Most recent paper

Front Psychol. 2025 Feb 4;15:1405425. doi: 10.3389/fpsyg.2024.1405425. eCollection 2024.

ABSTRACT

INTRODUCTION: Most studies of dyslexia focus on domains of impairment (e.g., reading and phonology, among others), but few examine possible strengths. In the present study, we investigated semantic fluency as a cognitive strength in English-speaking children with dyslexia aged 8-13.

METHODS: Ninety-seven children with dyslexia completed tests of letter and semantic verbal fluency, standardized measures of reading and cognitive functions, and task-free resting-state functional magnetic resonance imaging (rs-fMRI). First, we adjusted performance on semantic fluency by letter fluency and created a residual score that was used to separate participants into high (residual >0) or average (residual <0) semantic performance groups. We then employed a psycholinguistic clustering and switching approach to the semantic fluency task and performed dynamic task-free rs-fMRI connectivity analysis to reveal group differences in brain dynamics.

RESULTS: High and average semantic fluency groups were well-matched on demographics and letter fluency but differed on their psycholinguistic patterns on the semantic fluency task. The high semantic fluency group, compared to the average semantic fluency group, produced a higher number of words within each cluster, a higher max cluster size, and a higher number of switches. Differential dynamic rs-fMRI connectivity (shorter average dwell time and greater brain state switches) was observed between the high and average groups in a large-scale bilateral frontal-temporal-occipital network.

DISCUSSION: These data demonstrate that a subgroup of children with dyslexia perform above average on semantic fluency tasks and their performance is strongly linked to distinct psycholinguistic patterns and differences in a task-free resting-state brain network, which includes regions previously implicated in semantic processing. This work highlights that inter-individual differences should be taken into account in dyslexia and reveals a cognitive area of strength for some children with dyslexia that could be leveraged for reading interventions.

PMID:39967994 | PMC:PMC11832474 | DOI:10.3389/fpsyg.2024.1405425

Int J Ophthalmol. 2025 Feb 18;18(2):297-307. doi: 10.18240/ijo.2025.02.14. eCollection 2025.

ABSTRACT

AIM: To analyze whether alterations of voxel mirror homology connectivity (VMHC) values, as determined by resting-state functional magnetic resonance imaging (rs-fMRI), occur in cerebral regions of patients with hypertensive retinopathy (HR) and to determine the relationship between VMHC values and clinical characteristics in patients with HR.

METHODS: Twenty-one patients with HR and 21 age-matched healthy controls (HCs) were assessed by rs-fMRI scanning. The functional connectivity between the hemispheres of the cerebrum was assessed by measuring VMHC, with the ability of VMHC to distinguish between the HR and HC groups assessed using receiver operating characteristic (ROC) curve analysis. Differences in the demographic and clinical characteristics of the HR and HC groups were analyzed by independent sample t-tests. The relationship between average VMHC in several brain areas of HR patients and clinical features was determined using Pearson correlation analysis.

RESULTS: Mean VMHC values of the bilateral cuneus gyrus (BA19), bilateral middle orbitofrontal gyrus (BA47), bilateral middle temporal gyrus (BA39) and bilateral superior medial frontal gyrus (BA9) were lower in the HR than in the HC group.

CONCLUSION: VMHC values can predict the development of early HR, prevent the transformation of hypertensive microangiopathy, and provide useful information explaining the changes in neural mechanism associated with HR.

PMID:39967983 | PMC:PMC11754017 | DOI:10.18240/ijo.2025.02.14

Transl Psychiatry. 2025 Feb 19;15(1):58. doi: 10.1038/s41398-025-03282-x.

