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Electroencephalographic evidence of cortical network disruption preceding overt cardioinhibition during tilt-induced reflex syncope.

OBJECTIVE: Reflex syncope is a common cause of transient loss of consciousness. However, the early cerebral mechanisms underlying cardiovascular changes remain poorly understood. Our objective was to investigate early cerebral changes by quantitatively analyzing EEG activity preceding overt cardioinhibition during tilt-induced reflex syncope. METHODS: EEG recordings from patients undergoing tilt testing were retrospectively analyzed. Patients who experienced reflex syncope were compared to those who did not. Spectral and functional connectivity analyses were performed across baseline, pre-cardioinhibition, and syncopal phases. RESULTS: Prior to the onset of cardioinhibitory pathological reflex, a significant increase in theta-band spectral power was observed in the right temporal region, accompanied by a widespread increase in functional connectivity within the same frequency band. These findings suggest the involvement of brain networks before cardioinhibition. CONCLUSIONS: EEG changes in the theta band (power and functional connectivity) were observed before overt cardioinhibition during tilt-induced reflex syncope. SIGNIFICANCE: Our findings support the hypothesis of cortical processing preceding cardioinhibition in reflex syncope. EEG may represent a valuable complementary tool for improving the understanding and diagnosis of these events.

Humans

Cerebellar iTBS enhances gait adaptation by modulating cortical sensorimotor network dynamics: a randomized controlled trial.

Gait adaptation enables individuals to maintain locomotor stability under persistent perturbations. Although the cerebellum is critical for sensory prediction error-based (SPE) adaptation, how cerebellar neuromodulation reshapes cortical sensorimotor networks to enhance gait adaptation remains unclear. This study investigated the behavioral effects and underlying cortical neurodynamic mechanisms of cerebellar intermittent theta-burst stimulation (iTBS) on gait adaptation. Thirty-two healthy adults received either active or sham cerebellar iTBS. Participants performed a split-belt treadmill adaptation task before and after intervention. Cortical responsiveness was evaluated using TMS-evoked EEG over primary motor cortex (M1), while resting-state EEG was analyzed to assess spectral power and directional functional connectivity. Compared to sham, cerebellar iTBS significantly enhanced gait adaptation, evidenced by a faster adaptation rate (p = 0.035) and enhanced Early Adaptation SLS (p = 0.011), without altering initial perturbation responses or post-adaptation outcomes. The iTBS increased TMS-evoked α (p = 0.031) and γ (p = 0.022) power in M1, while the α power was correlated with faster adaptation (r = 0.526, p = 0.002). Furthermore, iTBS strengthened PPC-to-M1 directed connectivity in the β (p = 0.025) and γ (p = 0.013) bands. Enhanced parieto-motor directionality were positively associated with adaptation rate (β: r = 0.515, p = 0.003; γ: r = 0.463, p = 0.009). These findings suggest that cerebellar iTBS facilitates gait adaptation by modulating cortical responsiveness and directional sensorimotor network connectivity, providing multi-level neurodynamic evidence for the cerebello-cortical modulation during gait adaptation and offering a strong physiological rationale for targeted neuromodulation in gait rehabilitation strategies.

Humans

Repetitive transcranial magnetic stimulation in functional motor disorders: A systematic review of effects and targets.

OBJECTIVE: To evaluate the effectiveness, safety, and potential mechanistic implications of repetitive transcranial magnetic stimulation (rTMS) in adults with functional motor disorders (FMD), focusing on possible phenotype-specific responses and stimulation protocols. METHODS: Seven databases were searched from inception to July 2026. Randomised and non-randomised interventional studies were included. Risk of bias and evidence certainty were assessed using PEDro, RoB 2, JBI tools, and GRADE. Because of substantial clinical and methodological heterogeneity, findings were synthesised qualitatively. RESULTS: Fourteen studies were included. The primary motor cortex was targeted in 11 studies. Functional tremor showed the most consistent evidence with inhibitory stimulation: one small sham-controlled trial found a significant group-by-time effect on tremor severity (p = 0.007), while an uncontrolled prospective series reported 40 % reduction in postural tremor amplitude (p = 0.05). Evidence for functional weakness was conflicting: excitatory M1 stimulation increased objective strength by 25 % versus 10 % with sham (p = 0.004), whereas the largest inhibitory sham-controlled trial found no benefit (p = 0.80). No severe adverse events were reported, but safety reporting was incomplete. GRADE certainty was moderate for tremor and very low for all other outcomes. CONCLUSIONS: Current evidence is insufficient to establish the efficacy of rTMS in FMD or to recommend phenotype-specific protocols. Preliminary findings support further investigation of inhibitory stimulation for functional tremor, whereas evidence for excitatory stimulation in functional weakness remains uncertain. SIGNIFICANCE: The possible interaction between phenotype and stimulation direction is hypothesis-generating. rTMS should currently be considered an experimental, context-sensitive adjunct within multidisciplinary care, pending adequately powered phenotype-stratified sham-controlled trials. Prospero Registration Number: CRD420251250969.

