in middle-aged and older adults; (2) to quantify the differences between conditions in the change in the amplitude and latency of the P3b component of event-related potentials (a marker for frontoparietal function) and (3) to explore the differences between conditions in attentional control, episodic memory and FC of the FPN and DMN in middle-aged and older adults.

METHODS AND ANALYSIS

54 healthy adults, aged 40-75 years, will be recruited from the local community and randomly assigned to a condition sequence (HIIT, LIIT vs LIIT and HIIT). Each HIIT bout comprises a 1 min warm-up, 2 min at 90% of the maximum heart rate (HRmax), 1 min passive rest and 2 min at 90% HRmax. During 2 min intervals in LIIT, participants exercise at 57%-60% of HRmax. The primary outcomes include the feasibility (recruitment and retention rates, percentage of valid electroencephalogram data), acceptability of time commitment, HIIT bouts and neurocognitive assessments, fidelity (the intensity of HIIT breaks, percentage of time spent sitting) and the amplitude and the latency of the P3b component of event-related brain potentials measured during the modified Eriksen flanker task at pretests, after the first and the third PA bout and at post-test. General linear mixed-effects models will be used to test the effects of the intervention on the P3b component.

ETHICS AND DISSEMINATION

The Institutional Review Board at the University of Illinois Urbana-Champaign provided the ethical approval for the study. Findings will be disseminated in peer-reviewed journals and at scientific conferences.

TRIAL REGISTRATION NUMBER

NCT06243016.

Disruptive resting state networks characterizing depressive comorbidity in Alzheimer's disease and mild cognitive impairment

BackgroundDepressive comorbidity in neurodegeneration has been shown to predict conversion from mild cognitive impairment (MCI) to Alzheimer's disease (AD). However, its pathophysiology is not completely understood.ObjectiveHere, we characterize aberrant functional resting state networks (RSNs) characterizing depressive comorbidity in both AD and MCI.MethodsWe conducted a systematic literature review on Scopus, PubMed, and Web of Science to extract experiments that compared resting state scans of depressed and non-depressed MCI or AD patients. We employed Activation Likelihood Estimation (ALE) meta-analysis on eligible studies resulting from the search, to describe regions of significant co-activation across studies.ResultsThe systematic search resulted in 17 experiments, with 303 participants in total. The ALE yielded 10 clusters of significant co-activation distributed in the five major RSNs and across cortico-basal ganglia-thalamic circuits.ConclusionsDepressive comorbidity in neurodegeneration presents signature aberrant resting-state fluctuations. Understanding these within- and between-network alterations may be useful for future diagnostic and therapeutic applications.

Probing the Neurodynamic Mechanisms of Cognitive Flexibility in Depressed Individuals with Autism Spectrum Disorder

Introduction: Autism spectrum disorder (ASD) is characterized by deficits in social behavior and executive function (EF), particularly in cognitive flexibility. Whether transcranial magnetic stimulation (TMS) can improve cognitive outcomes in patients with ASD remains an open question. We examined the acute effects of prefrontal TMS on cortical excitability and fluid cognition in individuals with ASD who underwent TMS for refractory major depression. Methods: We analyzed data from an open-label pilot study involving nine participants with ASD and treatment-resistant depression who received 30 sessions of accelerated theta burst stimulation of the dorsolateral prefrontal cortex, either unilaterally or bilaterally. Electroencephalography data were collected at baseline and 1, 4, and 12-weeks posttreatment and analyzed using a mixed-effects linear model to assess changes in regional cortical excitability using three models of spectral parametrization. Fluid cognition was measured using the National Institutes of Health Toolbox Cognitive Battery. Results: Prefrontal TMS led to a decrease in prefrontal cortical excitability and an increase in right temporoparietal excitability, as measured using spectral exponent analysis. This was associated with a significant improvement in the NIH Toolbox Fluid Cognition Composite score and the Dimensional Change Card Sort subtest from baseline to 12 weeks posttreatment (t = 3.79, p = 0.005, n = 9). Improvement in depressive symptomatology was significant (HDRS-17, F (3, 21) = 28.49, p < 0.001) and there was a significant correlation between cognitive improvement at week 4 and improvement in depression at week 12 (r = 0.71, p = 0.05). Conclusion: These findings link reduced prefrontal excitability in patients with ASD and improvements in cognitive flexibility. The degree to which these mechanisms can be generalized to ASD populations without Major Depressive Disorder remains a compelling question for future research.