ABSTRACT

Bipolar disorder (BD) and unipolar depression (UD) are defined as distinct diagnostic categories. However, due to some common clinical and pathophysiological features, it is a clinical challenge to distinguish them, especially in the early stages of BD. This study aimed to explore the common and disease-specific connectivity patterns in BD and UD. This study was constructed over 181 BD, 265 UD and 204 healthy controls. In addition, an independent group of 90 patients initially diagnosed with major depressive disorder at the baseline and then transferred to BD with the episodes of mania/hypomania during follow-up, was identified as initial depressive episode BD (IDE-BD). All participants completed resting-state functional magnetic resonance imaging (R-fMRI) at recruitment. Both network-based analysis and graph theory analysis were applied. Both BD and UD showed decreased functional connectivity (FC) in the whole brain network. The shared aberrant network across groups of patients with depressive episode (BD, IDE-BD and UD) mainly involves the visual network (VN), somatomotor networks (SMN) and default mode network (DMN). Analysis of the topological properties over the three networks showed that decreased clustering coefficient was found in BD, IDE-BD and UD, however, decreased shortest path length and increased global efficiency were only found in BD and IDE-BD but not in UD. The study indicate that VN, SMN, and DMN, which involve stimuli reception and abstraction, emotion processing, and guiding external movements, are common abnormalities in affective disorders. The network separation dysfunction in these networks is shared by BD and UD, however, the network integration dysfunction is specific to BD. The aberrant network integration functions in BD and IDE-BD might be valuable diagnostic biomarkers.

PMID:39966397 | DOI:10.1038/s41398-025-03282-x

Brain Imaging Behav. 2025 Feb 18. doi: 10.1007/s11682-025-00982-2. Online ahead of print.

ABSTRACT

Lesions in the basal ganglia present different neuroimaging manifestations compared to other regions. The functional connectivity and white matter (WM) microstructural alterations in patients with left basal ganglia acute ischemic stroke (AIS) remain unknown. This study aimed to explore the alterations of functional connectivity and WM microstructure, as well as their relationship with cognitive performance in patients with left basal ganglia AIS. We acquired resting-state functional MRI (rs-fMRI) and diffusion kurtosis imaging (DKI) data from 41 individuals with left basal ganglia AIS and 41 healthy controls (HC). The degree centrality (DC) method was applied to calculate the functional connectivity and Tract-Based Spatial Statistics was employed to evaluate the voxel-based group differences of diffusion metrics for the values of fractional anisotropy (FA), mean diffusivity, axial diffusivity (AD), radial diffusivity, mean kurtosis (MK), axial kurtosis, and radial kurtosis (RK). AIS showed attenuated DC in the bilateral precuneus and enhanced DC in the left caudate nucleus, compared with HC. In AIS, DC in the left caudate nucleus correlated positively with the Montreal Cognitive Assessment (MoCA) score (r = 0.681, p < 0.05). AIS had significantly decreased FA, AD, MK, and RK in WM tracts, including the internal capsule (IC), genu of corpus callosum (CC), body of CC, left superior longitudinal fasciculus (SLF), left cerebral peduncle, left corticospinal tract, anterior corona radiata (ACR), and left cingulum gyrus (CG). The MK in a cluster including the body of CC, right IC, left cingulate, SLF, ACR, and left CG was also significantly negatively correlated with MoCA scores (r = -0.508, p < 0.05). This study revealed that left basal ganglia AIS not only disrupted the functional connectivity of the whole brain but also had a pervasive impact on the WM microstructure of the whole brain. These findings provide novel insights into the underlying neural mechanisms of early cognitive decline in patients after AIS.

PMID:39964657 | DOI:10.1007/s11682-025-00982-2

Childs Nerv Syst. 2025 Feb 18;41(1):116. doi: 10.1007/s00381-025-06774-9.

ABSTRACT

The role of connectivity in the function and development of the human brain has been intensely studied over the last two decades. These findings have begun to be translated to the clinical setting, particularly in the context of epilepsy. Determining connectivity in the epileptic brain can be challenging and is even more difficult in the pediatric patient. In pediatric epilepsy, resting-state functional magnetic resonance imaging (rs-fMRI) has emerged as a powerful method for determining connectivity. Resting-state fMRI is a non-invasive method of determining correlated activity (functional connectivity) between brain regions in a task-free manner. This modality is especially useful in the pediatric population as it can be done under sedation and requires minimal cooperation from the patient. Over the last decade, rs-fMRI has been increasingly used and studied in pediatric epilepsy. In this article, we review this recent work and discuss the current state of rs-fMRI in the diagnosis and management of the different pediatric epilepsy syndromes. We first provide an overview of rs-fMRI in practice, including the different methods of analysis. We then describe the connectivity findings in pediatric epilepsy that have been revealed by rs-fMRI and the current state of rs-fMRI use in practice. Finally, we discuss what rs-fMRI has revealed about postoperative changes in connectivity and provide several recommendations for future research.

PMID:39964613 | DOI:10.1007/s00381-025-06774-9

Front Nutr. 2025 Feb 3;12:1440373. doi: 10.3389/fnut.2025.1440373. eCollection 2025.

