Most recent paper

Front Oncol. 2026 May 29;16:1850713. doi: 10.3389/fonc.2026.1850713. eCollection 2026.

ABSTRACT

BACKGROUND: Modern linguistic theories propose that language processing is supported by widely distributed large-scale modules that flexibly interact with domain-general networks. Progressive gliomas tend to reshape the language-associated systems causing dynamic reorganization that can be characterized by resting-state and task-based fMRI, thereby informing surgical decision-making. However, the interplay of neuropathological factors influencing reorganization patterns remains unclear, with ambiguity regarding the recruitment of cognitive resources across various levels of linguistic complexity.

METHODS: We included 100 patients with gliomas and 127 matched normal controls in this study. Activation analyses were performed on task fMRI data acquired during a picture-naming paradigm. Spectral DCM and connectome analyses were combined to examine state-dependent shifts between rest and task conditions. ANOVAs were used to assess relationships between clinicopathological factors and compensatory mechanisms. Mediation analyses were used to explore the mediated pathways among clinicopathological factors, topological indicators, and language performance.

RESULTS: First, we observed widely distributed activations associated with glioma-induced perilesional and remote reorganization patterns, exhibiting predominantly right-hemispheric lateralization in domain-general networks. VLSM analyses further showed that the spatial distribution of these activation clusters was significantly associated with tumor location and grade. Second, spectral DCM analyses indicated that task demands were associated with a greater number of positive effective connections across the reorganized language network, interactions among which were inherently dynamic varying with exogenous linguistic complexity and endogenous functional integrity. Third, ANOVAs suggested that alterations in language network topology were accompanied by flexible engagement of domain-general network components, which were associated with a partial restoration of the balance between integration and segregation under task conditions. Finally, we identified associations and potential mediation pathways among clinicopathological factors, topological properties, and language performance, consistent with the concept of glioma-related network metaplasticity.

CONCLUSION: Our findings highlight that the dynamics of language reorganization depend on clinicopathological factors of gliomas and may thus open new perspectives for personalized surgical strategies for functional protection in the era of network neurosurgery. These group-level findings provide a modeling framework that may guide future research toward individualized network assessment and surgical planning.

PMID:42294334 | PMC:PMC13259869 | DOI:10.3389/fonc.2026.1850713

Front Hum Neurosci. 2026 May 29;20:1859875. doi: 10.3389/fnhum.2026.1859875. eCollection 2026.

ABSTRACT

OBJECTIVE: Non-pharmacological somatic interventions can modulate brain function via body-brain communication, yet the underlying neurobiological mechanisms remain unclear. This study used resting-state fMRI and JuSpace spatial correlation to investigate how meridian-sinew therapy affects regional brain function and its spatial coupling with neurotransmitter systems in healthy volunteers.

METHODS: Forty-two healthy volunteers underwent resting-state fMRI and a 2-back working memory task before and after a 50 min meridian-sinew therapy session. We quantified changes in local brain activity using ALFF and ReHo. JuSpace was applied to examine spatial correlations between functional alteration maps and neurotransmitter receptor/transporter density atlases.

RESULTS: Post-intervention reaction time in the 2-back task was significantly reduced. Neuroimaging revealed increased ALFF and ReHo in the prefrontal cortex, and decreased ReHo in the left putamen and insula. Spatial correlation analyses showed that ALFF changes were significantly correlated with 5-HT2a, CB1, mGluR5, DAT, NAT, NMDA, SERT, and VAChT distributions, while ReHo changes correlated only with SERT.

CONCLUSION: Meridian-sinew therapy modulates regional brain physiology by enhancing prefrontal neural activity and suppressing subcortical interoceptive processing, accompanied by improved working memory efficiency. These functional changes show consistent spatial associations with multiple neurotransmitter systems. Our findings provide multimodal neuroimaging evidence for understanding how somatic interventions shape brain function through body-brain communication pathways.

PMID:42294096 | PMC:PMC13260330 | DOI:10.3389/fnhum.2026.1859875

Depress Anxiety. 2026 Jun 11;2026:4701907. doi: 10.1155/da/4701907. eCollection 2026.

ABSTRACT

BACKGROUND: This study aimed to investigate the neural basis of individual differences in antidepressant efficacy using an 8-week longitudinal multitime point resting-state functional magnetic resonance imaging (fMRI) design.

METHODS: Forty-eight patients with major depressive disorder (MDD) completed two or three scans, and 44 healthy controls (HCs) underwent a baseline scan. Patients were categorized into remission (MDDr) and nonremission (MDDnr) groups based on treatment outcomes. Group differences in resting-state functional connectivity (rsFC) of the amygdala subregions at baseline were examined among MDDr, MDDnr, and HCs. Longitudinal changes in the identified rsFC were compared between the MDDr and MDDnr groups. Correlation analyses were conducted to explore the relationship between baseline rsFC or its longitudinal changes and depressive symptom severity or improvement.

