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Age-dependent reorganization of behavioral and striatal function in Cntnap2 knockout mice.

Autism spectrum disorder (ASD) is characterized by persistent deficits in social communication and the presence of restricted and repetitive behaviors. While ASD has a neurodevelopmental origin, it remains a lifelong condition, yet little is known about how its behavioral and neural features evolve across adulthood. Here, we investigated behavioral, synaptic, and structural alterations across the transition from early to mature adulthood in Cntnap2 knockout mice, a widely used model of ASD. Using a longitudinal behavioral approach combined with electrophysiological recordings and morphological analysis, we show that KO mice exhibit increased stereotyped and repetitive behaviors and reduced exploratory activity at both ages. However, detailed analysis of behavioral patterns revealed age-dependent differences, with early adult KO mice displaying increased behavioral persistence that later evolved into distinct patterns of behavioral sequences. These behavioral changes were associated with alterations in inhibitory synaptic transmission in the dorsolateral striatum (DLS), including changes in spontaneous inhibitory postsynaptic current (sIPSC) frequency and temporal structure. In parallel, mature adult KO mice showed structural remodeling of spiny projection neurons, characterized by increased distal dendritic arborization and age-dependent organization of dendritic spines. Together, our findings demonstrate that ASD-related alterations are not static but evolve across adulthood, revealing a multi-level reorganization of behavioral, synaptic, and structural features. These results highlight the importance of considering adulthood stages in ASD and provide new insights into the dynamic nature of the condition.

Animals

Insights from changes in NDEV biomarkers of metabolism: effects of PPARγ and GLP1 receptor agonists on brain metabolism.

BACKGROUND: Insulin resistance (IR) is implicated in central nervous system disorders, including depression and Alzheimer's disease (AD). METHODS: We analyzed biological samples from two cohorts of clinical trial participants: (1) participants with unremitted depression after six months of treatment as usual who received pioglitazone (PPARγ agonist, N = 12) or placebo and (2) middle-aged participants at genetic risk for AD who received liraglutide (glucagon-like peptide 1 [GLP1] receptor agonist, N = 15) or placebo. These cohorts, which previously showed treatment-related improvements in peripheral IR, were used to assess the effects of pioglitazone and liraglutide on CNS insulin signaling using neuron-derived extracellular vesicles (NDEVs) as biomarkers. We utilized biological samples to measure biomarkers of IR in NDEVs. Eleven Akt-mTOR pathway proteins were measured before and after 12 weeks of treatment in both groups. RESULTS: Participants who received pioglitazone experienced broader changes, with significant increases in GSK3β (Ser9), mTOR (Ser2448), and RPS6 (Ser235/Ser236; all P ≤ .02) compared with placebo, and 77% of participants showed mTOR (Ser2448) response. Participants who received liraglutide demonstrated significantly increased NDEV-associated phosphorylated Akt (Ser473) and mTOR (Ser2448; P = .04 and P = .025, respectively) compared with placebo, with 40% and 30% of participants in the liraglutide group showing biomarker response in both Akt (Ser473) and mTOR (Ser2448), respectively. These effects appeared relatively independent from changes in fasting plasma insulin and glucose concentration at 120-minutes during the oral glucose tolerance test. DISCUSSION: Our findings demonstrate CNS-specific biomarker responses to both PPARγ agonists and GLP1 receptor agonists.

Humans

ScRNA-seq analysis reveals the effects of nitrite stress on the endocrine system of the eyestalk in Litopenaeus vannamei.

Nitrite is a harmful substance generated in Litopenaeus vannamei farming systems, largely originating from the inadequate breakdown of surplus feed and shrimp feces. Its accumulation in the water can affect the growth and physiological functions of shrimp, damage the immune system, and even cause mass mortality, thus becoming a key environmental factor restricting the green development of the industry. Under nitrite stress, the eyestalk, as an important neuroendocrine regulatory center in crustaceans, participates in the stress adaptation of the organism and exerts a protective effect by regulating energy metabolism and immune function. However, the molecular regulatory mechanism of the eyestalk in response to nitrite stress remains unclear. In this study, single-cell RNA sequencing (scRNA-seq) technology was used to analyze the heterogeneity of eyestalk cells in L. vannamei under nitrite stress. A total of 18, 394 high-quality cells were obtained, and six major cell subpopulations, including Neurosecretory cell, Motor neuron, Sensory neuron, Interneuron, Neurogliocyte, and Support cell, were identified. Differential expression analysis identified 839 differentially expressed genes, and different cell types showed distinct specific responses to nitrite stress. Functional enrichment analysis indicated that pathways such as glycolysis, oxidative phosphorylation, ribosome function, and endoplasmic reticulum protein processing were significantly activated, while signal transduction and DNA repair-related pathways were inhibited. Further analysis revealed that nitrite stress could induce mitochondrial function changes and trigger oxidative stress, thereby affecting the neuroendocrine system function of the eyestalk. This study provided insights into transcriptomic responses of the eyestalk to nitrite stress at the single-cell level, laying a theoretical foundation for the management of aquaculture environments.