ABSTRACT

INTRODUCTION: Dietary interventions such as caloric restriction (CR) exert positive effects on brain health. Unfortunately, poor compliance hinders the success of this approach. A proposed alternative is resveratrol (Rsv), a CR-mimetic known to promote brain health. Direct comparison between the effects of Rsv and CR on brain health is lacking, with limited knowledge on their sex-specific effects. Therefore, we aimed to compare and unravel the sex-specific impact of these dietary interventions on spontaneous brain activity.

METHODS: Here, we used resting-state fMRI to investigate functional connectivity (FC) changes in five prominent resting-state brain networks (RSNs) in healthy 4 month old male and female F344 rats supplemented to either 40% CR or daily Rsv supplementation (10 mg/kg, oral) for the duration of 1 month.

RESULTS: Our results demonstrated a decreased body weight (BW) in CR rats, as well as an increase in body weight in male Rsv supplemented rats, compared to female Rsv supplemented rats, whereas this difference between sexes was not observed in the control or CR groups. Furthermore, we found that both CR or Rsv supplementation induce a female-specific decrease of FC between the subcortical network and hippocampal network, and between the subcortical network and lateral cortical network. Moreover, Rsv supplementation lowered FC within the hippocampal network and between the hippocampal and the default mode like network, the lateral cortical network and the sensory network-an effect not observed for the CR rats.

DISCUSSION: Our findings reveal that both CR and Rsv induce a similar female-specific decrease of FC in RSNs associated with memory and emotion, all the while CR and Rsv induce dissimilar changes in body weight and other within- and between-RSN FC measures. Altogether, this study provides insight into the effects and comparability of short-term CR and Rsv supplementation on brain connectivity within- and between-RSNs in both male and female F344 rats, providing a FC reference for future research of dietary effects.

PMID:39963669 | PMC:PMC11830597 | DOI:10.3389/fnut.2025.1440373

Front Neurosci. 2025 Feb 3;19:1531375. doi: 10.3389/fnins.2025.1531375. eCollection 2025.

ABSTRACT

INTRODUCTION: Ketamine demonstrates robust and rapidly occurring antidepressant effects in patients with difficult-to-treat major depressive disorder. Ketamine's antidepressant effects and its impact on functional networks in non-resistant forms of major depressive disorder are expected to provide valuable insight into ketamine's mechanism of action related to depression.

METHODS: This study employs an existing network model of major depressive disorder to investigate the effects of ketamine on resting state connectivity in a therapy-non-resistant major depressive disorder population. In a randomized, double-blind, placebo-controlled, cross-over study, 0.5 mg/kg racemic ketamine or 0.9%NaCl was administered intravenously in 16 MDD patients. We applied resting-state functional magnetic resonance imaging (rs-fMRI) to explore changes in functional brain connectivity directly at 50, 80 and 165 min (acute) and 24 h (delayed) following ketamine administration. A clinician-rated 10-item scale (MADRS) was administered at 165 min and 24 h after ketamine administration. Connections-of-interest (COIs) were based on the previously published corticolimbic-insular-striatalpallidal-thalamic (CLIPST) circuitry model of major depressive disorder.

RESULTS: Compared with placebo, ketamine significantly (p < 0.0014) reduced the mean (SD) MADRS total score from 21.2 (5.9) pre-dose to 10.3 (4.6) 24 h post-dose. At both acute (p < 0.0172) and delayed (p < 0.0488) time points, significant rs-fMRI connectivity changes occurred only in MDD-related COIs as proposed by the CLIPST model. No changes in functional connectivity were found in non-CLIPST connections.

DISCUSSION: This study demonstrates that ketamine specifically affects depression-related circuitry. Analyzing functional connectivity based on a neurocircuitry model of a specific CNS disease and drug action may be an effective approach that could result in a more targeted analysis in future pharmaco-fMRI studies in CNS drug development.

PMID:39963257 | PMC:PMC11830811 | DOI:10.3389/fnins.2025.1531375

Neuropsychopharmacology. 2025 Feb 17. doi: 10.1038/s41386-025-02058-7. Online ahead of print.