RESULTS: At baseline, rsFC between the right basolateral (BL) amygdala and the right supplementary motor area (SMA) was lower in the MDDr group but higher in the MDDnr group compared with HCs, although this effect did not survive multiple comparisons correction across amygdala subregions. The trajectory of this rsFC differed between the two patient groups during treatment, with normalization observed at 2 and 8 weeks posttreatment. Correlation analyses indicated that baseline rsFC was associated with treatment response and that longitudinal changes in rsFC were aligned with symptom improvement, although some associations did not survive multiple comparisons correction.

CONCLUSIONS: Our findings provide novel and valuable insights into the neural mechanisms underlying antidepressant response and highlight the role of amygdala subregional connectivity in explaining interindividual variability in treatment efficacy.

TRIAL REGISTRATION: ClinicalTrials.gov identifier: ChiCTR2400093823.

PMID:42292915 | PMC:PMC13254815 | DOI:10.1155/da/4701907

J Biomed Phys Eng. 2026 Jun 1;16(3):205-218. doi: 10.31661/jbpe.v0i0.2505-1930. eCollection 2026 Jun.

ABSTRACT

BACKGROUND: Functional Magnetic Resonance Imaging (fMRI) is a powerful modality for investigating changes in healthy brains and those with disorders. Anosmia, an olfactory disorder, is commonly associated with traumatic brain injury, particularly in patients suffering from severe trauma.

OBJECTIVE: In this study, we aimed to utilize Resting-State fMRI (rs-fMRI) to examine changes in Functional Connectivity (FC) networks between Healthy Controls (HCs) and patients with Post-Traumatic Anosmia (PTA).

MATERIAL AND METHODS: In this retrospective study, we performed rs-fMRI on forty-four PTA patients and forty-three HCs. The Sniffin' Sticks test was used to assess olfactory function. Seed-based Analysis (SBA) and Independent Component Analysis (ICA) were conducted using MATLAB-based imaging software.

RESULTS: PTA patients showed lower Threshold-Discrimination-Identification (TDI) scores compared to HCs. SBA revealed increased FC correlations in the anterior cingulate cortex, piriform, insular cortex, and prefrontal area in PTA patients. Using ICA on the whole brain network, we found increased FC in the right frontal pole, cerebellum, right putamen, anterior cingulate cortex, postcentral gyrus, orbitofrontal cortex, and amygdala in PTA compared to HCs. In PTA patients, global efficiency of the entire brain network showed a significant association with olfactory performance.

CONCLUSION: This study suggests that neural-level olfactory deficits following head trauma are most accurately characterized through SBA and ICA analyses in higher-order regions outside the primary olfactory cortex.

PMID:42292679 | PMC:PMC13263385 | DOI:10.31661/jbpe.v0i0.2505-1930

Front Neurosci. 2026 May 29;20:1803897. doi: 10.3389/fnins.2026.1803897. eCollection 2026.

ABSTRACT

INTRODUCTION: Neural network effects of transcranial direct current stimulation (tDCS) are poorly understood. Here, we introduce a prospective, empirically informed, multimodal functional magnetic resonance imaging (fMRI) framework for guiding target selection and hypothesis-based analysis in future focal tDCS-fMRI studies.

METHODS: We illustrate our approach by using data of 37 healthy individuals (19 females; mean age ± SD = 25.8 ± 5.9) recruited from two tDCS-fMRI studies that were acquired at the same scanner and with placebo-tDCS. Participants completed two resting-state (RS) sessions and two task-fMRI sessions (object-location memory, OLM, or associative picture-pseudoword learning, APPL, experiments). Seed-based RS analysis identified functional networks originating from target regions for focal tDCS (right occipito-temporal cortex, rOTC; left ventral IFG, lvIFG) and established their test-retest reliability (TRR), using intraclass correlation coefficients (ICC). Dice coefficients quantified overlap between seeded RS networks and task-evoked activity to identify task-active regions potentially affected by downstream network effects from the target regions.

RESULTS: Seed-based analyses identified highly reliable ventral visual-limbic (rOTC) and language-related networks (lvIFG), with 72-77% of voxels showing good-to-excellent TRR (ICC ≥ 0.75). Only a subset of network voxels identified by the RS analyses overlapped with activity elicited by the experimental paradigms (ranging from 7.5-55%), with larger correspondence for the OLM (Dice: 0.249-0.349; APPL 0.065-0.106). Therefore, the degree of potential tDCS network effects varied substantially depending on the target region, the extent of its functional network and task-specific activity patterns. Degree of correspondence was further mediated by the selected contrasts-of-interest in the task-based analyses, with more conservative control conditions resulting in reduced overlap.