Animals

[Clinical efficacy and safety of electroacupuncture at the motor area for Parkinson's disease with musculoskeletal pain: a randomized controlled trial].

OBJECTIVE: To observe the clinical efficacy and safety of electroacupuncture (EA) at the motor area for Parkinson's disease (PD) with musculoskeletal pain. METHODS: Fifty-eight patients with PD accompanied by musculoskeletal pain were randomly assigned to an EA group (29 cases, 1 case dropped out) and a sham EA group (29 cases, 1 case dropped out). The EA group was treated with EA at the motor area contralateral to the painful side (for bilateral pain, the left motor area was selected), using disperse-dense wave (2 Hz/20 Hz), with a current intensity of 1-2 mA, and needles were retained for 30 min. The sham EA group was treated with sham EA at non-acupoint area located 5-20 mm posterior to the motor area contralateral to the painful side. The connection mode was the same as that in the EA group, but no electrical current was delivered, and the needles were retained for 30 min. Both groups were treated once daily for 5 consecutive days. Visual analogue scale (VAS) for pain, unified Parkinson's disease rating scale part &#x2162; (UPDRS-&#x2162;), 24-item Hamilton depression rating scale (HAMD-24), Hamilton anxiety rating scale (HAMA), and 39-item Parkinson's disease questionnaire (PDQ-39) scores were evaluated before treatment, immediately after treatment, and at 2 and 4 weeks after treatment completion in the two groups. Safety was also assessed in the two groups. RESULTS: In both groups, VAS scores for pain after treatment and at 2 and 4 weeks after treatment completion were lower than those before treatment (P<0.01, P<0.05). VAS scores for pain in the EA group were lower than those in the sham EA group after treatment and at 2 and 4 weeks after treatment completion (P<0.05). In the EA group, UPDRS-&#x2162;, HAMD-24, HAMA, and PDQ-39 scores after treatment and at 2 and 4 weeks after treatment completion were lower than those before treatment (P<0.05, P<0.01). In the sham EA group, there were no statistically significant differences in UPDRS-&#x2162;, HAMD-24, HAMA, and PDQ-39 scores at any post-treatment time point compared with those before treatment (P>0.05). There were no statistically significant differences in UPDRS-&#x2162;, HAMD-24, HAMA, and PDQ-39 scores between the two groups at any post-treatment time point (P>0.05). No serious adverse events occurred during the trial. CONCLUSION: EA at the motor area could reduce pain intensity in patients with PD accompanied by musculoskeletal pain, and improve pain-related motor symptoms, emotional status, and quality of life, with a favorable safety profile.

Humans

Efficacy of citicoline as an add-on therapy in Parkinson's disease: a randomized, double-blind trial.

BACKGROUND: Citicoline is a promising therapeutic option for improving both motor and non-motor symptoms in Parkinson's disease (PD) beyond levodopa and other standard dopaminergic treatments. OBJECTIVES: The CITIPARK study evaluated the efficacy and safety of citicoline in improving clinical outcomes and quality of life (QOL) in PD patients on dopaminergic therapies. METHODS: The randomized, double-blind, multicenter trial compared citicoline (1000&#x202f;mg/day intramuscular, two six-week cycles) with placebo for 24 weeks in PD under stable medications. The primary endpoint was change in Movement Disorder Society-Unified PD Rating Scale (MDS-UPDRS) total score; secondary endpoints included motor and non-motor subscores, QOL, clinical global impression (CGI) and safety. RESULTS: The study enrolled 485 participants, randomizing 474 (citicoline: 303; placebo: 171). Citicoline significantly increased the likelihood of achieving a minimal clinically important difference compared with placebo (OR 2.06, 95% CI 1.06-3.99; P&#x202f;=&#x202f;0.031) on the MDS-UDPRS total score in the modified intention-to-treat population. Among secondary outcomes, the citicoline group showed greater improvement in motor function (MDS-UPDRS III -2.97 vs -0.13; p&#x202f;=&#x202f;0.009) and a greater improvement on CGI -II and CGI-III (3.26 vs 3.59; p&#x202f;=&#x202f;0.021 and 9.30 vs 10.38; p&#x202f;=&#x202f;0.018, respectively). AEs occurred in 22.1% and 27.1% of the citicoline and placebo groups, respectively. CONCLUSIONS: Citicoline was well tolerated and associated with motor benefits compared with placebo in a highly compliant population. The results suggest a role of citicoline as a safe and possibly effective supportive therapy in PD treated with concomitant dopaminergic agents.