Loneliness and social conformity: A predictive processing perspective

For social creatures like humans, loneliness-which is characterized by a perceived lack of meaningful social relationships-can result in detrimental health outcomes, especially when experienced over an extended period of time. One potential way to pursue rewarding social connections could be social conformity, the tendency to align one's behavior and opinions to those of others. In this perspective article, we give a broad overview of common and distinct neural mechanisms underlying loneliness and social conformity, and the involvement of the oxytocinergic system therein. Additionally, we consider how loneliness can be understood within a predictive processing framework. Specifically, negative expectations could be related to altered representations of the self and others in the medial prefrontal cortex, whereas diminished bottom-up signals from the insula may contribute to reduced precision in the perception of the social environment. This negatively skewed internal model may perpetuate loneliness and lead to chronicity over time. While acute isolation and loneliness could drive people toward reconnection and increased social conformity, chronic loneliness may lead to distrust and avoidance, eventually resulting in nonconformity. We suggest different mediating mechanisms and moderating factors that warrant further investigation in future research.

The Relationship of glutamate signaling to cannabis use and schizophrenia

PURPOSE OF REVIEW

This review examines the literature associating cannabis with schizophrenia, glutamate dysregulation in schizophrenia, and cannabis involvement in glutamate pathways. Cannabis use is widespread among adolescents world-wide and is sold legally in many countries for recreational use in a variety of forms. Most people use it without lasting effects, but a portion of individuals have negative reactions that manifest in acute psychotic symptoms, and in some, symptoms continue even after the use of cannabis has ceased. To date, there is a huge gap in our understanding of why this occurs.

RECENT FINDINGS

Recent studies have focused on abnormalities in the glutamate pathway in schizophrenia, the effect of cannabis on the glutamate system, and the role of glutamate in the brain Default Mode Network.

SUMMARY

Given these observations, we hypothesize that perturbance of glutamate neuronal connectivity by cannabis in the brains of individuals genetically at high risk for psychosis will initiate a schizophrenia-like psychosis. Future studies may tie together these diverse observations by combining magnetic resonance spectroscopy (MRS) and functional magnetic resonance imaging (fMRI) of the default resting state network in patients with new onset schizophrenia who do and do not use cannabis compared with nonpsychotic individuals who do and do not use cannabis.

Functional connectivity across multi-frequency bands in patients with tension-type headache: a resting-state fMRI retrospective study

OBJECTIVES

Tension-type headache (TTH) is the most common nervous system disorder worldwide. This study aimed to examine abnormal network-level brain functional connectivity (FC) alterations in patients with TTH across multi-frequency bands.

METHODS

The study enrolled 63 subjects, comprising 32 patients with TTH and 31 healthy controls (HC). According to our team's previous research, the brain regions with abnormal ReHo in the conventional frequency band (0.01-0.08 Hz) and the slow-5 band (0.01-0.027 Hz) were chosen as seed regions of interest (ROIs). Subsequently, the FC between ROIs and the entire brain analysis across various frequency bands was calculated to evaluate network-level alterations, and differences between the TTH and HC were analyzed. Pearson's correlation analysis was conducted to assess the relationship between significantly altered FC values in two frequency bands and visual analog score (VAS) in TTH patients.

RESULTS

In the slow-5 band (0.01-0.027 Hz), FC between right medial superior frontal gyrus and right medial temporal pole/right inferior temporal gyrus as well as right middle frontal gyrus and left supramarginal gyrus of TTH patients exhibited significantly higher, compared to the HC group, while FC between right middle frontal gyrus and right lateral occipital cortex reduced. For the correlation results, there was no correlation between abnormal brain regions of FC and VAS score.

CONCLUSIONS

Changes in FC within brain regions associated with TTH are linked to pain processing. And the altered FC in TTH patients were frequency dependent. These initial observations could enhance our understanding of TTH's pathophysiological mechanism and offer insights for its future diagnosis and treatment.