CONCLUSION: In sum, we established a principled multimodal fMRI framework bridging a critical gap in neuromodulation research. By integrating reliable intrinsic connectivity maps with task-evoked activity patterns, we provide a method to prospectively identify network-level targets for focal brain stimulation and generate hypotheses for tDCS-fMRI analyses. This approach shifts the rationale from stimulating isolated brain regions to strategically targeting key nodes within a predefined functional pathway.

PMID:42292341 | PMC:PMC13260067 | DOI:10.3389/fnins.2026.1803897

Transl Psychiatry. 2026 Jun 15. doi: 10.1038/s41398-026-04142-y. Online ahead of print.

ABSTRACT

Anxiety is highly comorbid with disorders of gut-brain interaction, including irritable bowel syndrome (IBS). The gut microbiota is implicated in both conditions, yet the underlying mechanisms remain unclear. This study aimed to elucidate the neuropathological basis of anxiety in diarrhea-predominant IBS (IBS-D) and identify potential microbiota-based therapeutic targets. Here, Mendelian randomization analysis established a bidirectional causal relationship between IBS and anxiety. In our clinical cohort, 35.85% of IBS-D patients presented with comorbid anxiety, and GAD-7 anxiety scores correlated significantly with IBS symptom severity. Resting-state functional magnetic resonance imaging (rs-fMRI) revealed that IBS-D patients with comorbid anxiety exhibited significantly altered regional homogeneity (ReHo) in nine brain regions, with the most pronounced reductions observed in the bilateral amygdala. Moreover, bilateral amygdala ReHo could effectively differentiate these patients, with receiver operating characteristic (ROC) analysis yielding area under curve (AUC) of 0.746. To investigate the underlying pathology, we established a water avoidance stress (WAS) mouse model that successfully recapitulated the anxiety-like behaviors and visceral hypersensitivity observed clinically. Critically, these phenotypes were transmissible, as recipient mice colonized with microbiota from the WAS-induced IBS-D group also developed visceral hypersensitivity and anxiety-like behaviors. Phocaeicola vulgatus was determined as a key bacterial strain significantly depleted in both our IBS-D patient cohort and the WAS-induced IBS-D mice, with its abundance negatively correlating with anxiety levels. As anticipated, IBS-D patients with lower abundance of P. vulgatus exhibited reduced amygdala ReHo and Mendelian randomization analysis identified P. vulgatus as a protective factor against anxiety. Correspondingly, therapeutic supplementation with P. vulgatus ameliorated anxiety-like behaviors in WAS-induced IBS-D mice by attenuating neuroinflammation and restoring neuronal morphology in the amygdala. In conclusion, this study provides the first evidence that P. vulgatus can alleviate anxiety in IBS by targeting amygdala-centered neuropathology, presenting a novel psychobiotic strategy for treating emotional comorbidities in disorders of gut-brain interaction.

PMID:42289401 | DOI:10.1038/s41398-026-04142-y

Addict Behav. 2026 Jun 11;182:108775. doi: 10.1016/j.addbeh.2026.108775. Online ahead of print.

ABSTRACT

BACKGROUND: Tobacco use disorder (TUD) is a major public health issue with significant individual differences. A deeper understanding of its neurobiology and reliable biomarkers is needed. This study investigated whether inter-subject variability in resting-state brain functional connectivity (IVFC) could serve as such a marker for TUD.

METHODS: Resting-state fMRI data from 123 male TUD patients and 123 healthy controls (HCs) were collected and analyzed. IVFC was computed within seven major brain lobes. Five machine learning models (random forest, gradient boosting, extra trees, multi-layer perceptron, and support vector machine) were trained to classify the groups based on IVFC features. Univariate regression was conducted with each lobe's IVFC predicting clinical scores. Multivariate stepwise regression was then performed to identify the best combination of IVFC predictors for dependence severity.

RESULTS: TUD showed significantly altered IVFC in six brain lobes compared to controls, with the largest difference in the insular lobe. The machine learning models, particularly the extra trees classifier, achieved high accuracy (up to 88 %) in classifying TUD, primarily utilizing features from the temporal and limbic lobes. Univariate regression showed that higher IVFC in frontal, insular, limbic, and temporal lobes was associated with lower nicotine dependence severity. Multivariate stepwise regression identified insular lobe IVFC as the sole independent predictor.

CONCLUSIONS: These findings suggest that widespread alterations in IVFC may characterize TUD and relate to its clinical severity, indicating the potential value of this measure as a neurobiological marker. The combination of IVFC analysis with machine learning appears to offer a promising approach for distinguishing TUD, which could contribute to advancing our understanding of its underlying brain mechanisms.