Humans

Novelty seeking and rapid symptom improvement across active and sham accelerated iTBS conditions: A pooled individual-patient data analysis.

INTRODUCTION: Major depressive disorder (MDD) is highly prevalent and often treatment-resistant. Accelerated intermittent theta burst stimulation (aiTBS) is a promising intervention for treatment-resistant depression (TRD), though outcomes vary. Personality traits have been examined in relation to rTMS outcomes, yet their role in aiTBS remains underexplored. This pooled individual-patient-data analysis of two randomized, sham-controlled trials examined associations between baseline Temperament and Character Inventory (TCI) traits and one-week symptom change, and whether they differed by condition. METHODS: The left dorsolateral prefrontal cortex was targeted for 20 sessions over 4 days. Personality was assessed with the TCI, depression severity with the 17-item Hamilton Depression Rating Scale (HDRS-17). TCI-symptom-change associations were examined with a robust linear mixed-effects model, adjusting for age, gender, repeated measurements, and study membership. RESULTS: 104 participants were included (M/F 45/59; mean age 40.9 ± 12.7; active/sham 50/54). The model yielded a Time × Novelty Seeking interaction (β = -1.70, p = 0.021): higher baseline Novelty Seeking was associated with faster symptom reduction, without a between-arm difference. However, the interaction did not survive Holm correction across 14 trait-interaction tests (adjusted p = 0.294) and is therefore exploratory. No other interaction reached the uncorrected threshold. CONCLUSIONS: Higher baseline Novelty Seeking showed a nominal association with faster symptom reduction, without a difference between active and sham conditions. Because it did not survive multiplicity correction and was not reproduced in within-arm analyses, it is preliminary and may reflect contextual or nonspecific processes. Independent replication is required before temperament assessment can be clinically informative.

Humans

Cross-tissue multi-omics integration highlights BPHL and mitochondrial targets in Alzheimer's disease.

BACKGROUND: Mitochondrial dysfunction is a hallmark of Alzheimer's disease (AD), yet specific molecular targets remain to be fully characterized. METHODS: A summary-data-based Mendelian randomization (SMR) framework integrated AD genome-wide association study (GWAS) statistics (39,918 cases) with blood DNA methylation quantitative trait loci (mQTL), gene expression (eQTL), and protein (pQTL) data for 1136 mitochondria-related genes. Associations were assessed using Bayesian colocalization and HEIDI testing. Tissue relevance was evaluated in four brain regions (hippocampus, amygdala, cortex, frontal cortex) using GTEx and external transcriptomic datasets. RESULTS: Screening identified eight candidates supported across blood mQTL and eQTL layers. Stepwise central nervous system (CNS) evaluation singled out biphenyl hydrolase-like (BPHL) as the consistent candidate. Higher genetically predicted BPHL expression was associated with reduced AD risk across the hippocampus (OR=0.920, 95% CI 0.873-0.970), amygdala (OR=0.925, 95%CI 0.880-0.973), cortex (OR=0.943, 95% CI 0.908-0.978), and frontal cortex (OR=0.938, 95%CI 0.901-0.976). These findings aligned with protein-protein interactions connecting BPHL to respiratory complexes and lower BPHL expression in independent AD brains. Functional enrichment converged on oxidative phosphorylation pathways. CONCLUSIONS: By integrating multi-omics data with tissue-specific validation, this study nominates BPHL as a consistent protective candidate in the brain. These findings provide genetic support for mitochondrial molecular perturbations in AD, offering insights for future validation.

Alzheimer Disease

Dual-tasking reveals severity-dependent reorganization of cortical beta energy landscapes in Parkinson's disease.

