Search Results (781)

Recent advances in robotics have highlighted the importance of multimodal perception for dexterous manipulation in contact-rich environments. Here we present BiTAT, a bimanual tactile-augmented teleoperation system for collecting multimodal human demonstrations and learning manipulation policies. The system integrates custom capacitive tactile sensors into parallel grippers and displays the resulting contact-deformation images to the operator. We evaluated the system in four controlled laboratory tasks: USB removal/insertion, bottle cap unscrewing, cucumber peeling, and toothpaste squeezing. In a pilot repeated-measures study with eight laboratory participants, visual tactile feedback was associated with success-rate increases of 12.5–32.5 percentage points and shorter completion times among successful trials. We further propose a multimodal Diffusion Policy that fuses visual, tactile, and proprioceptive features through a Transformer encoder. In two fixed-layout autonomous tasks, the complete model achieved higher observed success rates than the vision-only baseline, including a 45-percentage-point difference in the 50-demonstration toothpaste-squeezing setting. Together, these results demonstrate the feasibility of the proposed hardware–policy pipeline and suggest that tactile augmentation benefits both human teleoperation and learned manipulation policies in contact-rich tasks. Full article

Botulinum neurotoxin type A (BoNT-A) is used across coexisting craniocervical conditions, and therapeutic response is often overinterpreted as evidence of a shared generator. The bruxism literature shows why. Across six controlled studies with event-level outcome measurement, reported effects on event frequency track not dose or injection field but whether the rule used to detect an event could follow the amplitude the toxin had just reduced; none yet combines a placebo arm with an amplitude-independent event definition. This targeted critical narrative review interprets representative evidence mechanistically rather than assessing efficacy. It examines chronic migraine, tension-type headache, myogenous temporomandibular disorders, and bruxism, with somatosensory tinnitus as a cross-modal boundary case. Efficacy is protocol-specific in chronic migraine and uncertain elsewhere. Tracing studies locate somatosensory routes to the cochlear nucleus in the spinal trigeminal and dorsal column nuclei; a direct mesencephalic-trigeminal-to-cochlear projection has not been demonstrated in the tracing literature reviewed, so somatic–auditory plausibility does not establish the masticatory proprioceptive route invoked by muscle-targeted rationales. Because BoNT-A affects motor output, peripheral nociceptive signaling, and muscle spindle input—the last of these probably differing in availability across injection fields—we frame it as a site-dependent, multi-output perturbation. That pharmacology is established; what is offered here is the inferential framing and the anatomical constraint following from it. Full article

High-velocity baseball pitches place demands on the shoulder, requiring precise sensorimotor control to maintain joint stability and consistent throwing mechanics. Immersive virtual reality (IVR) has emerged as a platform for sensorimotor training, offering controlled, interactive environments, although its immediate effects on shoulder joint position sense remain unknown in overhead athletes. This preliminary within-subject pilot study evaluated whether a brief IVR-based closed kinetic chain (CKC) task using the ICAROS Lightning device could acutely improve active joint position sense (AJPS) in the dominant arm of collegiate baseball players. Nine male collegiate baseball athletes completed baseline AJPS testing during shoulder internal and external rotation before a 2-min immersive flight simulation task, then repeated AJPS assessment. Absolute angular error was the primary outcome. Following the intervention, AJPS error was significantly reduced in both rotational directions. Mean internal rotation error decreased by 4.22° (95% CI: 3.02° to 5.42°; p < 0.001; Cohen’s dz = 2.70), while mean external rotation error decreased by 4.73° (95% CI: 3.10° to 6.37°; p < 0.001; Cohen’s dz = 2.23). These preliminary findings suggest IVR-based CKC exercise acutely improves shoulder joint position sense, which may have implications for restoring proprioception following throwing-induced fatigue. Further validation is warranted in randomized controlled studies with larger, heterogeneous samples in order to determine whether these findings have meaningful effects on throwing performance or recovery. Full article