ABSTRACT

Craving in alcohol drinkers is often triggered by chemosensory cues, such as taste and smell, which are linked to brain network connectivity. This study aimed to investigate whether these brain connectivity patterns could predict alcohol intake in young adults. Resting-state fMRI data were obtained from the Human Connectome Project (HCP) Young Adult cohort, comprising 1003 participants. Functional connectomes generated from 100 independent components were analyzed, identifying significant connections correlated with taste and odor scores after applying a false discovery rate (FDR) correction using the Benjamini-Hochberg (BH) method. These significant connections were then utilized as predictors in general linear models for various alcohol intake metrics. The models were validated in an independent sample to assess their accuracy. The training sample (n = 702) and the validation sample (n = 117) showed no significant demographic differences. Out of 742 possible connections, 41 related to odor and 25 related to taste passed the significance threshold (P < 0.05) after FDR-BH correction. Notable predictors included visual-visual connectivity (node32-node13: β = 0.028, P = 0.02) for wine consumption and connectivity between the ventral attention network (VAN) and the frontal parietal/caudate nucleus (FP/CN) (node27-node9: β = -0.31, P = 0.04) for total alcohol intake in the past-week and maximum number of drinks per day in the past-year. The predictive models demonstrated strong accuracy, with root mean square error (RMSE) values of 5.15 for odor-related models and 5.14 for taste-related models. The F1 scores were 0.74 for the odor model and 0.71 for the taste model, indicating reliable performance. These findings suggest that specific patterns of brain connectivity associated with taste and olfactory perception may serve as predictors of alcohol consumption behaviors in young adults. Our study highlight the need for longitudinal research to evaluate the potential of taste- and smell-related brain connectivity patterns for early screening and targeted interventions, as well as their role in personalized treatment strategies for individuals at risk of AUD.

PMID:39962224 | DOI:10.1038/s41386-025-02058-7

Sci Data. 2025 Feb 17;12(1):284. doi: 10.1038/s41597-025-04569-w.

ABSTRACT

Neuroimaging has greatly improved our understanding of phobic mechanisms. To expand on these advancements, we present data on the heterogeneity of neural patterns in spider phobia combined with various psychological dimensions of spider phobia, using spider-relevant stimuli of various intensities. Specifically, we have created a database in which 49 spider-fearful individuals viewed 225 spider-relevant images in the fMRI scanner and performed behavioral avoidance tasks before and after the fMRI scan. For each participant, the database consists of the neuroimaging part, which includes an anatomical scan, five passive-viewing, and two resting-state functional runs in both raw and pre-processed form along with associated quality control reports. Additionally, the behavioral section includes self-report questionnaires and avoidance tasks collected in pre- and post-sessions. The dataset is well suited for investigating neural mechanisms of phobias, brain-behavior correlations, and also contributes to the existing phobic neuroimaging datasets with spider-fearful samples.

PMID:39962218 | DOI:10.1038/s41597-025-04569-w

Sci Rep. 2025 Feb 17;15(1):5794. doi: 10.1038/s41598-025-87204-3.

ABSTRACT

Stimulants, such as methylphenidate (MPH), are beneficial for attention-deficit/hyperactivity disorder (ADHD), but individual response varies. A deeper understanding of the mechanisms underpinning response is needed. Previous studies suggest that a single MPH dose modulates resting-state functional connectivity (rs-fc). We investigated whether single-dose induced rs-fc changes were associated with post-dose optimization clinical response. Fifty-six adults with ADHD underwent rs-functional magnetic resonance imaging (rs-fMRI) under placebo and a single MPH dose, before starting MPH treatment. Clinical response was measured at two months. We tested if a single MPH dose (vs. placebo) shifted rs-fc; how these shifts were associated with treatment response (categorical approach); and whether these associations were driven by improvement on either ADHD symptom domain. A single MPH dose (vs. placebo) increased rs-fc in three subcortical-cortical and cerebellar-cortical clusters. Enhanced rs-fc between the cerebellar vermis (lobule 6) and the left precentral gyrus was associated with a greater probability of responding to treatment (χ2(7) = 22.740, p = .002) and with an improvement on both inattentive and hyperactive/impulsive symptoms (both p ≤ .001). We provide proof-of-concept that the brain functional response to a single MPH dose, administered before starting routine treatment, is indicative of two-month clinical response in adult ADHD. This may encourage future replication using clinically applicable measures.

PMID:39962109 | DOI:10.1038/s41598-025-87204-3

Int J Womens Health. 2025 Feb 11;17:369-376. doi: 10.2147/IJWH.S508593. eCollection 2025.