PMID:42289141 | DOI:10.1016/j.addbeh.2026.108775

BMC Med Imaging. 2026 Jun 13. doi: 10.1186/s12880-026-02503-z. Online ahead of print.

ABSTRACT

BACKGROUND: Cerebrovascular reactivity(CVR), a key indicator of cerebrovascular reserve, is crucial for evaluating cerebrovascular pathophysiology. This study employed resting-state MRI (rs-MRI) to assess CVR alteration in patients with unilateral middle cerebral artery stenosis or occlusion (MCA-S) under non-hypercapnic conditions, comparing them with healthy controls.

METHODS: A total of 41 patients with unilateral MCA-S and 50 age-, sex-, and education-matched normal controls (NC). All underwent rs-MRI and neuropsychological assessments. CVR was derived from rs-fMRI frequency band signals, and t-test was conducted to obtain the CVR-differentiated brain regions. Exploratory seed-based FC analysis was further performed to characterize the network context of regions showing altered CVR. Partial correlation analyses explored relationships between these differential brain regions and both neuropsychological assessments and clinical indicators. Discriminative performance of the CVR-related metric between MCA-S and controls was evaluated using receiver operating characteristic (ROC) curves.

RESULTS: Compared with the NC group, patients with MCA-S exhibited increased CVR in the contralesional Cerebellum Crus1 (CC1) and decreased iCVR in the ipsilesional postcentral gyrus (PoCG). When contralesional CC1 served as regions of interest (ROIs), increased FC was observed in the ipsilesional middle frontal gyrus (MFG) and the contralesional precuneus of MCA-S patients. The partial correlation analysis indicated a positive correlation between the FC of the ipsilesional MFG and anxiety scores (r = 0.404, (95%CI: 0.106, 0.631), P = 0.012, P-FDR = 0.030). Using ipsilesional PoCG as the ROI, MCA-S patients showed significantly decreased FC in ipsilesional PoCG, contralesional precentral gyrus (PreCG), and ipsilesional supplementary motor area. The FC of the contralesional PreCG showed a positive correlation with anxiety scores (r = 0.436, (95%CI: 0.142, 0.658), P = 0.006, P-FDR = 0.030). ROC analysis demonstrated strong diagnostic accuracy for CVR in CC1 (AUC = 0.809) and PoCG (AUC = 0.787), with a combined AUC of 0.866.

CONCLUSION: Non-hypercapnic rs-MRI effectively evaluates CVR alterations in MCA-S patients and may serve as a complementary physiological biomarker for characterizing hemodynamic alteration.

PMID:42288826 | DOI:10.1186/s12880-026-02503-z

Brain Res Bull. 2026 Jun 13:112008. doi: 10.1016/j.brainresbull.2026.112008. Online ahead of print.

ABSTRACT

OBJECTIVE: This study uses resting-state functional magnetic resonance imaging (fMRI) to understand and compare the effects of hypoxic conditions at high and ultra-high altitudes.

METHODS: Regional homogeneity (ReHo) and degree centrality (DC) values were calculated and compared between 47 low-altitude (LA, <500m), 39 high-altitude (HA, 1520m), and 34 ultra-high-altitude (UHA, 3650m) healthy adults. Correlations with heart rate and blood oxygen saturation (SpO₂) were analyzed.

RESULTS: Compared to the LA group, the UHA/HA group had significantly lower ReHo values in the bilateral basal ganglia, prefrontal lobes (left/right), left paracentral lobule, and these were positively correlated with SpO₂. Conversely, ReHo values were significantly higher in the bilateral posterior occipital and left superior parietal lobes, and were negatively correlated with SpO₂. DC values were significantly lower in the left orbitofrontal cortex, bilateral pallidum and left inferior frontal gyrus, and were positively correlated with SpO₂. Synchronous decreases in ReHo and DC were found in the left prefrontal cortex, bilateral pallidum and putamen.

CONCLUSION: In high-altitude environments, functional activity is decreased in the basal ganglia, prefrontal cortex, and hippocampus, is accompanied by a compensatory increase in the occipital and superior parietal lobes. Concurrent reductions in DC and ReHo within the left prefrontal cortex, bilateral pallidum and putamen might serve as biomarkers for high-altitude hypoxic functional alterations and aid early detection and intervention of hypoxia-induced brain damage.

PMID:42288178 | DOI:10.1016/j.brainresbull.2026.112008

Brain Inform. 2026 Jun 13. doi: 10.1186/s40708-026-00312-2. Online ahead of print.