Dual-task impairment is a hallmark of Parkinson's disease (PD), yet the large-scale neural mechanisms underlying postural-motor interference remain poorly understood. In particular, it is unclear how cortical network dynamics reorganize across disease severity when postural control competes with concurrent task demands. This study investigated EEG-derived beta-band cortical energy landscapes in healthy older adults, early-stage PD, and mid-stage PD during single- and dual-task conditions. Dual-task behavioral cost increased with disease severity for concurrent manual performance (p&#xa0;<&#xa0;0.001), whereas a quadratic pattern was observed for postural performance. Energy landscape analysis revealed severity-dependent reconfiguration of cortical beta dynamics. Dual-task-related landscape changes in effective network flexibility (&#x394;Neff), landscape geometry (&#x394;Evar and &#x394;Gmag), and dominant low-energy attractor organization (&#x394;Low mass and &#x394;Low area) showed significant monotonic trends (p&#xa0;<&#xa0;0.05), reflecting progressive constrained cortical network dynamics with advancing PD severity. In addition, dual-task-related landscape alterations were associated with clinical severity, as indexed by Hoehn and Yahr stage (|r|&#xa0;=&#xa0;0.353-0.423, p&#xa0;=&#xa0;0.016-0.048), and showed associations with motor impairment, as measured by MDS-UPDRS part III scores (|r|&#xa0;=&#xa0;0.333-0.455, p&#xa0;=&#xa0;0.009-0.063). These findings demonstrate that dual-task demands induce severity-dependent reconfiguration of cortical beta energy landscapes in PD. Energy landscape geometry may capture systems-level neural constraints associated with dual-task susceptibility in PD, providing a physiologically grounded framework to characterize disease-related functional vulnerability.

Humans

Dissociating behavioral, neural and experiential effects of prefrontal HD-tDCS during conflict resolution.

Inconsistent evidence regarding the cognitive effects of transcranial direct current stimulation (tDCS) highlights the need for more comprehensive approaches to assess its impact. This study aimed to investigate the effects of high-definition tDCS (HD-tDCS) on conflict resolution by combining behavioral, neural, and subjective experience measures. Sixty participants were randomly assigned to anodal, cathodal, or sham HD-tDCS groups and completed a 30-min flanker task. EEG was recorded during the first and last blocks (without stimulation), while stimulation was applied during the intermediate blocks of the task. Using a multidimensional methodological approach including Drift-Diffusion Modeling (DDM), EEG spectral analysis, Lempel-Ziv complexity, and Temporal Experience Tracing (TET), we assessed the cognitive, neural, and phenomenological effects of stimulation. Behavioral results indicated no significant improvements in reaction times or accuracy across the stimulation groups. Similarly, DDM parameters showed no effect of HD-tDCS on latent cognitive processes. However, EEG data revealed a significant reduction in neural complexity in the anodal group during resting-state, suggesting a stabilization or reorganization of neural dynamics. Subjective experience analysis identified two distinct clusters of task-related feelings, though time spent in these experiential states did not differ between groups. Interestingly, sensation of stimulation was significantly higher for anodal stimulation than sham when analyzed as a single dimension. Despite null behavioral effects, this study provides important insights into the neural and subjective responses to HD-tDCS and highlights the value of integrating complementary multidimensional approaches to better characterize brain stimulation effects. These findings contribute to the ongoing debate about the efficacy of tDCS in cognitive enhancement.

Humans

Acupuncture improves depressive symptoms and prefrontal cortical function in mild to moderate depressive disorder: A randomized sham-controlled trial and fNIRS study.

BACKGROUND: Depressive disorder is a common mental illness associated with substantial functional impairment. Although pharmacotherapy is widely used, its effectiveness is often limited by adverse effects and poor adherence. Acupuncture has been increasingly applied as a complementary treatment for depression, and its neurobiological characteristics remain unclear. OBJECTIVE: This randomized, sham-controlled trial aimed to evaluate the clinical efficacy of acupuncture for mild to moderate depressive disorder and to investigate its effects on prefrontal cortical function using functional near-infrared spectroscopy (fNIRS). METHODS: Patients with mild to moderate depressive disorder were randomly assigned to a real acupuncture (RA) group or a sham acupuncture (SA) group and received standardized treatment for 8 weeks. Clinical outcomes were assessed using the Self-Rating Depression Scale (SDS), Self-Rating Anxiety Scale (SAS), Short Form-36 Health Survey (SF-36), and a traditional Chinese medicine syndrome score. A subset of participants underwent fNIRS assessment during resting-state and task-based conditions to evaluate prefrontal cortical activation and functional connectivity. RESULTS: Compared with baseline, the RA group showed significant reductions in SDS and SAS scores and significant improvements in SF-36 emotional domains, with effects emerging at Week 4 and persisting up to 12 weeks after treatment. Improvements were greater and more stable in the RA group than in the SA group. fNIRS analyses revealed enhanced activation in dorsolateral and medial prefrontal regions and strengthened prefrontal functional connectivity following acupuncture, whereas neural changes in the SA group were limited. CONCLUSION: Acupuncture is effective for improving depressive and anxiety symptoms and quality of life in patients with mild to moderate depressive disorder. Modulation of prefrontal cortical activation and connectivity may underlie its antidepressant effects.

