Search Results (204)

Attention-deficit/hyperactivity disorder (ADHD) involves difficulties in sustaining attention and resisting distraction. This has motivated the development of feedback-driven environments for cognitive control training. Integrating electroencephalography (EEG) sensors into Virtual Reality (VR) serious games for cognitive therapy remains relatively underexplored and requires reliable, non-invasive brain–computer interfaces. The existing solutions use multi-channel systems that primarily suffer from requiring complex hardware, while not combining motor imagery (MI) with concentration levels. Therefore, this case study evaluates the feasibility and data quality of a lightweight, cost-effective sensor configuration for real-time control of mental state. A non-invasive, eight-channel OpenBCI Cyton board was integrated with an EEG cap using the international 10–20 placement system, alongside a Meta Quest 2 headset, to capture MI and concentration signals directly from the user’s scalp. Signal acquisition was hindered by high impedance and channel railing, which required conductive gel mitigation, while mechanical tension from the VR headset strap introduced motion artifacts and noise. Nevertheless, under stable signal conditions, the optimized eight-channel sensor setup achieved a subject-specific online classification accuracy of up to 90% using the deep learning model “EEGNet”. The findings demonstrate the technical feasibility of acquiring and classifying EEG activity using a low-cost eight-channel sensor configuration in an interactive VR-BCI Serious Gaming application, provided that skin–electrode impedance and mechanical sensor interferences are managed. The results provide a basis for future investigation of such systems in cognitive-training applications, while further studies, including clinical evaluations, are required to assess their applicability in therapeutic contexts. Full article

Background/Objectives: Epidural electrical stimulation (EES) is a valuable intervention for motor recovery after spinal cord injury (SCI). However, evaluating expected outcomes can be challenging due to the difficulty of assessing residual functional connectivity and other key factors underlying the effects of EES. This case study investigates EES with two 8-contact percutaneous electrodes (Perc-EESs) as a prognostic tool and therapeutic bridge for chronic neuromodulation with EES in an individual with clinically motor-complete SCI. Methods: A 40-year-old male (AIS-B, Th5–Th6, >20 years since initial presentation followed by a complex history of progressive deterioration and two subsequent neurosurgical interventions) underwent a 7-day trial using Perc-EES, followed by chronic 5-6-5 Medtronic lead (Paddle-EES) implantation at the L2–S1 segments. Volitional motor control and EMG activity was assessed across three stages: Perc-EES at 5, 7, and 10 days post-enrollment; Paddle-EES at 13, 15, and 18 days post-enrollment; and at a 1-year follow-up (Paddle-EES (1y)). Evaluations were performed in side-lying and upright positions. Results: Without EES, no visible movements were observed. Perc-EES facilitated rhythmic EMG activity and initial voluntary movements, providing an early proof-of-concept that Perc-EES could serve as a preliminary assessment of the patient’s responsiveness to neuromodulation. Paddle-EES (1y) demonstrated a further improvement in motor coordination. Analysis using the Rudolph coefficient showed a distinct shift toward zero. This shift reflects stimulation-associated changes in EMG coordination, moving away from co-activation toward a more alternating activation pattern across side-lying and upright positions. Conclusions: This single-patient feasibility case study suggests that trial Perc-EES may have potential in determining the long-term benefits of chronic Paddle-EES in motor activation after SCI. While these conclusions remain preliminary, these findings can further serve as a potential diagnostic tool to optimize electrode placement and enhance overall recovery in motor-complete SCI patients. Full article

Electromyography (EMG)-based sensing is an important tool for assessing neuromuscular activity and monitoring athlete development; its reliability depends on electrode placement, signal quality, and accurate identification of muscle activation periods. This study proposes an intelligent EMG sensing framework integrating preliminary electrode placement assessment, muscle activity detection, feature extraction, and regression-based progression prediction. A placement assessment indicated that positioning the electrode adjacent to the innervation zone produced the highest RMS under the tested conditions. A two-stage activity detection method based on clustering and probabilistic modeling achieved an average error of 1.5% and a temporal deviation of 19 ms. Nine time-domain EMG features extracted from the detected activity segments were used to characterize athlete progression and estimate the time required to reach a reference neuromuscular profile. Among the methods, Linear Regression provided the best fit to the data, obtaining R² = 0.987 and RMSE = 4.21 and suggesting a predominantly linear relationship between the EMG-derived features and training duration within the dataset. However, these results were obtained from only six longitudinal observation periods for a single representative athlete, with each period represented by a 90-dimensional EMG feature vector derived from the ten movement classes. Therefore, the results should be interpreted as preliminary, athlete-specific goodness-of-fit findings rather than evidence of generalizable predictive performance. Validation using larger longitudinal cohorts and independent datasets is required. The proposed framework is compatible with future IoT-enabled wearable and edge-computing architectures; however, hardware-level implementation was beyond the scope of this study. Full article