ABSTRACT

Deficits in neural information integration are hypothesized to underlie diverse psychiatric symptoms, yet the specific patterns of alteration across different disorders remain unclear. In this study, we decomposed information dynamics between brain regions into synergistic and redundant components using a recent information-theoretic approach based on Partial Information Decomposition and applied to resting-state fMRI data from individuals with schizophrenia (SZ), autism spectrum disorder (ASD), and attention-deficit/hyperactivity disorder (ADHD). Our analysis revealed distinct disorder-specific profiles: SZ and ASD exhibited a widespread reduction in synergy, whereas ADHD showed a contrasting increase. Furthermore, ASD was uniquely characterized by a significant reduction in redundancy. Meta-analytic functional annotation using NeuroSynth associated synergy with higher-order cognitive functions and redundancy with lower-level sensorimotor processing. To investigate multivariate organization of these patterns that distinguish psychiatric diagnoses, we employed Linear Discriminant Analysis (LDA). This analysis demonstrated that synergy and redundancy partially capture distinct dimensions of network variation, exhibiting substantial complementarity in their multivariate structure. While redundancy overlapped considerably with correlation-based connectivity, synergy reflected additional structure not fully represented by conventional measures. Together, these findings indicate that decomposing information dynamics provides complementary perspectives on large-scale network organization, offering a refined framework for characterizing psychiatric and neurodevelopmental disorders.

PMID:42287597 | DOI:10.1186/s40708-026-00312-2

Brain Connect. 2026 Jun 13:21580014261456366. doi: 10.1177/21580014261456366. Online ahead of print.

ABSTRACT

BACKGROUND: Investigation of the neural substrates of post-traumatic stress disorder (PTSD) in military personnel using whole-brain approaches remains scarce, hindering the development of circuit-based neuromodulatory interventions.

OBJECTIVES: This study aimed to identify potential associations between clinical symptoms and whole-brain resting-state functional connectivity with magnetic resonance imaging in military personnel with adulthood-onset war-related PTSD.

METHODS: Thirty-seven soldiers from the Canadian Armed Forces with moderate to severe treatment-resistant PTSD participated in this study. We assessed PTSD, anxiety and depressive symptoms, quality of life, and time since trauma. We characterized the whole-brain functional connectome using independent component analysis and regions of interest (ROI)-to-ROI connectivity, as well as its topology using graph theory.

RESULTS: Greater severity of PTSD and anxiety symptoms was associated with lower connectivity (r < 0) between the default mode network (DMN) and frontoparietal network. Greater severity of PTSD symptoms was also associated with a higher nodal clustering coefficient of the inferior parietal lobule from the DMN. Greater severity of anxiety symptoms and longer time since trauma was the only clinical variables that correlated with higher connectivity patterns, all involving the visual networks (the frontoparietal-visual, the visual-DMN, and within-visual networks).

CONCLUSIONS: This work contributes to identifying brain targets for the development of personalized neuromodulatory interventions. In particular, the DMN may be a promising target to alleviate PTSD symptoms, and the visual network may be a target to treat comorbid anxiety symptoms.

PMID:42287083 | DOI:10.1177/21580014261456366

J Neuroeng Rehabil. 2026 Jun 12. doi: 10.1186/s12984-026-02048-w. Online ahead of print.

ABSTRACT

BACKGROUND: Motor recovery after ischemic stroke involves complex functional reorganization, yet the underlying molecular and cellular mechanisms remain poorly understood. This study integrated longitudinal neuroimaging and brain-wide transcriptomic data to characterize the functional dynamics and their gene-expression correlates during motor recovery following subcortical ischemic stroke.

METHODS: We recruited 34 patients with acute right subcortical ischemic stroke and 32 age- and sex-matched healthy controls. All participants underwent baseline resting-state functional magnetic resonance imaging, with 22 patients completing a 3-month follow-up scan. Spontaneous neural activity was assessed using the amplitude of low-frequency fluctuations (ALFF), followed by seed-based whole-brain functional connectivity (FC) analysis from regions with longitudinal ALFF differences. We then applied partial least squares (PLS) regression to spatially correlate longitudinal ALFF changes with transcriptomic data from the Allen Human Brain Atlas, identifying a gene expression profile spatially associated with these ALFF changes. These genes were subsequently subjected to functional enrichment and cell-type specificity analyses.

RESULTS: Compared with healthy controls, acute-stage stroke patients showed significantly decreased ALFF in the contralesional precentral gyrus. At 3-month follow-up, ALFF in this region significantly increased, accompanied by strengthened interhemispheric FC with its ipsilesional homologue. Critically, these longitudinal changes in ALFF and interhemispheric FC were significantly correlated with motor recovery. Based on PLS regression, we further identified a specific gene expression profile spatially correlated with the observed ALFF changes. This gene set was specifically enriched in excitatory and inhibitory neurons and was primarily involved in synaptic structure and signaling.