Background: Physical activity is widely recommended for preserving musculoskeletal health and managing osteoarthritis-related pain, although its benefits are commonly framed in terms of muscle strengthening, weight control, and physical performance. This narrative review aimed to examine movement more broadly as a physiological regulator of synovial joint homeostasis, sensory calibration, and functional adaptation. Methods: A structured literature search was performed in PubMed/MEDLINE, Scopus, and Web of Science from database inception to 1 February 2026. Experimental studies, observational studies, clinical trials, systematic reviews, meta-analyses, and selected narrative reviews addressing movement-responsive joint biology or pain regulation were considered. Evidence was synthesized across four interrelated domains: mechanical, fluidic, immune-metabolic, and sensory regulation. Results: The narrative synthesis indicates that the concept of the synovial joint as a dynamic mechano-fluidic organ in which cartilage, synovium, synovial fluid, capsule, subchondral bone, periarticular tissues, and sensory pathways interact continuously. Repeated physiological movement may promote synovial fluid exchange, lubrication, cartilage nutrition, hyaluronic acid and lubricin function, matrix turnover, anti-inflammatory signaling, proprioceptive control, and exercise-induced hypoalgesia. In contrast, inactivity and unloading may impair fluid dynamics, promote muscle inhibition, stiffness, inflammatory persistence, sensory deconditioning, and loss of function. Excessive or poorly distributed loading may also disrupt homeostasis through matrix injury, inflammation, fatigue, and nociceptive sensitization. These findings informed the proposed adaptive loading window, a hypothesis-generating conceptual framework rather than a clinically validated threshold, describing the dynamic range of movement within which joint function and pain regulation may be supported without sustained tissue or symptom aggravation. Conclusions: Movement should be viewed not only as a therapeutic intervention, but also as a continuous regulator of joint biology and perception. Its clinical value may depend on identifying an individualized loading range that supports adaptation, function, and confidence in movement while avoiding both underloading and overload. Full article

Peripheral vestibulopathy (PV) is a common disorder that causes dizziness and balance impairment, substantially affecting patients’ quality of life. When symptoms persist, they frequently lead to anxiety, depression, and an increased risk of social isolation. Although central vestibular compensation (CVC) often promotes functional recovery, current pharmacological options remain limited and are primarily aimed at symptom control. Consequently, they should be considered adjuncts rather than alternatives to rehabilitation-based strategies. Vestibular rehabilitation (VR) remains the cornerstone of treatment for promoting functional recovery in patients with PV. Based on the complementary mechanisms of adaptation, substitution, and habituation, VR enhances the central nervous system’s ability to compensate for vestibular deficits by optimizing the integration of visual, proprioceptive, and residual vestibular inputs. Robust evidence from both clinical and preclinical studies has demonstrated its efficacy in improving postural stability, dynamic balance, gaze stabilization, and overall functional performance. Experimental studies using animal models have further highlighted the critical role of active sensorimotor training in ecologically relevant environments for enhancing vestibular compensation. Pharmacological interventions may further facilitate these adaptive processes by modulating the neurobiological mechanisms underlying vestibular compensation, thereby improving responsiveness to rehabilitation. Likewise, emerging neuromodulation approaches, including galvanic vestibular stimulation, have shown promising potential to enhance neural plasticity and augment the effects of rehabilitation. Consequently, combining VR with targeted pharmacological therapies and/or vestibular stimulation techniques may provide synergistic benefits and maximize functional recovery. In conclusion, vestibular rehabilitation should remain the foundation of PV management and be integrated with pharmacological and neuromodulatory approaches within a multidisciplinary therapeutic framework. Further research is needed to optimize rehabilitation protocols, identify the biological determinants of successful vestibular compensation, and develop personalized therapeutic strategies aimed at maximizing functional recovery and improving patients’ quality of life. Full article