Aging-dependent loss of functional connectivity in a mouse model of Alzheimer's disease and reversal by mGluR5 modulator

Amyloid accumulation in Alzheimer's disease (AD) is associated with synaptic damage and altered connectivity in brain networks. While measures of amyloid accumulation and biochemical changes in mouse models have utility for translational studies of certain therapeutics, preclinical analysis of altered brain connectivity using clinically relevant fMRI measures has not been well developed for agents intended to improve neural networks. Here, we conduct a longitudinal study in a double knock-in mouse model for AD (AppNL-G-F/hMapt), monitoring brain connectivity by means of resting-state fMRI. While the 4-month-old AD mice are indistinguishable from wild-type controls (WT), decreased connectivity in the default-mode network is significant for the AD mice relative to WT mice by 6 months of age and is pronounced by 9 months of age. In a second cohort of 20-month-old mice with persistent functional connectivity deficits for AD relative to WT, we assess the impact of two-months of oral treatment with a silent allosteric modulator of mGluR5 (BMS-984923/ALX001) known to rescue synaptic density. Functional connectivity deficits in the aged AD mice are reversed by the mGluR5-directed treatment. The longitudinal application of fMRI has enabled us to define the preclinical time trajectory of AD-related changes in functional connectivity, and to demonstrate a translatable metric for monitoring disease emergence, progression, and response to synapse-rescuing treatment.

The self-awareness brain network: Construction, characterization, and alterations in schizophrenia and major depressive disorder

Self-awareness (SA) research is crucial for understanding cognition, social behavior, mental health, and education, but SA's underlying network architecture, particularly connectivity patterns, remains largely uncharted. We integrated meta-analytic findings with connectivity-behavior correlation analyses to systematically identify SA-related regions and connections in healthy adults. Edge-weighted networks capturing public, private, and composite SA dimensions were established, where weights represented correlation strengths between tractography-derived structural connectivities and SA levels quantified through behavioral assessments. Then, multilevel SA networks were extracted across a spectrum of correlation thresholds. Robust full-threshold analyses revealed their hierarchical continuum encompassing distinct lateralization patterns, topological transitions, and characteristic hourglass-like architectures. Pathological analysis demonstrated SA connectivity disruptions in schizophrenia (SZ) and major depressive disorder (MDD): approximately 40 % of SA-related connectivities were altered in SZ and 20 % in MDD, with 90 % of MDD alterations overlapping with SZ. While disease-specific and shared alterations were also observed in network-level topological properties, the core SA connectivity framework remained preserved in both disorders. Collectively, these findings significantly advanced our understanding of SA's neurobiological substrates and their pathological deviations.

Multi-Metric Approach for the Comparison of Denoising Techniques for Resting-State fMRI

Despite the increasing use of resting-state functional magnetic resonance imaging (rs-fMRI) data for studying the spontaneous functional interactions within the brain, the achievement of robust results is often hampered by insufficient data quality and by poor knowledge of the most effective denoising methods. The present study aims to define an appropriate denoising strategy for rs-fMRI data by proposing a robust framework for the quantitative and comprehensive comparison of the performance of multiple pipelines made available by the newly proposed HALFpipe software. This will ultimately contribute to standardizing rs-fMRI preprocessing and denoising steps. Fifty-three participants took part in the study by undergoing a rs-fMRI session. Synthetic rs-fMRI data from one subject were also generated. Nine different denoising pipelines were applied in parallel to the minimally preprocessed fMRI data. The comparison was conducted by computing previously proposed and novel metrics that quantify the degree of artifact removal, signal enhancement, and resting-state network identifiability. A summary performance index, accounting for both noise removal and information preservation, was proposed. The results confirm the performance heterogeneity of different denoising pipelines across the different quality metrics. In both real and synthetic data, the summary performance index favored the denoising strategy including the regression of mean signals from white matter and cerebrospinal fluid brain areas and global signal. This pipeline resulted in the best compromise between artifact removal and preservation of the information on resting-state networks. Our study provided useful methodological tools and key information on the effectiveness of multiple denoising strategies for rs-fMRI data. Besides providing a robust comparison approach that could be adapted to other fMRI studies, a suitable denoising pipeline for rs-fMRI data was identified, which could be used to improve the reproducibility of rs-fMRI findings.