Humans

Using the OPTIMAL Theory to Optimize Aerodynamics in Respiratory Training for Healthy Adults and Individuals With Parkinson's Disease.

BACKGROUND: The OPTIMAL (Optimizing Performance Through Intrinsic Motivation and Attention for Learning) theory is a motor learning framework proposing that optimizing intrinsic motivation enhances motor performance and learning. The theory identifies three key components-Enhanced Expectancies (EE), Autonomy Support (AS) and External Focus of Attention (EF)-which facilitate more efficient, goal-directed movement. These components have been shown to improve motor outcomes in limb-based tasks; however, their application to respiratory training, particularly in clinical contexts such as voice and swallowing therapy in patients with Parkinson's disease (pwPD), has not yet been systematically explored. AIMS: This study aimed to investigate whether implementing OPTIMAL theory strategies during a respiratory muscle strength training (RMST) task improves immediate respiratory motor performance in healthy adults and pwPD. Additionally, we aimed to examine the effects of these strategies on motivation and cognitive engagement. METHODS: This quasi-randomized, single-session trial included 47 participants: Healthy CONTROL (n = 17), Healthy OPTIMAL (n = 16) and PD OPTIMAL (n = 14). Healthy participants were quasi-randomly assigned to either intervention or control conditions, whereas pwPD completed the intervention only. All participants completed a single respiratory session that included baseline, practice and retention phases. Outcome measures included peak expiratory flow, cough peak expiratory flow, cognitive engagement (EEG-based Cognitive Engagement Index) and self-administered motivation questionnaire. OUTCOMES AND RESULTS: Exhalation force improved from baseline to retention in the Healthy OPTIMAL group (baseline: M = 296 L/min; retention: M = 338 L/min; p < 0.001) and the PD OPTIMAL group (baseline: M = 315 L/min; retention: M = 370 L/min; p < 0.0001), but not in the Healthy CONTROL group (p > 0.05). No significant changes in cough strength were observed in any group. No correlations were found between cognitive engagement and exhalation force or motivation scores. However, motivation increased more in the Healthy OPTIMAL group (Questionnaire 1: M = 57.2; Questionnaire 2: M = 60.7) and the PD OPTIMAL group (Questionnaire 1: M = 60.1; Questionnaire 2: M = 62.8) than in the Healthy CONTROL group (Questionnaire 1: M = 61.1; Questionnaire 2: M = 62.5). CONCLUSIONS AND IMPLICATIONS: Implementing the OPTIMAL theory enhances immediate respiratory motor performance in both healthy participants and pwPD. OPTIMAL theory has clinical value in voice and swallowing therapy, although further research is needed to establish long-term efficacy and clinical impact. WHAT THIS PAPER ADDS: What is already known on the subject Motivation is a critical factor in rehabilitation. The OPTIMAL theory has been shown to improve both motivation and motor performance in limb-based tasks. Its impact on respiratory training, however, has not been previously examined. What this paper adds to the existing knowledge This study shows that applying OPTIMAL strategies during a respiratory muscle strength training task significantly improved peak expiratory flow in both healthy adults and people with Parkinson's disease. What are the potential or clinical implications of this work? Integrating the OPTIMAL theory principles into respiratory therapy may enhance motor outcomes, supporting voice, swallowing and cough rehabilitation.

Humans

Importin-8 silencing reduces Ataxin-3 aggregation and alleviates Machado-Joseph disease/spinocerebellar ataxia type 3.