Background/Objectives: Inclusion body myositis (IBM) causes progressive, quadriceps-predominant weakness that impairs mobility and increases fall risk, yet outcomes most relevant to independence remain unsynthesized for IBM. This review compiles direct IBM evidence across five domains (A1–A5): natural history, motor performance, falls and balance, sensory/peripheral-nerve function, and interventions. Methods: Eight databases and two trial registers were searched without date or language limits. Eligible studies enrolled adults with IBM based on recognized criteria reporting lower-limb strength or function, gait, transitional tasks, balance, falls, or intervention outcomes; mixed-myopathy cohorts required extractable IBM-specific data. Two reviewers independently screened, extracted, and appraised risk of bias, following PRISMA 2020. Results: Sixty-four studies were included; per-domain totals (A1: 16, A2: 9, A3: 6, A4: 2, and A5: 38) exceed 64 because studies may span domains. Quadriceps strength was the most sensitive progression marker, detected earlier by quantitative testing. Falls were near-universal and insufficiently managed. No drug showed convincing functional benefit in controlled trials, whereas exercise and orthotic/robotic assistance appeared to be safe in small studies. Sensory and peripheral-nerve dysfunction were common, but proprioceptive acuity and postural balance were unmeasured. Conclusions: IBM progression is best measured by quantitative quadriceps strength and function. Intervention evidence derives largely from small, uncontrolled and neutral trials. Primary myopathy is likely the principal driver of decline, but its downstream consequences—for balance, proprioception, and falls—remain underexplored and are the priority for future study. Full article

Background/Objectives: Walking-induced fatigue disrupts postural balance, but the differentiated effects of walking uphill and downhill remain unclear. The aim was to compare the impact of two walking sequences, either uphill (+10%) or downhill (−20%), with an identical number of steps (7000 steps) on a treadmill at 5.5 km·h⁻¹ on postural balance. Methods: Nineteen healthy young participants performed the two walking sequence sessions (56 and 57 min) eight days apart. Eyes-closed bipedal postural balance (in three randomized conditions: an unmanipulated condition, a tendon vibration manipulation condition—TV—and a galvanic vestibular stimulation manipulation condition—GVS), maximal voluntary contraction and central activation ratio were assessed before (PRE), immediately after (POST) and 20 min after (POST20) each walking sequence. Results: Walking uphill and walking downhill sequences generated similar muscular and central fatigue in the POST and POST20 conditions. In the unmanipulated postural condition, postural balance was disrupted after both walking sequences in the POST condition, with no difference between walking downhill and walking uphill. In the manipulated postural conditions, postural balance was modified by the walking sequences. It was disrupted in the presence of GVS in the POST condition with no difference between walking downhill and uphill, whereas it was not disrupted in the presence of TV and was even improved after walking uphill. Conclusions: Although the postural alteration was broadly similar between the two walking sequences, their disruptive factors would differ at the muscular, metabolic and sensory levels. Full article

Unmanned surface vehicle (USV) formations operating under GNSS denial require accurate relative localization using proprioceptive sensors and inter-vehicle ranging. This paper presents an anomaly-aware adaptive extended Kalman filter for four-USV formations using inertial measurements, compass, and ultra-wideband ranging, and systematically characterizes its operating envelope. Observability analysis establishes that S-curve maneuvering achieves structural rank 24, with only global translation unobservable, while straight-line motion leads to a rank deficiency of exactly seven dimensions All four gyroscope biases remain observable under both trajectories. The proposed filter integrates chi-square testing, cumulative sum (CUSUM) detection, and bias drift rate monitoring to trigger coordinated R adaptation and Q-boost mechanisms. Controlled experiments spanning outlier magnitudes and drift rates reveal three performance regimes, clean conditions with equivalent performance across all variants, moderate outliers $[3{\sigma }_d,10{\sigma }_d]$ where the proposed method achieves 4.8–13.4% improvement, and extreme outliers where all robust methods converge. Critically, pure bias drift experiments expose a structural limitation of single-hypothesis, residual domain robustification within the tested drift range—all variants exhibit equivalent performance across the tested drift rates, analytically attributable to Kalman gain partitioning that distributes innovations between position and bias subspaces. The characterized operating envelope establishes that robust mechanisms provide measurable benefits for transient anomalies but encounter hard boundaries under persistent drift conditions, with all variants converging to equivalent performance across the tested range, necessitating multi-hypothesis or constraint-based approaches. Full article