An interaction-centric approach for quantifying eye-to-eye reciprocal interaction

This study presents an interaction-centric framework for analytically investigating brain-to-brain dynamics during eye contact, advancing beyond the traditional spectator model. The foundation of the interactor approach is to delineate the interaction. To achieve this, simultaneous brain activity engaged in eye contact was captured using hyperscanning fMRI. The BOLD responses were first divided into eye-to-eye reciprocal interaction and eye-to-face non-reciprocal communication based on the experimental design; then the reciprocal interaction response was further differentiated into sensory-based (exogenous) and mind-based (endogenous) components to characterize agentic interaction. The proposed interactor approach not only determines interaction from dyadic brain states but also computes emergent interactive brain states arising from the interaction. To achieve these, reciprocal interactive fMRI responses were quantified into an interaction matrix, from which interaction-induced communication channels were identified using Correspondence Analysis, and information flow within those channels was measured with Mutual Information. The advantage of the interactor approach is its ability to reveal emergent dyadic brain states that a spectator approach cannot fully unravel. When applied to parent-child eye contact, this method confirmed existing developmental findings, clarified previous inconsistencies, and uncovered new insights into how reciprocal social engagement shapes brain function.

General anaesthesia decreases the uniqueness of brain functional connectivity across individuals and species

The human brain is characterized by idiosyncratic patterns of spontaneous thought, rendering each brain uniquely identifiable from its neural activity. However, deep general anaesthesia suppresses subjective experience. Does it also suppress what makes each brain unique? Here we used functional MRI scans acquired under the effects of the general anaesthetics sevoflurane and propofol to determine whether anaesthetic-induced unconsciousness diminishes the uniqueness of the human brain, both with respect to the brains of other individuals and the brains of another species. Using functional connectivity, we report that under anaesthesia individual brains become less self-similar and less distinguishable from each other. Loss of distinctiveness is highly organized: it co-localizes with the archetypal sensory-association axis, correlating with genetic and morphometric markers of phylogenetic differences between humans and other primates. This effect is more evident at greater anaesthetic depths, reproducible across sevoflurane and propofol and reversed upon recovery. Providing convergent evidence, we show that anaesthesia shifts the functional connectivity of the human brain closer to the functional connectivity of the macaque brain in a low-dimensional space. Finally, anaesthesia diminishes the match between spontaneous brain activity and cognitive brain patterns aggregated from the Neurosynth meta-analytic engine. Collectively, the present results reveal that anaesthetized human brains are not only less distinguishable from each other, but also less distinguishable from the brains of other primates, with specifically human-expanded regions being the most affected by anaesthesia.

Brain reactivity to nicotine cues mediates the link between resting-state connectivity and cue-induced craving in individuals who smoke or vape nicotine

Individual differences in brain intrinsic functional connectivity (FC) and reactivity to nicotine cues are linked to variability in clinical outcomes in nicotine dependence. However, the relative contributions and potential interdependencies of these brain imaging-derived phenotypes in the context of craving and nicotine dependence are unclear. Moreover, it is unknown whether these relationships differ in individuals who smoke versus vape nicotine. To investigate these questions, eighty-six individuals who use nicotine daily (n = 67 smoking, n = 19 vaping) completed either a smoking or vaping cue-reactivity task and a resting-state scan during functional magnetic resonance imaging (fMRI). Validating the efficacy of the smoking and vaping tasks, both cohorts displayed robust reactivity to nicotine versus neutral cues in the default mode network (DMN) and the anterior insula (AI), a primary node of the salience network (SN), which did not habituate over time. In the smoking and vaping groups, lower prefrontal reactivity to nicotine versus neutral cues and greater resting-state FC between nodes of the SN and DMN were associated with higher cue-induced craving. Moreover, we found that the former partially mediated the latter, suggesting a mechanism in which high resting SN-DMN connectivity increases craving susceptibility partly via a constraining effect on regulatory prefrontal reactivity to cues. These relationships were not impacted by group, suggesting that links between brain function and craving are similar regardless of smoking or vaping nicotine.

Culture and Behaviour Management of Children in the Dental Clinic: A Scoping Review

Cultural norms, beliefs, and practices influence parental expectations, children's responses, and the acceptance of behaviour management techniques (BMTs) in paediatric dentistry. Despite this, the existing guidelines often adopt a standardized approach, overlooking critical cultural differences. This scoping review maps the links between culture and behaviour management strategies in paediatric dental settings. A scoping review following PRISMA guidelines was conducted across PubMed, Cochrane Library, Web of Science, Google Scholar, and hand-searched sources from the inception of the databases to 31 January 2025. A total of 671 studies were identified, with 15 meeting the inclusion criteria. Data on the key findings were inductively analyzed to assess cultural influences on parental acceptance, child behavior, and communication. The findings show that non-invasive BMTs such as TellShow-Do and positive reinforcement were the most accepted across cultures, while passive and active restraints were least accepted, especially in Western populations. Parental preferences varied; Jordanian parents were more accepting of passive restraint than German parents, while general anaesthesia was preferred in Bahrain. Cultural norms shaped communication styles-Latino families emphasized warm interpersonal interactions, whereas Pakistani families exhibited limited parental involvement due to language barriers. Black and Hispanic Medicaid-enrolled mothers in the U.S. reported lower satisfaction with pain management, highlighting disparities in culturally competent care. In conclusion, cultural factors significantly influence paediatric behaviour management in dental clinics. Integrating cultural competence into practice can enhance communication, improve patient compliance, and promote equitable care. Further research is needed, particularly in Africa and South America, to inform globally inclusive behaviour management guidelines.