Background/Objectives: Spinal cord epidural stimulation (scES) holds significant potential for restoring autonomic function after chronic spinal cord injury (SCI). A significant and often debilitating sequela of SCI is neurogenic lower urinary tract dysfunction, characterized by loss of voluntary bladder control, which adversely impacts patients’ dignity, urological health, and overall quality of life. In a pilot study of three individuals with SCI, an epidural electrode array was implanted between L2 and sacral segments to modulate lower urinary tract function for efficient emptying. Methods: Three participants with chronic thoracic clinically complete SCI were implanted with an epidural stimulator over the lumbosacral spinal cord. Array placement was confirmed using intraoperative and postoperative spatiotemporal mapping of known motor neuron pools following published protocols. In a controlled laboratory mapping, bladder storage and voiding neural networks were targeted during filling cystometry by interactively optimizing lower urinary tract stimulation parameters (electrode configuration, frequency, intensity, and pulse width). Efficacy was assessed during six-hour laboratory sessions of natural bladder filling, followed by approximately four months of daily at-home use. Results: Pre-implant cystometry revealed poor voiding efficiency and absent bladder sensation. Following bladder scES mapping and home training, one of the three participants regained direct bladder sensation, exceeded the 90% clinical threshold for efficient voiding, and continues to use scES for bladder management instead of intermittent catheterization, with no urinary tract infections reported since completion of training (February 2022). The inability of two participants to attain high voiding efficiency may be due to suboptimal adherence to prescribed bladder training protocols in one case and the presence of an elevated bladder neck in the other. All three participants reported off-target improvements in bowel and sexual functions. Conclusions: The present novel pilot study provides the first evidence supporting the potential use of epidural stimulation for bladder management and the importance of activity-based recovery training for durable performance. Full article

Reproducible electrode placement remains a critical, unresolved challenge in wearable ECG systems, where manual electrode attachment introduces inter-session positional error that degrades signal morphology and compromises multi-lead representation. Although the 12-lead clinical ECG system is the gold standard, conventional setups are often bulky, wired, and dependent on operator expertise, limiting their use in prehospital or remote care. Recent advancements in wearable and wireless ECG systems have improved mobility and real-time monitoring, but they typically suffer from limited lead coverage, discomfort, and unstable connectivity. This paper introduces BioShield-12, an anatomically adaptive thermoplastic polyurethane (TPU) shield fabricated using fused deposition modeling (FDM) to improve multi-site electrode placement and 12-lead electrocardiogram (ECG) reconstruction from a single-shield design based on anthropometric data from ten healthy adults (five male, five female; sizing cohort). Mechanical characterization confirmed TPU’s suitability as a compliant wearable substrate, with toughness of 34.4 MJ/m³ and elastic modulus of 79.1 MPa. Feasibility validation against a research-grade reference (BIOPAC MP36) in twenty healthy subjects (n = 20; 10 male, 10 female; mean age 21 ± 4 years) demonstrated consistent signal fidelity (SNR: 17.5–22.5 dB; Pearson r: 0.93–0.98; power-line interference ratio (PLIR): 1.0–3.2 × 10⁻⁵) and confirmed feasibility of 12-lead reconstruction. This work provides proof-of-concept for an additive manufacturing-based conformal electrode interface that eliminates variability in placement without needing individual attachment. Full article

When a wearable gait predictor is personalized to a new user, a short calibration session may contain missing channels, sensor-placement changes, electrode shift, noise, fatigue, or other non-ideal effects. Treating all calibration samples as equally trustworthy can overpersonalize the prediction head and induce harmful drift away from the source model. We study calibration quality as a control signal for new-user personalization and propose Dynamic Trust-Region Head Adaptation (DTR-HA), a head-only adaptation rule that combines reliability-weighted calibration loss with a reliability-scaled source-head anchor. The temporal encoder is frozen, and lower reliability strengthens a soft source-head penalty. The Bilateral Lower-Limb Neuromechanical Signals dataset (BLISS) defines the target early gait-phase prediction task with 21-subject leave-one-subject-out evaluation; complete-bout calibration/test separation; and 0, 100, and 200 ms horizons. K2MUSE supplies real non-ideal calibration conditions for mechanism-level stress testing. In K2MUSE 75% bad-calibration tests with a held-out blind context-based reliability scorer, DTR-HA reduced empirical risk by 20–23% relative to plain head adaptation, improved macro-F1 by 0.018–0.022, and achieved 25/28 paired subject–condition wins with fewer negative-adaptation cases. In a secondary BLISS calibration-pollution check, DTR-HA kept macro-F1 within 0.003 of plain head adaptation while reducing calibration-induced head drift across all horizons. These results support calibration quality as an adaptation-stage control signal for stable, lightweight wearable gait personalization under unreliable calibration. Full article