CONCLUSIONS: By linking macroscale imaging dynamics with microscale molecular features, this study demonstrates that the contralesional precentral gyrus plays a supportive role in motor recovery during the subacute phase of subcortical ischemic stroke, with neuronal synaptic plasticity as a potential mechanism. Collectively, these findings inform stage-specific strategies to target interhemispheric inhibition.

PMID:42286663 | DOI:10.1186/s12984-026-02048-w

J Affect Disord. 2026 Jun 12:122127. doi: 10.1016/j.jad.2026.122127. Online ahead of print.

ABSTRACT

BACKGROUND: Hyperactivity-impulsivity (HI) is a core ADHD symptom associated with the monoamine oxidase A (MAOA) gene. The neurobiological mechanisms underlying HI heterogeneity in children carrying the MAOA risk genotype remain unclear and may involve distinct subtypes.

METHODS: A total of 326 children with ADHD were genotyped for MAOA, including 108 non-risk and 218 risk carriers. Semi-supervised clustering of HI and executive function (EF) scores from the ADHD Rating Scale, Conners' Rating Scale, and BRIEF was used to classify MAOA risk carriers into subtypes, with non-risk patients as the reference. fALFF differences across subtypes, cognitive mediation between brain activity and behavior, and treatment response at follow-up were examined.

RESULTS: Two subtypes were identified among MAOA risk carriers. Compared with the non-risk group, Subtype 1 showed elevated HI and impaired EF, whereas Subtype 2 showed preserved EF and no HI elevation. Subtype 1 had increased fALFF in the inferior temporal gyrus and higher putamen fALFF than Subtype 2, while Subtype 2 showed increased fALFF in the angular gyrus relative to the non-risk group. Putamen fALFF was associated with inhibition, shifting, emotional control, and the Behavioral Regulation Index (BRI), and mediation analysis suggested an indirect effect on HI via the BRI. After 4 weeks of medication, Subtype 2 showed greater improvement in conduct problems and anxiety.

CONCLUSION: Putamen function may underlie HI heterogeneity among MAOA risk carriers and was associated with better EF, milder symptoms, and greater treatment response.

PMID:42285531 | DOI:10.1016/j.jad.2026.122127

bioRxiv [Preprint]. 2026 Jun 4:2026.06.01.729443. doi: 10.64898/2026.06.01.729443.

ABSTRACT

Understanding the principles governing large-scale functional organization of the brain remains a central challenge in systems neuroscience. Despite convergent findings, substantial variability across analytical approaches suggests that functional networks may not admit a unique partitioning. Here, we propose that this variability reflects an intrinsic property of the connectome itself: its organization may be fundamentally multi-modal rather than singular.To test this hypothesis, we employ a Bayesian generative modeling framework based on stochastic block models, enabling principled comparison of competing organizational principles and characterization of the full posterior distribution over network partitions. Applying this framework to resting-state fMRI data in mice, we find that a non-degree-corrected hierarchical architecture provides the most parsimonious description of the functional connectome. Importantly, the inferred posterior landscape is not dominated by a single configuration, but instead comprises multiple distinct and co-dominant organizational schemes.At the mesoscale, these hierarchical communities are anatomically grounded yet systematically reorganize canonical resting-state networks: primary sensory systems remain cohesive, whereas higher-order association networks are fractionated into multiple interacting sub-circuits. This global structural variation is driven by structured variability at the community level, where integrative systems exhibit variable regional affiliations while sensory systems act as structurally stable anchors.Together, these findings suggest that the resting-state connectome is best described as a distribution over alternative, yet co-dominant, organizational configurations. This perspective reconciles inconsistencies across previous studies and supports a view of brain organization as inherently degenerate, providing a latent repertoire of network configurations that may underlie adaptive information routing and dynamic functional reconfiguration.

PMID:42282699 | PMC:PMC13251934 | DOI:10.64898/2026.06.01.729443

bioRxiv [Preprint]. 2026 Jun 3:2026.05.31.729141. doi: 10.64898/2026.05.31.729141.