ABSTRACT

INTRODUCTION: Endometriosis is a chronic gynecological disorder that significantly impacts women of reproductive age. Recent evidence suggests a bidirectional link between endometriosis and brain functional networks, though the causal mechanisms remain unclear. This study aims to explore these relationships using Mendelian Randomization (MR) analysis.

METHODS: Data from 191 resting-state functional MRI (rsfMRI) phenotypes and endometriosis genetic datasets were analyzed using both forward and reverse MR approaches. Genetic Instrument Selection was performed to identify valid instrumental variables, ensuring their independence from confounders and strong association with the exposure. Sensitivity analyses were conducted to ensure the robustness of the findings.

RESULTS: Forward MR analysis identified three brain networks (Pheno20, Pheno38, Pheno44) significantly associated with endometriosis risk (P FDR < 0.05). Notably, Pheno38 activity was inversely associated with fallopian tube endometriosis, whereas Pheno20 and Pheno44 were positively linked to adenomyosis. Reverse MR analysis revealed that endometriosis of the ovary was inversely associated with functional connectivity in Pheno932, a network involved in cognitive and attention processes. Sensitivity analyses confirmed the reliability of these results.

DISCUSSION: This study highlights a complex bidirectional relationship between brain functional networks and endometriosis. Increased activity in specific networks may protect against or predispose individuals to certain subtypes of endometriosis. Conversely, endometriosis also can influence brain connectivity, potentially contributing to cognitive and emotional symptoms.

PMID:39959755 | PMC:PMC11829589 | DOI:10.2147/IJWH.S508593

Psychol Med. 2025 Feb 17;55:e49. doi: 10.1017/S0033291725000054.

ABSTRACT

BACKGROUND: The COVID-19 pandemic has had a significant impact on the health of millions of people worldwide, and many manifest new or persistent symptoms long after the initial onset of the infection. One of the leading symptoms of long-COVID is cognitive impairment, which includes memory loss, lack of concentration, and brain fog. Understanding the nature and underlying mechanisms of cognitive impairment in long-COVID is important for developing preventive and therapeutic interventions.

METHODS: Our present study investigated functional connectivity (FC) changes in patients with long-COVID and their associations with cognitive impairment. Resting-state functional MRI data from 60 long-COVID patients and 52 age- and sex-matched healthy controls were analyzed using seed-based functional connectivity analysis.

RESULTS: We found increased FC between the right caudate nucleus and both the left and right precentral gyri in long-COVID patients compared with healthy controls. In addition, elevated FC was observed between the right anterior globus pallidus and posterior cingulate cortex as well as the right temporal pole in long-COVID patients. Importantly, the magnitude of FC between the caudate and the left precentral gyrus showed a significant negative correlation with Montreal Cognitive Assessment (MoCA) scores and a negative correlation with Trail Making Test B performance in the patient group.

CONCLUSION: Patients with long-COVID present enhanced FC between the caudate and the left precentral gyrus. Furthermore, those FC alterations are related to the severity of cognitive impairment, particularly in the domain of executive functions.

PMID:39957507 | DOI:10.1017/S0033291725000054

J Sleep Res. 2025 Feb 17:e70015. doi: 10.1111/jsr.70015. Online ahead of print.

ABSTRACT

To investigate the effective connectivity between the bilateral insulae and other regions of the whole brain in children with obstructive sleep apnea (OSA), and to reveal the relationships between these abnormal connections and cognitive dysfunction in this condition. Resting-state functional magnetic resonance imaging (rs-fMRI) data and clinical variables were collected from 55 children with OSA [5.0 (5.0, 8.0) years, 32 males, 28 pre-school children] and 25 healthy controls [6.0 (5.0, 9.0) years, 11 males, 9 pre-school children], matched for age, gender, and education. Rs-fMRI data were analysed to investigative group-difference in the effective connectivity between the bilateral insulae and other regions of the brain of children with OSA with those of controls. Spearman correlation analysis was conducted between these abnormal connections and clinical variables among children with OSA. Compared with controls, children with OSA showed abnormal clinical variables (i.e., increased OAHI, AHI, OAI, HI, ODI, time of SpO2 < 90%, total AI, and respiratory-related AI, while decreased minimal SpO2, FIQ, VIQ, and PIQ). Additionally, significant alterations were observed in the effective connectivity between the bilateral insulae and other regions of brain, such as frontal, parietal, occipital, and cerebellum and so forth. Furthermore, the mean values of the effective connectivity in children with OSA were significantly correlated with several sleep-related and neurocognitive parameters. There exist abnormal causal interactions between the bilateral insulae and other regions throughout the brain in OSA children, accompanied by impaired cognitive function, suggesting that the former may be a potential neural mechanism underlying the latter.