Machado-Joseph disease (MJD) is a polyglutamine neurodegenerative disorder characterized by the formation of neuronal intranuclear Ataxin-3 inclusions. The nucleocytoplasmic transport is known to be profoundly dysregulated from early stages of neurodegeneration, further aggravating its progressive nature. To understand the contribution of these proteins in MJD, we screened the effect of 34 transport proteins on Ataxin-3 aggregation. Importin-8 (Ipo8 gene) was selected for further neuropathology and behavior analysis to evaluate its modulatory effect in vitro and in vivo. Our results showed that Ipo8 mRNA expression is increased in MJD and that, upon Ipo8 downregulation, Ataxin-3 aggregation and neuronal dysfunction are reduced in vitro and in vivo. Furthermore, Ipo8 silencing was demonstrated to alleviate ataxic traits in vivo. Collectively, our findings indicate that Importin-8 may exert its protective effect by modulating NF-kb/p65 and Argonaute-2 proteins, also previously linked to MJD, standing as a promising therapeutic target to delay disease progression.

Argonaute-2

Non-motor symptoms and healthcare utilization before diagnosis of myasthenia gravis: a nationwide cohort study.

BACKGROUND: Non-motor symptoms have been reported prior to myasthenia gravis (MG) diagnosis. However, the temporal patterns of non-motor symptoms and healthcare utilization before MG diagnosis remain unclear. METHODS: We conducted a retrospective, population-based cohort study using the Korean National Health Insurance Service (KNHIS) database from 2011 to 2021. Incident MG cases were identified using the International Classification of Diseases, Tenth and Rare Intractable Disease codes. Individuals younger than 20&#xa0;&#xa0;years or with missing health screening data were excluded. Each MG case was matched 1:10 by age, sex, and index date to controls. Non-motor symptoms and healthcare utilization were defined using operational criteria derived from KNHIS claims data. Rate ratios (RRs) and 95&#xa0;% confidence intervals (CIs) were estimated across four prespecified intervals (0-1, 1-2, 2-5, and 5-10&#xa0;&#xa0;years) before MG diagnosis. RESULTS: We included 8,355 MG patients and 83,550 controls (mean age, 53.7&#xa0;&#xa0;years; male, 44&#xa0;%). MG patients had higher rates of any non-motor symptoms over 10&#xa0;&#xa0;years(RR 1.34; 95&#xa0;% CI 1.30-1.39), with the sharpest increase in the year before diagnosis. Depression, anxiety, migraine, constipation, and insomnia consistently showed higher RRs across all intervals. Hospitalizations (RR 1.66; 95&#xa0;% CI 1.61-1.71) and outpatient clinic visits (RR 1.10; 95&#xa0;% CI 1.04-1.17) were consistently higher across 10&#xa0;&#xa0;years, peaking during the 0-1 year before MG diagnosis. CONCLUSION: Non-motor symptoms and healthcare utilization increased years before MG diagnosis. Earlier recognition of these symptom patterns may facilitate timelier evaluation for MG and improve diagnostic pathways.

Humans

Microglial modulation in general anesthesia: molecular.

General anesthetics profoundly alter brain function and consciousness, yet the mechanisms underlying these effects remain incompletely understood. Although traditional studies have primarily focused on neuronal targets, accumulating evidence suggests that microglia dynamically respond to anesthetic exposure and may participate in anesthesia-associated neurophysiological changes. Beyond their established immune functions, microglia are increasingly implicated in synaptic remodeling, metabolic regulation, neuronal activity surveillance, and neuron-glia communication. Recent studies indicate that different classes of anesthetic agents modulate microglial activity through diverse and context-dependent mechanisms involving inflammatory signaling, purinergic pathways, calcium dynamics, mitochondrial metabolism, and neural circuit interactions. These responses are associated with postoperative neurocognitive disorders, altered synaptic plasticity, and anesthesia-related changes in brain states. In this review, we summarize current evidence regarding the effects of volatile anesthetics, intravenous anesthetics, and analgesics on microglial function and discuss the molecular, functional, and circuit-level mechanisms underlying anesthesia-associated neuron-microglia interactions. We further highlight the dynamic and heterogeneous nature of microglial responses during anesthesia and discuss current limitations in the field, including the lack of temporally resolved and cell-specific approaches. Understanding these processes may provide insights into anesthesia-associated neurocognitive dysfunction and support the development of neuroimmune-targeted strategies in anesthesiology.

General anesthesia

A contextual activity score (CAS) for inferring ADAR-associated transcriptional activity across RNA-seq, single-cell, and spatial transcriptomics.