Investigating the associations between tau and mental orientation among cognitively unimpaired individuals

BackgroundImpairments in orientation in space, time, and person occur frequently in Alzheimer's disease (AD) dementia. Subtle changes in orientation may arise in preclinical and prodromal disease stages. Thus, assessing orientation may help identify those on a trajectory toward AD dementia.ObjectiveTo investigate how orientation, measured using a novel artificial intelligence-based paradigm, relates to AD biomarkers (amyloid and tau) in cognitively unimpaired older adults.MethodsUsing an automated chatbot, 53 cognitively unimpaired participants (74.0 ± 5.5 years; 60% female) provided details about memories and relationships, recognition of historical event dates, and geographical locations. These details were then used to assess orientation to space, time, and person. For each domain separately, orientation accuracy was calculated by dividing the number of correct responses by response time. All participants underwent Pittsburgh compound-B (amyloid) and flortaucipir (tau) positron emission tomography. We analyzed the relationship between performance on the three orientation domains and retrosplenial, precuneus, neocortical, and medial temporal tau, and global amyloid.ResultsHigher retrosplenial and precuneus tau burden were associated with worse temporal orientation (β = -0.32, 95% confidence interval [95%CI] = [-0.59, -0.05] and β = -0.29, 95%CI = [-0.57, -0.01], respectively). Spatial or social orientation were not associated with amyloid or tau.ConclusionsThese results suggest that impaired temporal orientation is related to AD pathological processes, even before the onset of overt cognitive impairment, and may infer a role for personalized assessment of orientation in early diagnosis of AD.

Neural correlates of subjective cognitive decline in Alzheimer's disease: a systematic review of structural and functional brain changes for early diagnosis and intervention

Background

Subjective Cognitive Decline (SCD) is increasingly recognized as a preclinical stage of Alzheimer's disease (AD), representing a critical window for early detection and intervention. Understanding the structural and functional neural changes in SCD can improve diagnosis, monitoring, and management of this early stage of disease.

Methods

A systematic review was conducted using PubMed, Web of Science, and Scopus databases to identify studies examining neuroanatomical, neurofunctional, and neuroimaging findings in individuals with SCD. Inclusion criteria emphasized studies exploring SCD's potential as an early biomarker for AD progression.

Results

A total of 2.283 studies were screened, with 17 meeting the inclusion criteria. Evidence indicates that SCD is associated with cortical thinning and reductions in gray matter volume (GMV), particularly in the hippocampus, entorhinal cortex, and medial temporal lobe. Functional imaging studies reveal disruptions in the default mode network (DMN), executive control networks (ECN), and sensorimotor networks (SMN), indicating both compensatory mechanisms and early dysfunction. Dynamic functional connectivity studies report reduced brain activity efficiency, while graph theory analyses show decreased network integration. Advanced neuroimaging techniques and machine learning (ML) approaches demonstrate significant promise in detecting subtle neural changes in SCD, with applications for early diagnosis and monitoring disease progression.

Conclusion

SCD represents a heterogeneous condition characterized by mixed compensatory and degenerative neural changes, marking a critical early stage in the AD continuum. Combining structural and functional brain alterations with advanced neuroimaging and ML methodologies provides valuable biomarkers for early detection. Future longitudinal and multimodal studies are essential to standardize methodologies, account for individual variability, and develop personalized interventions aimed at mitigating progression to dementia.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42024616052, CRD42024616052.

Alterations in degree centrality and functional connectivity associated with cognitive Impairment in myotonic dystrophy type 1:A Preliminary functional MRI study

OBJECTIVES

The study aimed to examine alterations in voxel-based degree centrality (DC) and functional connectivity (FC), and their relationship with cognitive impairments in patients with myotonic dystrophy type 1 (DM1).