Humans

The effect of combining visuo-vestibular exercises with manual therapy and exercise on sensorimotor function in chronic neck pain: A randomized controlled trial.

OBJECTIVE: To investigate whether adding visuo-vestibular exercises to standard manual therapy and exercise produces superior improvements in sensorimotor function, pain, balance, and functional disability in adults with chronic neck pain. METHODS: This prospective, randomized controlled trial enrolled 58 adults with chronic neck pain (&#x2265;3 months) allocated to a manual therapy and exercise group (MtE; n&#x202f;=&#x202f;29) or MtE plus visuo-vestibular exercises (MtE-VVE; n&#x202f;=&#x202f;29). Both groups completed 12 supervised sessions over six weeks with a daily home exercise programme. Outcomes were assessed at baseline, 6 weeks, and 12 weeks, and included pain intensity (Visual Analog Scale [VAS]), upper extremity reaction time, computerized posturography, the Neck Disability Index (NDI), and cervical muscle endurance. RESULTS: Fifty-four participants (27 per group) completed the study. Both groups improved significantly across all outcomes (p&#x202f;<&#x202f;0.001). At 12-week follow-up, the MtE-VVE group demonstrated superior outcomes: activity-related pain was reduced by an additional 2.00&#x202f;cm (95% CI: 0.75-3.25; p&#x202f;=&#x202f;0.005), bilateral reaction time improved by 1.70&#x202f;s (p&#x202f;=&#x202f;0.001), eyes-open mediolateral sway decreased by 0.50&#x202f;mm (p&#x202f;<&#x202f;0.001), NDI score was 6.30 points lower (95% CI: 3.42-9.18; p&#x202f;<&#x202f;0.001), and cervical flexion and extension endurance improved by 12.00&#x202f;s and 27.70&#x202f;s, respectively (p&#x202f;&#x2264;&#x202f;0.020). CONCLUSION: Adding visuo-vestibular exercises to standard manual therapy and exercise produces clinically meaningful and sustained improvements in activity-related pain, sensorimotor function, postural control, and functional disability in adults with chronic neck pain, and may be recommended as an effective adjunctive intervention.

Humans

Dissociable neural mechanisms of cognitive enhancement through transcranial stimulation and behavioral training.

BACKGROUND: Transcranial direct current stimulation (tDCS) and adaptive working memory (WM) training are promising cognitive enhancement approaches; however, their neural mechanisms and potential synergies remain poorly understood. OBJECTIVE: We directly compared how tDCS and WM training modulate neural oscillations during WM performance and examined whether combining both interventions produces additive effects. METHODS: We randomized 112 healthy adults into four groups: control (sham tDCS&#xa0;+&#xa0;non-adaptive 1-back), tDCS-only (active tDCS&#xa0;+&#xa0;non-adaptive 1-back), training-only (sham tDCS&#xa0;+&#xa0;adaptive n-back training), or combined (active tDCS&#xa0;+&#xa0;adaptive training). Participants underwent five daily intervention sessions. We recorded high-density EEG during transfer n-back tasks at baseline, post-intervention, and one-week follow-up. RESULTS: All active interventions improved WM performance relative to the control group, with the combined group showing the largest gains (n-back accuracy: +15.6% vs.&#xa0;+&#xa0;10.1% tDCS-only, +9.7% training-only, +0.7% control; all p&#xa0;<&#xa0;0.001). Critically, tDCS selectively increased gamma-band (30-50&#xa0;Hz) power in the frontal and parietal regions (cluster p&#xa0;=&#xa0;0.018, d&#xa0;>&#xa0;1.0), whereas WM training enhanced frontal theta-band (4-8&#xa0;Hz) power and theta-gamma phase-amplitude coupling (both cluster p&#xa0;<&#xa0;0.012, d&#xa0;>&#xa0;0.85). The combined group exhibited both neural signatures. Brain-behavior correlations revealed dissociable relationships: gamma increases predicted n-back accuracy improvements (r&#xa0;=&#xa0;0.61, p&#xa0;<&#xa0;0.001), whereas theta enhancements correlated with operation span gains (r&#xa0;=&#xa0;0.58, p&#xa0;=&#xa0;0.002). CONCLUSIONS: tDCS and WM training enhance cognition through distinct yet complementary neural mechanisms: tDCS via gamma-mediated cortical excitability and WM training via theta-mediated cognitive control. These findings provide neurophysiological evidence for multimodal enhancement strategies that target parallel pathways within WM networks.