BACKGROUND AND OBJECTIVE: Adenosine-to-inosine RNA editing, catalyzed by Adenosine Deaminases Acting on RNA (ADARs), is a widespread modification involved in neural function, immune regulation, and cancer. The Alu Editing Index (AEI) is the standard metric to estimate ADAR activity but requires raw sequencing reads and is poorly suited for single-cell and spatial transcriptomic data. This study aimed to develop an alternative framework for inferring ADAR-associated transcriptional activity from gene expression data across diverse transcriptomic technologies. METHODS: We developed the Contextual Activity Score (CAS), a framework based on transcriptional signatures from ADAR perturbation experiments. Context-specific signatures were generated for human neurons, mouse neurons, and cancer models to infer ADAR1 and ADAR2 activity. CAS was computed from normalized gene expression matrices using regulon-based enrichment analysis. Performance was evaluated by comparing with the Alu Editing Index across bulk RNA sequencing datasets, simulated sequencing depths, and library preparation protocols. RESULTS: CAS showed strong concordance with the Alu Editing Index across multiple datasets, while remaining robust to reduced sequencing depth and different library protocols. Unlike the Alu Editing Index, CAS can be applied to single-cell and spatial transcriptomic data and enables the independent assessment of ADAR2 activity. In cancer and neuronal contexts, CAS captured biologically meaningful variations in ADAR-associated transcriptional activity at sample, cell-type, and spatial levels. CONCLUSION: CAS provides a scalable approach applicable across multiple RNA-seq protocols for estimating ADAR-associated transcriptional activity using gene expression data. This method, implemented in an open-source R package for broad adoption, expands the ability to study ADAR-associated transcriptional activity across transcriptomic modalities where direct editing quantification is challenging, such as single-cell and spatial transcriptomics.

Adenosine Deaminase

Transient acoustic stimulation induces time-dependent synaptic remodeling and enhancement of auditory nerve output after threshold recovery.

BACKGROUND: Acoustic stress can alter cochlear function even in the absence of permanent threshold elevation; however, synaptic consequences of transient acoustic stimulation remain incompletely understood. OBJECTIVE: This study aimed to investigate whether transient acoustic stimulation induces changes in the auditory nerve output and cochlear ribbon synapse morphology following hearing threshold recovery. METHODS: Young adult CBA/CaJ mice were exposed to band-limited acoustic stimulation (45-2,000&#xa0;Hz, 95&#xa0;dB SPL, 2&#xa0;h). Auditory brainstem responses (ABRs), hair cell and spiral ganglion neuron survival, and synaptic morphology were evaluated before exposure and up to 2&#xa0;weeks post-exposure. RESULTS: ABR thresholds were transiently elevated immediately after exposure but largely recovered by 1&#xa0;day post-exposure. In contrast, ABR wave I amplitudes significantly increased after threshold recovery across multiple test frequencies. Ribbon-associated puncta in both inner and outer hair cell regions exhibited biphasic temporal changes, with an initial decrease immediately after exposure followed by an increase at 1&#xa0;day post-exposure. The ribbon-associated punctal area also increased after exposure and remained elevated at later post-exposure time points. No significant loss of hair cells or spiral ganglion neurons was observed. Exploratory genomic analysis suggested enrichment of pathways related to metabolic defense and cellular stress responses. CONCLUSIONS: Transient acoustic stimulation induces time-dependent synaptic remodeling and enhancement of peripheral auditory nerve output without overt cellular degeneration. These findings support a model in which early cochlear responses to acoustic perturbation include adaptive synaptic plasticity and gain regulation, extending current concepts of noise-induced cochlear change beyond irreversible synaptic loss.

Animals

Diagnostic and Predictive Value of Circulating and Exosomal microRNAs in Ferroptosis-Associated Neurological Conditions: A Systematic Review and Meta-analysis.