Background: Mechanosensitive ion channels PIEZO1 and PIEZO2 are key mediators of mechanotransduction, which converts physical forces into cellular signals involved in proprioception, touch, vascular function, and other physiological processes. Mutations in human PIEZO proteins are linked to various diseases, such as hereditary xerocytosis, lymphatic dysplasia, and proprioceptive dysfunction. However, the role of intrinsic disorder in the regulation of these proteins and their susceptibility for disease-associated mutations remains unclear. Methods: We analyzed canonical human PIEZO1 and PIEZO2 protein sequences using machine learning, neural network, and energy-based disorder predictors, together with the prediction of disorder-mediated binding regions, phase separation propensity, interaction networks, evolutionary conservation, clinically annotated human variants, and peptide structural modeling. Results: Both proteins showed moderate intrinsic disorder, with PIEZO2 having slightly greater disorder propensity and higher predicted phase separation potential. Intrinsically disordered regions frequently overlapped binding-prone segments and post-translational modification sites, supporting regulatory functions. Evolutionary comparisons showed strong conservation of PIEZO proteins, while selected disordered regions retained disorder propensity despite greater sequence variability. Disease-causing variants mainly affected the ordered regions of both proteins, whereas disordered regions contained proportionally more benign variants and relatively few pathogenic mutations. The modeling of mutations within disordered hotspots showed altered local conformational tendencies, indicating that some disease variants may disrupt dynamic interaction interfaces rather than global structure. Interaction network analysis linked both proteins to enriched mechanotransduction, ion transport, and cytoskeletal pathways. Conclusions: Overall, our findings identify intrinsic disorder as an underappreciated feature of PIEZO channel biology and provide a framework for interpreting PIEZO-associated channelopathies. PIEZO proteins also perfectly illustrate the proteoform concept, where one gene yields a highly diverse kit of mechanosensitive molecular tools. While humans only have two primary PIEZO genes (PIEZO1 and PIEZO2), the body generates a vast array of functional variations. Full article

Alzheimer’s disease is biologically defined by beta-amyloid and tau pathology, yet the mechanisms through which molecular and network alterations become expressed as the progressive loss of meaningful behaviour remain incompletely understood. This perspective proposes a neurocognitive framework in which apraxia provides a particularly informative clinical window onto the deterioration of functional integration. The model assigns a central organisational role to interhemispheric communication within distributed frontoparietal, temporal, language, memory, and default mode networks. It interprets recognised apraxic syndromes as clinically distinct disturbances that expose complementary requirements of meaningful action, including action knowledge, bodily configuration, sequencing, spatial organisation, object use, fine motor control, and interhemispheric transfer. The framework further examines whether partially convergent impairments of gesture, connected speech, autobiographical construction, and perspective coordination may reflect declining capacity to integrate specialised representations within coherent behaviour. Its original theoretical component proposes that conscious proprioceptive organisation contributes to maintaining body-centred reference frames through which heterogeneous information is coordinated during action and perspective transformation. Evidence for Alzheimer-related connectivity alterations and impairments of praxis, discourse, and autobiographical memory is reviewed separately from the proposed integrative mechanism, which requires direct testing. The framework predicts that longitudinal changes across these behavioural domains will covary with deterioration in interhemispheric and large-scale network connectivity and provide explanatory information beyond global cognitive severity and regional atrophy. Multimodal longitudinal studies combining molecular biomarkers, neuroimaging, apraxia assessment, connected-speech analysis, and autobiographical tasks are proposed to evaluate, delimit, or reject these predictions. Full article

Adaptive locomotion across continuous terrain transitions remains difficult for hexapod robots because contact timing, body attitude, support height, and load distribution change simultaneously along a route. This paper presents a unified proprioception-driven deep reinforcement learning and central pattern generator (DRL-CPG) framework for terrain-transition locomotion without visual terrain classification, explicit terrain labels, or terrain-specific controller switching. A high-level proximal policy optimization policy maps a 46-dimensional proprioceptive observation to a three-dimensional CPG modulation action comprising oscillation amplitude, swing-phase frequency, and turn modulation. A coupled six-node Hopf oscillator network then expands these modulated parameters into phase-coordinated rhythmic commands, which are mapped to the 18 joint targets of a JetHexa hexapod and executed by a low-level proportional-derivative controller. The observation space contains body linear velocity, body angular velocity, relative joint positions, relative joint velocities, the previous three-dimensional policy action, and inertial measurement unit (IMU)yaw/heading relative to the initial track direction. A continuous route consisting of flat ground, uphill stairs, irregular terrain, downhill stairs, and a recovery segment is defined to evaluate transition-aware locomotion using route completion, velocity-tracking error, lateral deviation, and roll/pitch fluctuation. Compared with the fixed-parameter CPG and end-to-end DRL baselines, the proposed method increased the full-distance success rate at 4.7 m from 9% and 20%, respectively, to 88%, while maintaining smoother velocity, lateral deviation, and roll/pitch responses. The framework preserves the rhythmic prior of CPG control while reducing the exploration burden of reinforcement learning, providing a compact formulation for adaptive hexapod locomotion across terrain transitions. Full article