Humans

A single session of high-definition transcranial direct current stimulation does not modulate effects of knee two-point discrimination training or sensorimotor function in healthy adults: Double-blind randomised controlled trial.

BACKGROUND: Benefits of sensory-training interventions on sensorimotor outcomes are inconsistent, and it is unclear whether transcranial direct current stimulation (tDCS) can enhance proprioception, which is fundamental to neuromuscular control. Existing evidence is dominated by upper-limb studies, so transferability to the knee is unclear. This study investigated whether a single session of anodal high-definition (HD)-tDCS, alone or combined with brief two-point discrimination (TPD) training, enhances knee sensorimotor function and performance in healthy adults. METHODS: In a double-blind randomised-controlled trial, 57 healthy participants received (1) 20-min, 1&#xa0;mA anodal HD-tDCS over the knee primary somatosensory (S1) map or sham stimulation, and (2) 15-min knee TPD training or no training. Knee somatosensory, sensorimotor, and functional performance measures were assessed pre- and immediately post-intervention. Three-way mixed-design ANOVAs, equivalence testing (smallest effect size of interest &#x3b7;2&#xa0;=&#xa0;0.02), Bayes factors, and linear mixed-effects models quantified effects. RESULTS: HD-tDCS, TPD training, and their sequential combination had no effect on any outcome measure (p&#xa0;&#x2265;&#xa0;0.05; &#x3b7;2&#xa0;&#x2264;&#xa0;0.015). Confidence intervals spanned equivalence bounds, and equivalence testing results were non-significant (p&#xa0;&#x2265;&#xa0;0.05). Bayes factors (<0.33) showed moderate evidence for the null (no effect). Mixed-effects modelling attributed &#x2264;8% of total variance to intervention fixed effects, with the remainder captured by participant-level random effects. CONCLUSION: A single 20-minute session of 1&#xa0;mA HD-tDCS, with or without brief TPD training, does not acutely modify knee somatosensory, sensorimotor, or functional performance in healthy adults. Existing evidence at the hand may not translate to the lower limb. Future work should investigate higher-dose, multi-session, task-concurrent, or network-targeted strategies in clinical populations.

Humans

Corticosteroids as adjunctive therapy to standard treatment in Kawasaki disease: a GRADE-assessed systematic review and meta-analysis of randomized controlled trials.

UNLABELLED: Kawasaki disease (KD) is an acute systemic vasculitis and the leading cause of acquired heart disease in children in developed countries. While IVIG plus aspirin remains standard treatment, 10-20% of patients are IVIG-resistant and face an elevated risk of coronary artery abnormalities. Corticosteroids have been explored as adjunctive therapy, though evidence on their benefit remains inconsistent. To assess the efficacy and safety of adjunctive corticosteroids in Kawasaki disease across key clinical outcomes.&#xa0;This PRISMA 2020-compliant systematic review and meta-analysis included RCTs identified through database searches up to April 2026. Risk of bias was assessed using Cochrane RoB 2.0. Data were pooled using random-effects models to estimate risk ratios (RRs) and mean differences (MDs) with 95% CIs. Subgroup analyses, leave-one-out sensitivity analyses, and GRADE certainty appraisal were also performed.&#xa0;Eight studies (n&#x2009;=&#x2009;4106) were included. No significant differences were found in coronary artery abnormalities (CAA) within 1&#xa0;month (RR 0.49, 95% CI 0.17-1.42), after 1&#xa0;month (RR 0.81, 95% CI 0.43-1.55), fever duration (MD&#x2009;-&#x2009;1.75, 95% CI&#x2009;-&#x2009;3.71 to 0.21), or adverse events (RR 1.08, 95% CI 0.57-2.07). Hospital stay was modestly shorter with corticosteroids (MD&#x2009;-&#x2009;0.99, 95% CI&#x2009;-&#x2009;1.86 to&#x2009;-&#x2009;0.11). Exploratory subgroup analyses suggested potential benefits with prednisolone-based and prolonged corticosteroid regimens for selected outcomes; however, these findings should be interpreted cautiously given multiple subgroup comparisons. Overall certainty of evidence was very low. CONCLUSION: &#xa0;Adjunctive corticosteroids did not significantly improve major outcomes in KD. Prednisolone-based regimens showed some promise, but high-quality trials are still needed before any firm conclusions can be drawn. WHAT IS KNOWN: &#x2022; Corticosteroids have been studied as adjunctive therapy for Kawasaki disease, but their effects on coronary outcomes and other clinical outcomes remain inconsistent. WHAT IS NEW: &#x2022; This meta-analysis found no significant improvement in major outcomes with adjunctive corticosteroids, although prednisolone-based and prolonged regimens may provide benefits for selected outcomes.