Circulating microRNAs (miRNAs) have emerged as potential non-invasive markers for intracranial pathology, yet their diagnostic accuracy and relationship with ferroptosis-mediated neuronal damage remain poorly defined. The primary objective of this study was to evaluate the diagnostic and predictive potential of circulating and exosomal miRNAs across ferroptosis-associated neurological conditions and to explore their associations with ferroptosis-related pathways. Following PRISMA-DTA guidelines, a systematic literature search was conducted across PubMed, Scopus, Cochrane, and ScienceDirect, identifying 205 records. After screening for human clinical cohort validation, 7 studies were included in the qualitative synthesis and 5 in the quantitative meta-analysis. Pooled Area-under-the-Curve (AUC) was calculated using a random-effects inverse-variance model, while prognostic correlation coefficients (r) were synthesized using Fisher's Z-transformation. Methodological quality was assessed via QUADAS-2. Analysis of 7 clinical cohorts provided heterogeneous evidence on the diagnostic and prognostic potential of miRNAs. Random-effects pooling of the two eligible diagnostic AUC estimates yielded an exploratory pooled AUC of 0.87 (95% CI, 0.79-0.94; I2&#x2009;.90%). Prognostic synthesis of Group 2 identified an exploratory association between miRNA levels and clinical severity scales (exploratory pooled correlation coefficient of 0.67 (95% CI: 0.56-0.76; I2&#x2009;.714.4%). Selected miRNAs were mapped to ferroptosis-associated regulators, including SLC7A11, ABCB8, and SLC40A1. Exosomal miRNAs hold potential to indicate disease-associated molecular information, although comparative clinical evidence remains yet to be explored. Circulating and exosomal miRNAs show promising diagnostic and prognostic potential across selected neurological conditions. These findings highlight a potential mechanistic association between miRNA expression and ferroptosis-mediated neuronal injury.

Humans

Short-term psychodynamic psychotherapy for functional neurological disorder: A pilot randomized controlled trial.

BACKGROUND: Evidence-based psychotherapeutic treatments for Functional Neurological Disorder (FND) remain limited. This pilot trial evaluated the preliminary efficacy of Short-term Psychodynamic Psychotherapy (STPP) plus Standard Medical Care (SMC) compared with SMC alone in reducing FND symptom frequency. METHODS: Adults with FND were randomized (1:1) to receive either SMC alone or 12 weekly sessions of STPP plus SMC. The primary outcome was symptom frequency (days with symptoms in the last 4 weeks) assessed at the end of treatment (3 months) and at 6-month follow-up. Secondary outcomes included treatment response (&#x2265;50% reduction in symptom frequency) and scores on the Hamilton Depression Rating Scale (HAM-D), Hamilton Anxiety Rating Scale (HAM-A), and World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0). RESULTS: Of 91 randomized patients (mean age 38.2 years, 75.8% female), 81.3% completed follow-up. Intention-to-treat analysis using Linear Mixed Models showed that STPP plus SMC significantly reduced symptom frequency compared with SMC alone (estimated mean difference -5.72 [95% CI -8.68 to -2.77]; Cohen's d = 0.77; p&#x202f;<&#x202f;0.001).Treatment response was achieved by 65.8% in the intervention group versus 16.7% in controls (OR 8.21 [95% CI 2.79-24.19]; p&#x202f;<&#x202f;0.001; NNT 2.0).Significant improvements were also observed for depression (HAM-D: estimated mean difference -10.80; d = 1.45), anxiety (HAM-A: -7.94; d = 1.06), and disability (WHODAS 2.0: -5.77; d = 0.74), all p&#x202f;<&#x202f;0.001. CONCLUSIONS: STPP was associated with clinically meaningful improvements in FND symptom frequency and all secondary outcomes, with large effect sizes and high treatment response rates. These findings support the preliminary efficacy of STPP for FND and justify larger, multicenter confirmatory trials.

Humans

A systematic review and meta-analysis of visuospatial attentional deficits in Parkinson's patients.

Parkinson's disease (PD) is a neurodegenerative condition primarily characterized by motor deficits, yet cognitive impairments are increasingly recognized. While deficits in executive functioning are well documented even in the absence of cognitive decline, evidence of attentional deficits in PD remains inconsistent, and the role of motor symptom lateralization is unclear. In this systematic review and meta-analysis, we examined visual attention in right-handed, cognitively unimpaired idiopathic PD patients, focusing on the canonical attentional domains (sustained, selective, divided) and processes (alerting, endogenous and exogenous orienting, reorienting), as well as visuospatial bias. Four databases were searched for studies comparing PD patients with healthy controls. Meta-analytic estimates were derived using Hedges' g within random-effects models, and studies that could not be quantitatively integrated were summarized narratively. In addition, studies directly comparing patients with left- and right-predominant motor symptoms (LPD vs. RPD) were reviewed qualitatively. Across 51 studies, PD patients exhibited deficits in sustained, selective, and divided attention. Among attentional processes, only exogenous orienting was impaired, whereas alerting, endogenous orienting, and reorienting were preserved. Findings from the few studies examining visuospatial bias indicated small, context-dependent shifts in spatial attention rather than a consistent directional bias. These findings indicate that PD patients show visual-attentional impairments, particularly under high-demand conditions, while basic alertness and voluntary orienting appear preserved. Exogenous orienting deficits and subtle rightward spatial tendencies in LPD suggest disruption of right-hemisphere attentional networks. These results have implications for early cognitive assessment, rehabilitation strategies, and understanding the neural bases of attentional dysfunction in PD.