Temporomandibular disorders (TMD) comprise a heterogeneous group of pain and dysfunction conditions involving the temporomandibular joint, masticatory muscles, and related structures. Although occlusal interference has long been discussed in relation to TMD, current evidence does not support an occlusion-centered etiological model for most patients. Within the contemporary biopsychosocial framework embodied by the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD), occlusal interference is better regarded as one of several potential peripheral biomechanical inputs that may interact with individual pain susceptibility, parafunctional loading, inflammatory status, and psychosocial factors. This review synthesizes evidence on how peripheral biomechanical and inflammatory inputs may engage masticatory muscle–nerve signaling, trigeminal nociceptor activation, and neurogenic inflammation. We discuss altered masticatory muscle activity, proprioceptive and nociceptive afferent signaling, neuropeptide release, neurovascular and mast cell–nerve interactions, and glial activation within trigeminal pain pathways. Molecular mechanisms, including TRP channel and P2X3 receptor activation, voltage-gated ion channel dysregulation, MAPK, PI3K/Akt/mTOR, cAMP/PKA/CREB signaling, and epigenetic regulation, are reviewed as candidate pathways linking peripheral input to pain-related plasticity. These mechanisms are further considered in relation to hyperalgesia, mechanical allodynia, pain memory, emotional and cognitive modulation, and sex-related differences in pain processing. Finally, we evaluate translational implications, including mechanism-oriented animal models, exploratory biomarkers, human-derived experimental systems, and mechanism-informed interventions, while emphasizing their current limitations. Overall, this review proposes a cautious mechanistic framework in which peripheral inputs may contribute to TMD-related pain amplification in selected contexts, but clinical translation requires validated phenotyping, longitudinal evidence, and integration with conservative, reversible, and patient-centered standard-of-care management. Full article

Background/Objectives. Spinal misalignment in childhood and adolescence may be associated with altered sensory integration and body representation. The subjective visual vertical reflects visual, vestibular, and somatosensory integration, but its relationship with pediatric spinal misalignment remains uncertain. This study investigated the subjective visual vertical using two complementary paradigms. Methods. This exploratory, single-center, cross-sectional study included participants aged 7–17 years with clinically identified spinal misalignment. Participants underwent standardized physiatric assessment and subjective visual vertical testing using a luminous-line test and the Bucket Test. Spearman’s rank correlations examined associations with clinical and radiographic variables, with false-discovery-rate control using the Benjamini–Hochberg procedure. Radiographic analyses were restricted to participants with available imaging. Results. Fifty-seven participants were included (mean age 12.8 years, SD 2.25), and all completed both tests. Mean subjective visual vertical was 0.053° (SD 0.953) with the luminous-line test and −0.561° (SD 1.165) with the Bucket Test. Radiographs were available for 21 participants. No association remained significant after false-discovery-rate correction. Two luminous-line associations were nominally significant before correction: primary lumbar curve presence (ρ = −0.278, p = 0.036) and secondary thoracolumbar curve presence (ρ = −0.324, p = 0.015); both had q = 0.721. The tests were moderately correlated (ρ = 0.493, p < 0.001). Radiographic sensitivity and subgroup analyses showed no significant findings. Conclusions. Subjective visual vertical was not robustly associated with spinal misalignment characteristics in this modest, clinically heterogeneous cohort. Larger controlled studies with standardized imaging and adequately powered severity groups are required. Full article