METHODS

Eighteen DM1 patients and eighteen healthy controls participated in the study and were assessed using a comprehensive neuropsychological battery. Voxel-wise DC and FC analyses were used to assess abnormalities in functional connections among aberrant hubs. Correlational analyses were used to identify and explore the relationship between DC and FC values and cognitive performance in DM1 patients.

RESULTS

DM1 patients exhibited reduced DC in the bilateral Rolandic operculum, left inferior frontal gyrus (triangular part), right angular gyrus, right median cingulate and paracingulate gyri, and right middle temporal gyrus. Conversely, increased DC was observed in the right fusiform gyrus, right hippocampus and left inferior temporal gyrus. FC analysis revealed that altered connectivity predominantly occurred among the right middle temporal gyrus, right angular gyrus and left inferior frontal gyrus (triangular part). DC value in left inferior temporal gyrus showed significant correlations with scores from the Digital Span Test-Forward (r = -0.556, p = 0.025), the Digital Span Test -Backward (r = -0.588, p = 0.017), the Auditory Verbal Learning Test (r = -0.586, p = 0.017) and the Rey-Osterrieth Complex Figure test (copying version) (r = 0.536, p = 0.032) in DM1 patients. No significant correlations were discovered between FC values and neurocognitive performances.

CONCLUSION

The study demonstrated that abnormalities in DC and FC may become potential neuroimaging biomarkers for cognitive decline in DM1 patients.

Differential brainstem connectivity according to sex and menopausal status in healthy male and female individuals

BACKGROUND

Brainstem nuclei play a critical role in both ascending monoaminergic modulation of cortical function and arousal, and in descending bulbospinal pain modulation. Even though sex-related differences in the function of both systems have been reported in animal models, a complete understanding of sex differences, as well as menopausal effects, in brainstem connectivity in humans is lacking. This study evaluated resting-state connectivity of the dorsal raphe nucleus, right and left locus coeruleus complex (LCC), and periaqueductal gray (PAG) according to sex and menopausal status in healthy individuals. In addition, relationships between systemic estrogen levels and brainstem-network connectivity were examined in a subset of participants.

METHODS

Resting-state fMRI was performed in 47 healthy male (age, 31.2 ± 8.0 years), 53 healthy premenopausal female (age, 24.7 ± 7.3 years; 22 in the follicular phase, 31 in the luteal phase), and 20 postmenopausal female participants (age, 54.6 ± 7.2 years). Permutation Analysis of Linear Models (5000 permutations) was used to evaluate differences in brainstem-network connectivity according to sex and menopausal status, controlling for age. In 10 males and 17 females (9 premenopausal; 8 postmenopausal), estrogen and estrogen metabolite levels in plasma and stool were determined by liquid chromatography-mass spectrometry/mass spectrometry. Relationships between estrogen levels and brainstem-network connectivity were evaluated by partial least squares analysis.

RESULTS

Left LCC-executive control network connectivity showed an overall sex difference (p = 0.02), with higher connectivity in females than in males; however, this was mainly due to differences between males and premenopausal females (p = 0.008). Additional sex differences were dependent on menopausal status: PAG-default mode network (DMN) connectivity was higher in postmenopausal females than in males (p = 0.04), and PAG-sensorimotor network (SMN) connectivity was higher in premenopausal females than in males (p = 0.03) and postmenopausal females (p = 0.007). Notably, higher free 2-hydroxyestrone levels in stool were reliably associated with higher PAG-SMN and PAG-DMN connectivity in premenopausal females (p < 0.01).

CONCLUSIONS

Healthy females show higher brainstem-network connectivity involved in cognitive control, sensorimotor function, and self-relevant processes than males, dependent on their menopausal status. Further, 2-hydroxyestrone, implicated in pain, may modulate PAG connectivity in premenopausal females. These findings may relate to differential vulnerabilities to chronic stress-sensitive disorders at different life stages.