Humans

Awake Craniotomy for Eloquent Region Glioblastoma Classified by Tumor Location-A Retrospective and Prospective Cohort Study.

INTRODUCTION: The efficacy of awake craniotomy (AC) with intraoperative mapping for glioblastoma (GBM) in eloquent regions remains debated. This study aims to evaluate functional and survival outcomes of GBM patients undergoing AC stratified by tumor locations. METHODS: A combined retrospective (2015-2023, n&#x2009;=&#x2009;114: 43&#x2009;AC vs. 71 standard craniotomy) and prospective cohort (2023-2025, n&#x2009;=&#x2009;28: 13&#x2009;AC vs. 15 standard craniotomy) of GBM patients with motor/language-eloquent tumors was analyzed. Tumors were classified into motor subtypes (I: precentral gyrus; II: premotor/supplementary motor; III: internal capsule posterior limb; IV: other) and language subtypes (I: Broca's/precentral; II: postcentral/supramarginal gyrus; III: Wernicke's; IV: insular; V: other). Outcomes included extent of resection (EOR), postoperative motor/language recovery, overall survival (OS), and progression-free survival (PFS). RESULTS: The retrospective cohort demonstrated that AC has advantages in functional preservation across various motor/language subtypes. However, AC was associated with significantly deteriorated survival outcomes specifically in precentral gyrus GBMs. A prospective cohort study, enrolling only precentral gyrus GBMs for validation, yielded results consistent with the retrospective findings: worsened OS and PFS (OS: HR&#x2009;=&#x2009;3.223, p&#x2009;=&#x2009;0.0450; PFS: HR&#x2009;=&#x2009;2.374, p&#x2009;=&#x2009;0.0476); reduced EOR (AC:&#xa0;74.3%&#x2009;&#xb1;&#x2009;5.3%; standard craniotomy: 86.9%&#x2009;&#xb1;&#x2009;12.3%, p&#x2009;=&#x2009;0.0470); and better motor recovery. CONCLUSIONS: Functional preservation and survival outcomes of AC in GBM exhibited subtype-specific correlations with tumor locations. AC with intraoperative mapping effectively preserves neurological function in GBM patients. However, for tumors involving the precentral gyrus, the AC approach carries greater risks than benefits and should be considered with caution. TRIAL REGISTRATION: Strategic Intervention on Preserving Motor Function During Awake Craniotomy: NCT05143788. Strategic Intervention on Preserving Language Function During Awake Craniotomy: NCT05143775.

Adult

Comparison of the clinical efficacy, safety and EEG functional connectivity changes between 18-Hz rTMS and iTBS of accelerated dTMS treatment for major depressive disorder: a randomized controlled trial.