Humans

Effects of anodal transcranial direct current stimulation over the right primary motor cortex on a sequential motor finger tapping task in developmental stuttering.

INTRODUCTION: This study investigates the impact of anodal transcranial direct current stimulation (tDCS) on non-speech sequential motor practice in adults who stutter (AWS), compared to non-stuttering controls (ANS). Recent research has explored the effects of tDCS on speech fluency in stuttering. However, its effect on non-speech motor tasks has not yet been studied. METHODS: 20 AWS and 30 ANS right-handed participants were randomly assigned to anodal or sham tDCS conditions, performing a sequential finger tapping task. We targeted over the right primary motor cortex, stimulating at 2&#x202f;mA for 20&#x202f;min. Sequence duration and reaction time were analyzed. RESULTS: AWS analysis revealed that the anodal condition had significantly slower reaction times in the second half of the task compared to sham. For sequence durations, AWS in the anodal condition had slower overall sequence durations than the sham condition. However, there were no block-by-block differences in sequence duration. When comparing AWS and ANS, no significant differences were observed for sequence duration. However, there were significant differences in reaction time between AWS and ANS, specifically in earlier blocks. Additionally, there was no significant Group &#xd7;&#x202f;Condition interaction. DISCUSSION: The findings suggest that anodal stimulation impeded finger sequencing in AWS, showing overall slower sequence durations and a diminishing effect on reaction times in the second half of the experiment, suggesting anodal tDCS may interact uniquely with the neural mechanisms in stuttering. Future studies should explore the effects of anodal tDCS on non-speech motor tasks to gain a broader understanding of its impact on motor control and motor learning.

Humans

Response-optimised training improves learning of a complex motor task and closely related motor tasks.

Regular physical exercise is essential for promoting healthy aging and longevity. In older adults with varying physical and cognitive decline, optimising exercise interventions is crucial to maximise benefits. A promising approach to achieve this goal is by adjusting task demands to individual abilities in turn preventing over- or underloading their abilities. In the field of motor learning, it is currently unclear whether such an optimised training improves not only performance on the trained task but also transfers to untrained motor and cognitive tasks. We conducted a randomized, single-blinded, 6-week dynamic balance training (DBT) with healthy older adults (n&#xa0;=&#xa0;30). Training was tailored to individual balance ability. Participants were assigned to either suboptimal (high or low difficulty) or optimal (moderate difficulty) training groups. Transfer effects were assessed via cognitive tasks (memory and executive) and motor tasks (untrained DBT variations and other balance tasks) measured pre-, mid- and post-intervention. Multivariate longitudinal statistical analysis showed higher performance gains in the optimal training group in three out of six sessions compared to the suboptimal groups, especially under testing conditions with high task demands. The optimal group also showed greater improvements in near motor transfer tasks mid- and post-intervention, while no significant differences were observed in the cognitive tasks. Within-group DBT learning positively correlated with transfer gains, highlighting the role of training response in achieving transfer. In conclusion, optimised task difficulty in balance training enhances both task-specific performance and related motor skills, supporting the use of personalised interventions to maintain function and independence in older adults.

Humans

Multi-centre randomised controlled feasibility trial with embedded process evaluation of a samba percussion intervention for people living with Parkinson's disease: a protocol for the Sparky Samba trial.