ABSTRACT

What does the brain do during the continuous, varied experience of watching a story unfold? One account holds that the brain traverses a finite repertoire of recurring states, but whether that repertoire is a stable property of the individual or is reshaped by each new experience has not been tested across diverse naturalistic content within the same person. We characterized the dynamic brain-state repertoire in six individuals who watched the television series Friends across its six seasons during fMRI (up to ∼146 episodes, ∼54 hours per person). For each individual we fit a sticky hierarchical Dirichlet process hidden Markov model across all episodes, discovering brain states (recurring whole-brain activity patterns with characteristic coupling) without pre-specifying their number. Each individual's brain visited roughly forty-five states arrayed along a continuous recurrence gradient, from states active in nearly every episode to episode-specific ones, with no sharp division between them. The repertoire was heterogeneous in why its states recurred: a minority locked to scan-run structure, the majority remaining eligible for content. Transitions were organized by the functional-connectivity similarity between states (per-individual Spearman ρ = 0.33-0.55) and, in most individuals, respected resting-state network boundaries. Episode content was associated with which states the brain occupied moment to moment. The recurrence ordering discovered in Friends transferred to state occupancy during other social-narrative films (five of six individuals) and attenuated as stimuli departed from that class, weakening for visual-only reading and audio-only listening. Across diverse narrative experience, the dynamic repertoire is a property of the individual: content varies which states are visited and when, not which states exist.

PMID:42282603 | PMC:PMC13252121 | DOI:10.64898/2026.05.31.729141

Sports Med Health Sci. 2025 Aug 6;8(4):407-425. doi: 10.1016/j.smhs.2025.07.008. eCollection 2026 Jul.

ABSTRACT

PURPOSE: Neuroimaging studies show that the functional connectivity of the brain changes with age. Resting state functional connectivity (rsFC) in the brain appears to decrease with aging in key networks associated with higher order thinking and effective emotional regulation. Interventions that potentially preserversFC in the brain include 1) physical activity and 2) contemplative practice commonly referred to as mindfulness. The present narrative review aims to summarize the literature concerning the effect of interventions involving exercise, mindful movement, and purely mindfulness-based training on rsFC.

METHODS: Search terms focused on identifying multi-day exercise, mindfulness, or mindful-movement interventions in non-clinical adult populations that included a control group and both pre- and post-assessment of brain rsFC.

RESULTS: Thirty studies were reviewed. Assessed methodological factors that potentially impact findings included subject sample size, scan time length, brain regions targeted for analyses, intervention length and intensity, population characteristics, and differences in sleep quantity/quality. Most studies reported changes in rsFC related to interventions with most observed changes found within the default mode, executive control and salience networks of the brain. However, the largest and most methodologically rigorous study found minimal associations between rsFC and either exercise or mindfulness.

CONCLUSION: Given the inconsistent results found in this review, caution is warranted in the interpretation of changes in rsFC attributable to exercise and mindfulness. This review highlights key factors likely to contribute to differences in reported outcomes. Methodological consistency in fMRI acquisition, data preparation, and analytical approaches are crucial to improve reproducibility and allow for comparison and aggregation.

PMID:42282450 | PMC:PMC13250210 | DOI:10.1016/j.smhs.2025.07.008

Res Sq [Preprint]. 2026 Jun 4:rs.3.rs-9900613. doi: 10.21203/rs.3.rs-9900613/v1.

ABSTRACT

Understanding the functional organization of the primate cortex requires metrics that capture both the temporal and topological dimensions of functional connectivity. Here we propose the spatial connectivity for local homogeneity in cortex (SoHo), a vertex-wise, continuous metric that quantifies the degree to which a cortical vertex and its immediate neighbors share similar spatial profiles of whole-brain functional connectivity. We validated SoHo using large-scale wakeful resting-state fMRI datasets from the Human Connectome Project (HCP) and the NIH Marmoset Brain Mapping Project. In humans, SoHo values showed a striking correspondence with the parcellation boundaries of the HCP multimodal atlas, with low-value regions consistently aligning with areal boundaries. Higher-order association areas exhibited lower SoHo values (functional diversity), while primary sensorimotor areas demonstrated higher values (functional uniformity). Cross-species SoHo mapping revealed that this primary-to-association gradient is evolutionarily conserved across primates, alongside species-specific adaptations in frontoparietal and motor regions. By capturing the local concordance of spatial fingerprints of whole-brain connectivity, SoHo bridges discrete parcellation schemes and continuous models of brain function, offering new insights into primate brain organization and evolution.

PMID:42281994 | PMC:PMC13252542 | DOI:10.21203/rs.3.rs-9900613/v1

Res Sq [Preprint]. 2026 Jun 7:rs.3.rs-9683033. doi: 10.21203/rs.3.rs-9683033/v1.