PMID:39957378 | DOI:10.1111/jsr.70015

Brain Res Bull. 2025 Feb 14:111259. doi: 10.1016/j.brainresbull.2025.111259. Online ahead of print.

ABSTRACT

Sensory impairment after stroke has become an important health problem that affects the health and quality of life of patients. Acupuncture is a widely accepted method for stroke rehabilitation. The development of fMRI provides a good platform for the study of neural activity patterns induced by acupuncture, and many studies have found that acupuncture can induce special activation of the brain in stroke patients. We introduced the inter-subject functional connectivity(ISFC) method into the study of acupuncture treatment for sensory impairment after stroke to explore the group effects of acupuncture treatment and the specific mode of action of acupuncture for sensory impairment. In this study, 24 stroke patients with limb numbness and 23 healthy controls were included, and three functional magnetic resonance scans were designed, including resting state, acupuncture task state, and acupuncture-retention state(LI11 and ST36 were used during the task fMRI). The main observation was the connection changes in 50 regions of interest, including the sensory-motor network, central executive network, thalamus, cingulate gyrus, and other brain regions. The findings showed that acupuncture could cause certain patterns of neural activity in the patients. These patterns included a significant rise in ISFC within the sensory-motor network and between the sensory-motor network and the thalamus and the central executive network. When different types of acupuncture were compared, it was found that the first effect of acupuncture was mostly large-scale activation of the sensory-motor network and the thalamus. The second effect, on the other hand, was low-intensity activation in a limited range. In general, this study explored the group mechanism of acupuncture for sensory function rehabilitation after stroke and provided some help for understanding neural activity patterns from a cross-subject dimension.

PMID:39956399 | DOI:10.1016/j.brainresbull.2025.111259

Brain Lang. 2025 Feb 15;264:105551. doi: 10.1016/j.bandl.2025.105551. Online ahead of print.

ABSTRACT

Associative theories of creativity posit that high-creativity individuals possess flexible semantic memory structures that allow broad access to varied information. However, the semantic memory structure characteristics and neural substrates of creative writing are unclear. Here, we explored the semantic network features and the predictive whole-brain functional connectivity associated with creative writing and generated mediation models. Participants completed two creative story continuation tasks. We found that keywords from written texts with superior creative writing performance encompassed more semantic categories and were highly interconnected and transferred efficiently. Connectome predictive modeling (CPM) was conducted with resting-state functional magnetic resonance imaging (fMRI) data to identify whole-brain functional connectivity patterns related to creative writing, dominated by default mode network (DMN). Semantic network features were found to mediate the relationship between brain functional connectivity and creative writing performance. These results highlight how semantic memory structure and the DMN-driven brain functional connectivity patterns support creative writing performance. Our findings extend prior research on the role of semantic memory structure and the DMN in creativity, expand upon previous research on semantic creativity, and provide insight into the cognitive and neural foundations of creative writing.

PMID:39955819 | DOI:10.1016/j.bandl.2025.105551

Mol Psychiatry. 2025 Feb 15. doi: 10.1038/s41380-025-02924-2. Online ahead of print.