Although the antidepressant efficacy of 18-Hz deep transcranial magnetic stimulation (dTMS) has been validated, its prolonged treatment duration has considerable limitations for treatment capacity and patient adherence. Therefore, novel short-course protocols such as accelerated dTMS and intermittent theta burst stimulation (iTBS) present promising alternative options. Here we addressed the question of whether iTBS of accelerated dTMS achieves comparable therapeutic and electrophysiological effects to accelerated dTMS with the conventional 18-Hz rTMS protocol in patients with major depressive disorder (MDD). In a randomized controlled trial (n&#x2009;=&#x2009;73), participants received either 18-Hz rTMS of accelerated dTMS (rTMS-dTMS group), iTBS of accelerated dTMS (iTBS-dTMS group), or pharmacotherapy alone (drug group). Both dTMS protocols were administered twice daily for 10 days targeting the left lateral prefrontal cortex including the dorsolateral region. Results showed that Hamilton Depression Rating Scale (HAMD) score of the iTBS-dTMS group decreased significantly from 22.5&#x2009;&#xb1;&#x2009;3.7 before treatment to 8.2&#x2009;&#xb1;&#x2009;4.1 after treatment (t&#x2009;=&#x2009;15.900, p&#x2009;<&#x2009;0.001). HAMD score of the rTMS-dTMS group decreased significantly from 21.3&#x2009;&#xb1;&#x2009;2.9 before treatment to 8.0&#x2009;&#xb1;&#x2009;3.8 after treatment (t&#x2009;=&#x2009;17.232, p&#x2009;<&#x2009;0.001). The drug group also exhibited significantly improved patients' mood symptoms, and the HAMD score decreased from 24.7&#x2009;&#xb1;&#x2009;6.8 to 14.0&#x2009;&#xb1;&#x2009;5.0 (t&#x2009;=&#x2009;6.363, p&#x2009;<&#x2009;0.001). The treatment response rate was 85.7% in the iTBS-dTMS group and 76.9% in the rTMS-dTMS group, which was much higher than that of the drug group (42.1%). The remission rate was 50.0% in the iTBS-dTMS group and 42.3% in the rTMS-dTMS group, which was significantly higher than 10.5% of the drug group. We demonstrate here that both accelerated dTMS protocols significantly reduced HAMD scores, improved the response rates, and remission rates, outperforming pharmacotherapy alone. Resting-state EEG analysis further revealed unique frequency-specific functional connectivity (FC) modulation effects: the rTMS-dTMS group primarily exhibited weakened alpha-band functional connectivity within the fronto-occipital, fronto-temporal and fronto-central networks after treatment, whereas the iTBS-dTMS group predominantly demonstrated reduced theta-band functional connectivity within the fronto-parietal, fronto-occipital and fronto-temporal pathways after treatment. These findings indicate that iTBS of accelerated dTMS demonstrates comparable efficacy and tolerability to 18-Hz rTMS of accelerated dTMS, whilst inducing treatment-specific network-level neurophysiological alterations. In the rTMS-dTMS group, relative changes in FC between the frontal and temporal/precentral regions showed significant negative correlation with HAMD score reduction rates, while relative changes in FC between the frontal lobe and parietal lobe showed a significant positive correlation with the rate of HAMD score reduction for the iTBS-dTMS group. This study revealed novel mechanisms by which accelerated dTMS protocols modulate brain networks, providing evidence for the clinical application of accelerated iTBS-dTMS as an efficient, evidence-based treatment for MDD.

Humans

Complement component C4 and neuroimaging in psychiatry: A systematic review.

INTRODUCTION: Genomic, transcriptomic, and proteomic studies suggest that the complement system contributes to the pathophysiology of various psychiatric disorders partly through neurodevelopmental effects linked to C4A protein levels variations. We conducted a systematic review to characterize how brain micro- and macrostructure and connectivity vary with proxies of in vivo brain C4A protein levels in both psychiatric and general-population cohorts. METHODS: We used Medline, Web of Science, and Embase, and included all studies published before April 14, 2025. Inclusion criteria were: (1) inclusion of healthy controls and/or individuals with psychiatric disorders assessed according to recognized diagnostic manuals (DSM or ICD); (2) use of MRI-based neuroimaging; and (3) use of genomic, transcriptomic and/or proteomic approaches as proxies of in vivo brain C4A proteins levels. RESULTS: From 317 identified articles, 11 were included. Associations between C4A levels and brain structure were heterogeneous across regions. Only the mOFC, dlPFC, and entorhinal cortex were implicated in more than one study. Findings for the mOFC and dlPFC varied by the type of metrics and clinical status, whereas higher C4A levels were more consistently associated with smaller entorhinal cortex surface area and cortical thickness in pediatric, middle-aged, and older general-population cohorts. In addition, one study found higher genetically predicted C4A expression to be associated with higher TSPO levels. CONCLUSION: The limited number of available studies and their methodological heterogeneity make synthesis challenging. However, biological hypotheses such as excessive synaptic pruning or broader inflammatory effects on the brain may provide plausible explanatory frameworks for the reported associations.

Humans

Accurate quantification of canine mitochondrial DNA copy number from canine blood and brain samples.

Acute brain injury is difficult to evaluate in veterinary medicine and tools to investigate the potential involvement of mitochondrial involvement are limited. The brain is highly enriched in mitochondria and contains thousands of copies of mitochondrial DNA (mtDNA) per cell, but robust methods for quantifying mitochondrial DNA copy number (mtDNA-CN) in canine tissues are lacking. We describe the development of a quantitative real-time PCR assay for absolute measurement of mtDNA-CN which was validated in canine blood and brain tissue. To minimize amplification of nuclear mitochondrial insertion sequences (NumtS) and repetitive regions, species-specific oligonucleotide primers were designed following in silico genomic filtering. The assay was applied to a small pilot cohort comprising blood samples from dogs with and without acute brain injury (n&#xa0;=&#xa0;4-6 per group) and cerebral cortex samples (n&#xa0;=&#xa0;1 per group) to assess feasibility and biological plausibility. In non-brain injury dogs, blood mtDNA-CN ranged from 98 to 288 copies per nuclear genome (mean 193&#xa0;&#xb1;&#xa0;72), while values in brain-injured cases ranged from 163 to 228 copies per genome (mean 200&#xa0;&#xb1;&#xa0;33). Cerebral cortex samples exhibited higher mtDNA-CN than blood, consistent with known tissue-specific mitochondrial enrichment. In a single brain-injured case with serial sampling, mtDNA-CN increased over five days. This study presents a validated assay and pilot data for mtDNA-CN quantification in canine samples. While not powered for biomarker evaluation, this method may enable future studies of mitochondrial dynamics in canine brain injury and metabolic disease.