ABSTRACT

While stable patterns of fMRI task-evoked brain activity and functional connectivity (FC) exist at the population level, a growing body of research emphasizes that variability exists across individuals. These differences define the critical idiosyncrasies in cognition and behavior across individuals that make individuals unique. Resting-state fMRI data (60 minutes) were examined from 1012 participants from the HCP dataset of healthy adults between the ages of 22 and 37. Functional connectivity was estimated between 360 regions, and variability was defined by each individual's mean correlational distance (MCD) to all other participants. High MCD indicated a more 'idiosyncratic' connectivity pattern deviating from the group pattern. Hierarchical regression was used to determine predictors of variability in FC. The base model (demographics, sleep, sex, brain volume) explained 9.22% of the variance in heterogeneity in functional connectivity. Increased variance was explained by cognition, squared cognition, and NEO personality scores, while emotional scores and fitness explained no additional variance. The final model explained 11.9% of the variance in MCD. Low MCD (i.e., being closer to average) was associated with higher BMI, greater crystalized cognitive scores, more positive emotional valence, and NEO Agreeableness. Greater variability was associated with age, brain volume (potentially a sex difference), and NEO Extroversion. The model underestimated variability in the highest MCD participants, suggesting unexplained factors in highly variable individuals. Differences were observed between males and females, and monozygotic twins showed similar variability, suggesting a genetic component. These results suggest benefits for a connectivity pattern being more similar to the group average.

PMID:42281972 | PMC:PMC13252532 | DOI:10.21203/rs.3.rs-9683033/v1

Nutrients. 2026 May 23;18(11):1670. doi: 10.3390/nu18111670.

ABSTRACT

Background/Objectives: Intentional inhibition reflects voluntary control abilities and is assumed to be an indicator of overweight. The medial frontal cortex is an important brain region associated with intentional inhibition. Nevertheless, it is uncertain whether being overweight is connected to impaired food-related intentional inhibition (FII), and if so, what its underlying neural correlates are. The present study therefore aims to provide increased support for overweight due to impairment of FII. Methods: Firstly, 55 overweight and 45 normal-weight college students (Sample 1) were instructed to perform a go/no-go/choose task, which included a resting-state fMRI. Neural correlates of FII were examined using regional homogeneity (ReHo) analyses. Subsequently, an additional 180 undergraduates (87 overweight and 93 normal-weight; Sample 2) were examined to ascertain the differences in resting-state functional connectivity (rsFC) between overweight and normal-weight participants. The study also investigated whether restrained eating mediated the effect of rsFCs on one-year body index changes. Results: FII demonstrated a positive correlation with the cerebellum, inferior temporal gyrus, orbitofrontal cortex, inferior frontal gyrus, and cingulate gyrus. Additionally, in comparison with participants with normal weight, overweight participants demonstrated diminished rsFC between the FII-related areas and the postcentral gyrus, while heightened rsFC strengths were found between these areas and the middle temporal gyrus and precuneus. Furthermore, mediation analyses demonstrated that cingulate-precuneus connectivity is linked to fat mass index change a year later through restrained eating. Conclusions: FII was associated with connectivity between brain regions involved in inhibitory control and maladaptive eating. Furthermore, we investigated how these connectivity patterns could potentially affect future body fat loss through restrained eating.

PMID:42280314 | DOI:10.3390/nu18111670

Diagnostics (Basel). 2026 May 25;16(11):1619. doi: 10.3390/diagnostics16111619.

ABSTRACT

Background: Chemotherapy-induced peripheral neuropathy (CIPN) is a common, disabling toxicity with no validated biomarkers. MRI-based functional neuroimaging could offer insight into central pain processing and may reveal reproducible brain signatures of CIPN. Methods: Following PRISMA 2020 (PROSPERO: CRD420251132102), we systematically reviewed whole-brain MRI studies in adult cancer patients with CIPN. Eligible MRI techniques included task-based fMRI, resting-state fMRI, perfusion MRI, and structural MRI. Data were synthesized through voxelwise activation likelihood estimation (ALE), systems-level region-of-interest (ROI) mapping, and proportion meta-analysis of regional involvement. Results: Of 2488 screened records, five observational studies were included. The voxelwise ALE analysis did not identify clusters surviving correction, but dispersed foci appeared within the default mode network (DMN), prefrontal executive cortex, and primary sensorimotor regions, suggesting the engagement of these pain-processing networks. ROI synthesis confirmed consistent alterations in the DMN and executive prefrontal and sensorimotor cortices in CIPN patients compared with controls, while the brainstem/periaqueductal gray and cerebellum were rarely implicated. Proportion meta-analysis further quantified these differences: CIPN patients showed altered involvement in 30% (95% CI 0.16-0.48) of contrasts, with the highest frequencies in the DMN (50%), sensorimotor (33%), and executive prefrontal regions (33%). By contrast, control-higher contrasts were less frequent (10%, 95% CI 0.03-0.27), highlighting CIPN-related increases particularly in self-referential and somatosensory networks. Conclusions: Across analytic approaches, CIPN is characterized by reproducible alterations in the DMN and executive prefrontal and sensorimotor networks. These central pain signatures represent promising MRI-based biomarkers for identifying and monitoring CIPN in oncology.

PMID:42279487 | DOI:10.3390/diagnostics16111619