ABSTRACT

Deficits in mediodorsal thalamus-dorsolateral prefrontal cortex (MDT-DLPFC) resting-state functional magnetic resonance imaging (rs-fMRI) connectivity and prefrontal sleep spindles have been reported in chronic and early course schizophrenia. However, the presence of these alterations in clinical high-risk for psychosis (CHR), alongside their relationships with underlying neurotransmission and cognitive function, remains to be established. Thirty-one CHR and thirty-two HC underwent: 1) 7 T rs-fMRI; 2) 7 T magnetic resonance spectroscopy imaging (MRSI); and 3) sleep electroencephalography (EEG). Rs-fMRI connectivity was analyzed by seeding the whole thalamus (WT) and seven thalamic subsections. Spindle duration was computed across all EEG channels. GABA/creatine (Cr) and glutamate/Cr were calculated in DLPFC and MDT. Relative to HC, CHR showed WT-DLPFC hypoconnectivity (p-FDR = 0.001), especially involving MDT-DLPFC (p-FDR < 0.001) and reduced prefrontal spindle duration (t-stat = -2.64, p = 0.010), while no differences were found for MRSI neuro-metabolites. We then performed clustering analysis using rs-fMRI connectivity and spindle duration to identify CHR and HC subgroups and predict their working memory (WM) performance. A cluster with intact rs-fMRI and spindle duration included mostly HC (83.33% purity), while a cluster with both measures altered involved almost entirely CHR (91.66% purity) and showed worse WM performances. We also examined MRSI metabolites' contribution to spindles and rs-fMRI connectivity with a within-group multivariable regression analysis. In HC, but not in CHR, MDT glutamate/Cr negatively predicted spindle duration and positively predicted MDT-DLPFC connectivity. Combined, these findings indicate that a multimodal neuroimaging approach can identify distinct thalamocortical dysfunctions in CHR individuals, thus informing future research aimed at developing personalized interventions in these individuals.

PMID:39955469 | DOI:10.1038/s41380-025-02924-2

J Neurol Sci. 2025 Jan 21;470:123399. doi: 10.1016/j.jns.2025.123399. Online ahead of print.

ABSTRACT

BACKGROUND: Post-stroke fatigue (PSF) is one of the most prevalent symptoms that affects quality of life and daily function after stroke. Despite a growing body of research, its pathophysiology is poorly understood. Non-invasive brain stimulation (NIBS), such as the transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), can serve as a non-pharmacological intervention for PSF. In this review, we aim to (1) evaluate PSF neuroimaging studies to deduce potential neural mechanisms, (2) describe NIBS as a tool to probe brain structures to further understand pathophysiology of fatigue, and (3) assess NIBS as a treatment intervention for PSF.

METHODS: A systematic search was conducted for the databases PubMed, Embase, Scopus, CINAHL and Cochrane. Studies were included based on the following inclusion and exclusion criteria: >18 years with PSF, use of neuroimaging and/or NIBS for investigation or as an intervention for PSF, English language, study types including cohort, case control, or randomized controlled trials. Data extracted included participant characteristics, concept, context, study methods, and key findings relevant to the review questions.

RESULTS: A total of 30 studies met criteria. Neuroimaging papers that investigated brain structure (MRI) found conflicting associations between lesion location and PSF. Functional methods (fMRI, TMS) revealed altered resting state functional connectivity (rsFC), cortical excitability, and a disruption in interhemispheric inhibitory balance as potential mechanisms of PSF. There were no studies using TMS as an intervention for PSF. Of the six articles that used tDCS, only two reported statistically significant reductions in the severity of PSF.

CONCLUSION: Structural characteristics of stroke lesions had conflicting findings, while functional neuroimaging studies suggested that altered rsFC, cortical excitability and interhemispheric inhibitory balance contribute to the development of PSF. There were inconsistent results on the effectiveness of tDCS as an intervention for PSF, due to varying methodologies and lack of precise targeting of underlying neural mechanisms. Further investigations are needed to determine if NIBS could be a potential treatment to alleviate the effects of PSF.

PMID:39954574 | DOI:10.1016/j.jns.2025.123399

Sleep Med. 2025 Feb 6;128:174-182. doi: 10.1016/j.sleep.2025.02.009. Online ahead of print.

ABSTRACT

OBJECTIVES: Obstructive sleep apnea (OSA) is associated with potential disruptions in brain function and structure. The aim was to investigate alterations in dynamic functional connectivity (dFC) in OSA patients utilizing resting-state functional magnetic resonance imaging (rs-fMRI) and multiplication of temporal derivatives (MTD) to better understand the neurological implications of OSA.

METHODS: This cross-sectional study eventually recruited 111 patients, aged 25-65 years. We categorized participants based on the apnea-hypopnea index (AHI) assessed via polysomnography (PSG), 43 patients were groupAHI <15 and 68 patients were group AHI ≥15. Rs-fMRI and neuropsychological assessments were conducted to assess the brain function and visual-spatial memory, respectively. We evaluated the intergroup differences in dFC as well as its correlation with clinical parameters.