INTRODUCTION: Parkinson's disease (PD) is the second most common neurodegenerative disorder, its principal symptom being deterioration of motor function. Current treatment options are limited to symptom management but there is evidence that physical activity can provide motor benefits. More recently there is evidence to suggest that rhythmic auditory stimulation may improve gait and balance in PD. Sparky Samba is a community initiative in South Wales, UK, founded by a person living with PD. Sessions incorporate the following samba rhythms from a trained facilitator and are held weekly in a community setting. METHODS: The Sparky Samba trial is a multi-site, non-blinded, randomised controlled feasibility trial of Sparky Samba compared with activity as usual. A total of 60 people with PD will be randomised 1:1 to take part in a local Sparky Samba group for 12 weeks or continue their normal activities for the same length of time. The primary outcome is feasibility defined by recruitment, retention, data completeness and intervention adherence. Secondary outcomes relating to motor function, cognition, well-being and self-efficacy will also be assessed at baseline and at 12 weeks. Additionally, we will conduct a process evaluation to understand contextual mechanisms surrounding Sparky Samba. This will be achieved through qualitative interviews and structured participant questionnaires following individual trial completion and through structured questionnaires with intervention delivery staff, supplemented with qualitative interviews. ANALYSIS: Feasibility outcomes will be assessed according to pre-defined criteria. For secondary outcomes, means and standard deviations (or medians and IQRs) will be calculated by arm, alongside 95% CIs for change from baseline to 12-week follow-up. Qualitative data will be subject to thematic analysis using NVivo software. ETHICS AND DISSEMINATION: This study received a favourable ethical opinion from the North of Scotland Research Ethics Committee in April 2025 (REC reference 25/NS/0037). Study results will be disseminated through the peer-review literature, the ISRCTN registry and directly to participants, which will be facilitated by the study's public and patient involvement steering group. TRIAL REGISTRATION NUMBER: ISRCTN11861663.

Humans

High-frequency contralesional dorsal premotor cortex and low-frequency contralesional primary motor cortex rTMS in subacute stroke with severe upper limb impairment: comparable motor outcomes and differential regional degree centrality changes.

BACKGROUND: The contralesional dorsal premotor cortex has been proposed as a potential neuromodulatory target for patients with severe upper limb impairment due to subacute ischemic stroke. This proof-of-concept study aimed to compare behavioral outcomes and resting-state neuroimaging findings between high-frequency repetitive transcranial magnetic stimulation (rTMS) over the contralesional dorsal premotor cortex and guideline-supported low-frequency stimulation over the contralesional primary motor cortex. METHODS: In this randomized trial, 46 patients with severe upper limb impairment in the subacute stage after ischemic stroke were randomly assigned to receive either high-frequency rTMS over the contralesional dorsal premotor cortex or low-frequency rTMS over the contralesional primary motor cortex. Low-frequency stimulation over the contralesional primary motor cortex served as an evidence-supported active comparator for poststroke upper limb motor recovery. Stimulation was administered five times per week for two weeks using magnetic resonance imaging-guided neuronavigation. All participants received concurrent standard rehabilitation therapy. The primary outcome was the Fugl-Meyer Assessment for Upper Extremity. Secondary outcomes included the Arm Subscore of the Motricity Index, the Hong Kong version of the Functional Test for the Hemiplegic Upper Extremity, the Modified Barthel Index, and resting-state functional magnetic resonance imaging-derived degree centrality. RESULTS: Both groups showed significant improvements in the primary and secondary behavioral measures (p&#x202f;<&#x202f;0.01), with no significant between-group differences in the magnitude of change (p&#x202f;>&#x202f;0.05). In neuroimaging analyses, patients receiving high-frequency rTMS over the contralesional dorsal premotor cortex showed significantly greater degree centrality changes in the ipsilesional middle occipital gyrus, contralesional medial superior frontal gyrus, and contralesional middle frontal gyrus than those receiving low-frequency rTMS over the contralesional primary motor cortex (p&#x202f;<&#x202f;0.05). Within the high-frequency stimulation group, degree centrality changes in the ipsilesional middle occipital gyrus were positively correlated with improvements in the Fugl-Meyer Assessment for Upper Extremity (r&#x202f;=&#x202f;0.619, false discovery rate-corrected p&#x202f;=&#x202f;0.018). CONCLUSIONS: High-frequency rTMS over the contralesional dorsal premotor cortex produced behavioral improvements comparable to guideline-supported low-frequency rTMS over the contralesional primary motor cortex, without establishing superiority or formal non-inferiority. Exploratory neuroimaging analyses showed greater degree centrality changes in the ipsilesional middle occipital gyrus after high-frequency premotor stimulation, and these changes correlated with upper-limb motor improvement. These findings support further investigation of contralesional dorsal premotor cortex-targeted high-frequency rTMS for severe subacute post-stroke upper limb impairment. REGISTRATION: URL: http://www.chictr.org.cn; Unique identifier: ChiCTR2000038049.

Humans