Charting brain functional development from birth to 6 years of age

Early childhood is crucial for brain functional development. Using advanced neuroimaging methods, characterizing functional connectivity has shed light on the developmental process in infants. However, insights into spatiotemporal functional maturation from birth to early childhood are substantially lacking. In this study, we aggregated 1,091 resting-state functional MRI scans of typically developing children from birth to 6 years of age, harmonized the cohort and imaging-state-related bias, and delineated developmental charts of functional connectivity within and between canonical brain networks. These charts revealed potential neurodevelopmental milestones and elucidated the complex development of brain functional integration, competition and transition processes. We further determined that individual deviations from normative growth charts are significantly associated with infant cognitive abilities. Specifically, connections involving the primary, default, control and attention networks were key predictors. Our findings elucidate early neurodevelopment and suggest that functional connectivity-derived brain charts may provide an effective tool to monitor normative functional development.

Resting state brain network segregation is associated with walking speed and working memory in older adults

Older adults exhibit larger individual differences in walking ability and cognitive function than young adults. Characterizing intrinsic brain connectivity differences in older adults across a wide walking performance spectrum may provide insight into the mechanisms of functional decline in some older adults and resilience in others. Thus, the objectives of this study were to: (1) determine whether young adults and high- and low-functioning older adults show group differences in brain network segregation, and (2) determine whether network segregation is associated with working memory and walking function in these groups. The analysis included 21 young adults and 81 older adults. Older adults were further categorized according to their physical function using a standardized assessment; 54 older adults had low physical function while 27 were considered high functioning. Structural and functional resting state magnetic resonance images were collected using a Siemens Prisma 3T scanner. Working memory was assessed with the NIH Toolbox list sorting test. Walking speed was assessed with a 400 m walk test at participants' self-selected speed. We found that network segregation in mobility-related networks (sensorimotor, vestibular) was higher in older adults with higher physical function compared to older adults with lower physical function. There were no group differences in laterality effects on network segregation. We found multivariate associations between working memory and walking speed with network segregation scores. The interaction of left sensorimotor network segregation and age groups was associated with higher working memory function. Higher left sensorimotor, left vestibular, right anterior cingulate cortex, and interaction of left anterior cingulate cortex network segregation and age groups were associated with faster walking speed. These results are unique and significant because they demonstrate higher network segregation is largely related to higher physical function and not age alone.

Causal effect of three autoimmune diseases on brain functional networks and cerebrospinal fluid metabolites to underlie the pathogenesis of autoimmune psychosis: a two-sample mendelian randomization analysis

BACKGROUND

Autoimmune diseases such as Systemic Lupus Erythematosus (SLE), Sjögren's Syndrome (SS), and Hashimoto's Thyroiditis (HT) frequently exhibit neuropsychiatric manifestations, including cognitive impairment, depression, anxiety, and so on, yet the exact pathogenesis underlying this association remain incompletely understood. Dysfunction of brain resting-state functional networks and cerebrospinal fluid (CSF) metabolite disturbances have been widely reported in psychiatric disorders. However, the application of resting-state functional magnetic resonance imaging (rsfMRI) and CSF metabolomics in the diagnosis and monitoring of autoimmune psychosis is still limited.

METHODS

A two-sample Mendelian randomization (MR) analysis was performed to investigate the causal relationships between three autoimmune diseases (SLE, SS, and HT, n = 14,267 to 402,090 individuals) and 191 rsfMRI phenotypes (n = 47,276 individuals), as well as 338 CSF metabolites. The genome-wide association study (GWAS) of three autoimmune diseases was used as the exposure, whereas rsfMRI phenotypes and 338 CSF metabolites were treated as the outcome. Inverse variance weighted (IVW) with P value < 0.05 was regarded as the primary approach for calculating causal estimates. Additionally, the false discovery rate (FDR)-adjusted P value (PFDR) < 0.05 was utilized to account for multiple testing. MR Egger method, weighted median method, simple mode method and weighted mode method were used for sensitive analysis.

RESULTS

Our analyses identified 5 causal relationships between SLE and the 191 rsfMRI phenotypes, 48 between SS and the 191 rsfMRI phenotypes, and 4 between HT and the 191 rsfMRI phenotypes. Additionally, we found 8 causal relationships between HT and CSF metabolites. Furthermore, all three diseases were significantly associated with the temporal lobe and triple networks (default mode network (DMN), salience network (SN), and central executive network (CEN)), which are the core brain regions and functional networks for cognition. Following FDR correction, 6 causal relationships between SS and the 191 rsfMRI phenotypes were further validated.

CONCLUSIONS

Our study pinpoints important brain functional networks and CSF metabolites potentially implicated in the pathogenesis of psychiatric disorders associated with autoimmune diseases and highlights critical brain regions for the development of novel therapeutics.