Animals

Retinal microstructural alterations as early phenotypes of depression in radiogenomics analysis.

BACKGROUND: With the increasing prevalence of depression, there is an urgent clinical need for early screening in depression. The retina offers a promising window for early screening in depression due to its rapid, non-invasive, objective, eye-brain correlated characteristics, but previous research has yielded conflicting alterations in retinal microstructure in depression. METHODS: We screened retinal optical coherence tomography and brain magnetic resonance imaging data in the UK Biobank to enroll 23,225 participants for retinal study of depression occurrence, and 1475 participants for the eye-brain association study. We also used genetic data (ID: ebi-a-GCST90014267 and ukb-d-20,448) from the Integrative Epidemiology Unit Open Genome-Wide Association Study for Mendelian randomization analysis. We used Cox regression to assess the association between retinal microstructure and depression risk, Mendelian randomization to infer causality, and mediation analysis to explore retina-brain pathway association. RESULTS: The Cox regression analysis showed that retinal ganglion cell-inner plexiform layer (GCIPL) thickness remained a significant predictor of depression. The Mendelian randomization analysis indicated a positive statistical association between GCIPL thickness and depression. Moreover, there was a significant positive correlation (all p&#xa0;<&#xa0;0.001) between the volume of specific depression-related brain regions and the GCIPL thickness. Adjusting for age, sex, and head size, the mediation analysis provided preliminary evidence for a potential anatomical pathway linking retinal GCIPL thickness to depression-related brain regions through primary visual cortex and secondary visual cortex volumes. CONCLUSION: Thickened retinal GCIPL is a potential early phenotype of depression and has a potential association pathway with depression-related brain regions using a radiogenomics approach.

Humans

Context-dependent functional diversity of dorsomedial posterior parietal neurons revealed by single-unit fMRI mapping during naturalistic viewing.

The dorsomedial posterior parietal cortex (dmPPC) plays an important role in episodic processing by integrating sensory, cognitive, and motor information across distributed brain systems. However, how individual dmPPC neurons participate in large-scale functional organization during naturalistic experience remains poorly understood. To address this question, we combined single-unit electrophysiology and awake fMRI in five rhesus macaques of both sexes viewing identical naturalistic video stimuli. Using single-unit fMRI mapping, we generated whole-brain neuron-BOLD functional maps by correlating individual neuronal activity with voxel-wise fMRI signals across the brain. We found that neuron-BOLD functional maps exhibited strong context-dependent organization, with neurons recorded during the same video context showing substantially greater similarity than neurons recorded during different video conditions. Compared with neuronal spiking activity or critical fMRI frames alone, neuron-BOLD functional maps more robustly captured contextual structure. Despite this shared large-scale organization, a substantial subset of neighboring neurons recorded simultaneously from the same electrode displayed markedly distinct whole-brain association patterns, revealing substantial local functional heterogeneity within the dmPPC. This local heterogeneity was not readily explained by waveform-based putative cell class or by opposing neuronal firing dynamics. In addition, distributed cortical and medial temporal regions exhibited highly context-dependent neuron-BOLD association patterns during naturalistic viewing. Together, these findings demonstrate that dmPPC neurons participate in dynamic and heterogeneous large-scale functional organization during naturalistic episodic processing. More broadly, this study establishes single-unit fMRI mapping as a framework for linking single-neuron activity to distributed whole-brain dynamics across contextual conditions.Significance Statement Using single-unit fMRI mapping, this study examined how individual dorsomedial posterior parietal cortex (dmPPC) neurons relate to large-scale brain activity during naturalistic video viewing in macaque monkeys. We found that neuron-BOLD functional maps exhibit strong context-dependent organization and capture contextual structure more robustly than neuronal spiking activity or fMRI frames alone. Despite this shared organization, a substantial subset of neighboring dmPPC neurons displayed markedly distinct whole-brain association patterns, revealing local functional heterogeneity that was not readily explained by waveform-based putative cell class or opposing firing dynamics. These findings provide insight into how local neuronal populations participate in distributed brain-wide functional organization during naturalistic episodic processing.

Journal Article