RESULTS: The dFC analysis identified five distinct connectivity states, comprising four hyperconnected states (State 1, 2, 3, and 5) and one hypoconnected state (State 4). Group AHI≥ 15 showed altered fraction time (FT) and mean dwell time (MDT) in States 1, 3, and 4. The partial correlation showed that the FT/MDT of State 1 negatively correlated with hypoxia parameters, while the FT/MDT of State 3 positively correlated with total sleep time in Group AHI≥ 15. Group AHI≥ 15 exhibited a negative association between FT of state 3 and Visuospatial/Executive score in MoCA (r = -0.297, p = 0.033).

CONCLUSIONS: Untreated male moderate to severe OSA patients exhibited altered in dFC, which significantly correlated with hypoxia parameters and cognitive performance, high lighting that dFC changes may be an indicator of the neurological consequence of OSA, especially moderate to severe OSA.

PMID:39954375 | DOI:10.1016/j.sleep.2025.02.009

Brain Behav Immun. 2025 Feb 12:S0889-1591(25)00026-1. doi: 10.1016/j.bbi.2025.01.013. Online ahead of print.

ABSTRACT

Currently, our understanding of the metabolic and immune pathways involved in obsessive-compulsive disorder (OCD), as well as the precise mechanisms by which metabolism and immunity impact brain activity and function, is limited. This study aimed to examine the alterations in serum metabolites, inflammatory markers, brain activity, and brain functional connectivity (FC) among individuals with OCD and investigate the relationship between these factors. The study included 55 individuals with moderate-to-severe OCD (either drug-naïve or not taking medication for at least eight weeks) and 54 healthy controls (HCs). The High-Performance Liquid Chromatography-Tandem Mass Spectrometry (HPLC-MS/MS) technique was used to detect serum metabolites, whereas the enzyme-linked immunosorbent assay (ELISA) was utilized to identify inflammatory markers. The FC of the brain was investigated using rs-fMRI. The findings demonstrated that individuals with OCD exhibited significant alterations in 11 metabolites compared to HCs. In particular, 10 of these metabolites exhibited an increase, while one metabolite displayed a decrease. Additionally, individuals with OCD experienced a marked elevation in the levels of five inflammatory factors (TNF-α, IL-1β, IL-2, IL-6, and IL-12). Rs-fMRI analysis revealed that individuals with OCD exhibited atypical FC in various brain regions, such as the postcentral gyrus, angular gyrus, and middle temporal gyrus. These specific brain areas are closely associated with sensory-motor processing, cognitive control, and emotion regulation. Further stepwise multiple regression analysis revealed that serum metabolite levels, particularly phosphatidylcholine, and inflammatory markers such as IL-1β could predict alterations in brain FC among individuals diagnosed with OCD. In summary, this study uncovered that individuals with OCD exhibit alterations in serum metabolites, inflammatory markers, brain activity, and FC. The findings suggest that these metabolites and inflammatory markers might play a role in the development and progression of OCD by affecting brain activity and the FC of neural networks.

PMID:39952302 | DOI:10.1016/j.bbi.2025.01.013

Sci Rep. 2025 Feb 14;15(1):5524. doi: 10.1038/s41598-025-86762-w.

ABSTRACT

How does the brain support 'wellbeing'? Because it is a multidimensional construct, it is likely the product of multiple co-active brain networks that vary across individuals. This is perhaps why prior neuroimaging studies have found inconsistent anatomical associations with wellbeing. Furthermore, these used 'laboratory-style' or 'resting-state' methods not amenable to finding manifold networks. To address these issues, we had participants watch a full-length romantic comedy-drama film during functional magnetic resonance imaging. We hypothesised that individual differences in wellbeing measured before scanning would be correlated with individual differences in brain networks associated with 'embodied' and 'narrative' self-related processing. Indeed, searchlight spatial inter-participant representational similarity and subsequent analyses revealed seven sets of co-activated networks associated with individual differences in wellbeing. Two were 'embodied self' related, including brain regions associated with autonomic and affective processing. Three sets were 'narrative self' related, involving speech, language, and autobiographical memory-related regions. Finally, two sets of visual-attention-related networks emerged. These results suggest that the neurobiology of wellbeing in the real world is supported by diverse but functionally definable and separable sets of networks. This has implications for psychotherapy where individualised interventions might target, e.g., neuroplasticity in language-related narrative over embodied self or visual-attentional related processes.

PMID:39952989 | DOI:10.1038/s41598-025-86762-w