Accurate and robust localization remains the fundamental bottleneck for truly autonomous robotic systems, despite decades of progress in probabilistic estimation and SLAM. This paper provides a critical and comprehensive review of mobile robot localization across sensing modalities, estimation paradigms, and deployment domains, covering ground, aerial, and underwater platforms. Beyond a descriptive survey, we explicitly analyze the limitations and trade-offs of existing approaches. We introduce an updated taxonomy that spans classical proprioceptive and exteroceptive sensors, emerging technologies such as 4D imaging radar and event cameras, and infrastructure-based positioning systems including GNSS and Ultra-Wideband. We revisit the evolution of localization algorithms, from Bayesian filtering techniques (EKF, UKF, and particle filters) to modern graph-based SLAM frameworks and tightly coupled multi-sensor fusion systems. Particular emphasis is placed on the recent paradigm shift toward learning-based and neural implicit approaches, including NeRF-SLAM and Gaussian Splatting, highlighting both their transformative potential and their current impracticality for real-time deployment. Unlike previous surveys, this work provides a unified cross-domain perspective while critically examining scalability, robustness, computational cost, and real-world deployability. We identify key unresolved challenges, including long-term consistency, operation in degraded environments, and the integration of semantic understanding into localization pipelines. Furthermore, we propose standardizing evaluation metrics with a formal Trajectory Completeness formulation to expose tracking brittleness. Finally, we outline future research directions toward resilient, certifiable, and truly autonomous localization systems, emphasizing the critical transition from passive estimation to Active SLAM in unstructured environments. Full article

Objective: This study comprehensively compared the acute effects of active stretching (AC), passive stretching (PA), proprioceptive neuromuscular facilitation (PNF), and dynamic stretching (DS) on lower-limb muscle stiffness and range of motion (ROM). Methods: A randomized crossover repeated-measures design was employed. Data were acquired using MyotonPRO (Myoton AS, Tallinn, Estonia, Software v.5.0.0.257). Twelve physically active male college students participated in the study. Each participant completed all five conditions (CO, AC, PA, PNF, DS) in a randomized order, separated by 48 h washout periods. Muscle stiffness and ROM of the lower-limbs were evaluated before and after each stretching intervention. Muscle stiffness was measured in the following muscles (L = left; R = right): quadriceps: vastus lateralis (Vlt), rectus femoris (RF), vastus medialis (Vm); hamstrings: semitendinosus (Sem), biceps femoris (Bic); gluteus maximus (GM); gastrocnemius: medial (Gcm)/lateral (Gclt). A two-factor repeated-measures analysis of variance (ANOVA) with Bonferroni correction was employed to examine ROM and muscle stiffness under different stretching methods. Results: 1. All methods improved ROM (PA 95% CI [2.15, 4.66], η² = 0.35; PNF 95% CI [1.80, 4.32], η² = 0.30; AC 95% CI [1.92, 4.43], η² = 0.32; DS 95% CI [3.50, 6.01], η² = 0.51; p < 0.05); 2. PA significantly reduced muscle stiffness in Gcm-L (95% CI [−28.00, −8.74], η² = 0.210), Gclt-L (95% CI [−16.52, −2.18], η² = 0.110)/R (95% CI [−32.75, −8.10], η² = 0.167), and Vm-L (95% CI [−15.73, −6.33], η² = 0.079), but increased RF-L (95% CI [6.16, 21.58], η² = 0.191) stiffness; PNF significantly increased Sem-L (95% CI [2.46, 16.51], η² = 0.117) and Vm-R (95% CI [4.83, 16.21], η² = 0.200) stiffness; AC significantly reduced Sem-R (95% CI [−20.59, −0.83], η² = 0.079) stiffness while increasing GM-R (95% CI [6.34, 17.29], η² = 0.254) stiffness; DS significantly decreased muscle stiffness in Vlt-L (95% CI [−21.23, −5.90], η² = 0.186) and Sem-R (95% CI [−23.09, −3.33], η² = 0.115) (p < 0.05). Conclusions: DS significantly improved lower limb flexibility and reduced muscle stiffness in selected muscles. AC improved anterior thigh muscle stiffness. PA reduced stiffness in posterior chain muscles. PNF increased stiffness in specific muscles, suggesting caution before explosive activities. Full article