Background/Objectives: Electroconvulsive therapy (ECT) remains the most effective biological treatment for treatment-resistant depression. Although its efficacy has been consistently demonstrated, the influence of seizure characteristics and treatment parameters on clinical outcomes in routine practice remains incompletely understood. This study aimed to evaluate the effectiveness of seizure threshold-titrated ECT in patients with treatment-resistant depression and to describe treatment outcomes in relation to seizure expression and technical treatment variables. Methods: We conducted a retrospective naturalistic study at the Department of ECT, Dr. Gh. Preda Clinical Psychiatric Hospital, Sibiu, Romania. Consecutive patients treated with ECT for treatment-resistant depressive episodes between March 2022 and December 2025 were included. Clinical outcomes were assessed before and after treatment using the Montgomery–Åsberg Depression Rating Scale (MADRS), Beck Depression Inventory (BDI), Mini-Mental State Examination (MMSE), and Global Assessment of Functioning Scale (GAF). Information regarding electrode placement, seizure threshold, seizure duration, the number of ECT sessions, and concomitant psychotropic medication was collected from medical records. Results: Nineteen acute ECT courses were available for outcome analysis. Depressive symptom severity improved significantly following treatment, with median MADRS scores decreasing from 38 (IQR 36–41) to 20 (IQR 9.5–24) (p < 0.001). A clinical response was observed in 57.9% of courses, while 36.8% achieved remission. Similar improvements were noted in self-reported depressive symptoms and overall functioning, with median BDI scores decreasing from 38 to 16 and median GAF scores increasing from 55 to 65. MMSE scores remained stable throughout treatment. Considerable variability was observed in both motor and EEG seizure durations; however, no consistent relationship between seizure duration and antidepressant response was identified. Discussion: The observed outcomes are consistent with previous evidence supporting ECT as an effective intervention for severe depressive illness. Functional improvement accompanied symptom reduction, while no decline in global cognitive performance, as assessed by the MMSE, was observed. In this cohort, seizure duration alone did not appear to provide meaningful information regarding treatment response. Conclusions: Seizure threshold-titrated ECT was associated with substantial clinical improvement in patients with treatment-resistant depressive episodes, accompanied by improved functioning and stable global cognitive performance. These findings support the continued use of individualized ECT protocols in routine clinical practice and highlight the need for further research on neurophysiological predictors of treatment outcome. Full article

Radio-frequency (RF) heating has been proven effective in inactivating foodborne pathogens or fungi in spices. However, non-uniformity heating remains a major obstacle limiting RF treatment application in the commercial pasteurization of irregularly shaped spices. This study evaluated the effects of star anise arrangement, packaging materials, and dual-bag placement on RF heating uniformity after identifying the optimal input power and electrode gap. The optimal conditions were 400 W and an electrode gap of 5 cm. Under these conditions, heating uniformity was significantly improved by a staggered arrangement, using bags with 0.16 mm aluminum foil (plastic/foil composite) and face-to-face placement of two bags; the average heating uniformity index of the stacked packages decreased from 0.30 to 0.135, corresponding to a reduction of approximately 55.0%. These findings provide practical guidance for scalable, eco-friendly RF pasteurization of irregular spice products, emphasizing key considerations in sample arrangement and packaging/bag placement to control heating uniformity. Full article

Surface electromyography (sEMG) is widely used to evaluate neuromuscular activity; however, objective and reproducible methodologies for assessing signal quality in embedded acquisition systems remain limited. This study presents a multichannel embedded sEMG acquisition platform based on an ADS1298 analog front-end (Texas Instruments, Dallas, TX, USA) and an STM32H743ZIT6 microcontroller (STMicroelectronics, Geneva, Switzerland), together with a signal-quality evaluation methodology guided by signal-integrity principles derived from IEC 60601-2-40. sEMG signals were acquired at 2 kHz from 10 healthy participants during standardized submaximal isometric and controlled isotonic contractions using consistent electrode placement and acquisition procedures. Signal quality was quantified using complementary temporal and spectral metrics, including signal-to-noise ratio (SNR), power-line interference ratio (PLI), baseline drift, root mean square stability, median frequency, spectral entropy, skewness, and kurtosis. Signal conditioning reduced the baseline drift from 0.32 ± 0.23 to 0.004 ± 0.003 and reduced PLI from 0.097 ± 0.135 to 0.010 ± 0.003 while preserving contraction-dependent temporal and spectral characteristics. In addition, envelope-based Spearman correlation analysis revealed contraction-dependent intermuscular coordination patterns between the long and short heads of the biceps brachii under controlled acquisition conditions. These findings demonstrate that combining standardized acquisition protocols, objective signal quality metrics, and interpretable correlation-based analysis provides a reproducible engineering framework for evaluating embedded sEMG systems and establishes a foundation for future machine learning approaches based on larger and well-characterized physiological datasets. Full article

Objective fitting measures offer a means to circumvent the subjectivity of cochlear implant programming, with the stapedius reflex representing one robust predictor of the maximum comfortable loudness level. With the present study, it was investigated whether long-term electromyographic measurements of the stapedius muscle using implanted electrodes are feasible. In nine sheep, myoelectrical activities were recorded intraoperatively and synchronized with middle ear admittance as a reference signal. For acoustic stimulation pure tones with different frequencies were used. The electrodes were placed at the stapedius muscle surface after exposing it via the retrofacial approach. EMG-based detection of the stapedius reflex was achievable over six months when electrode integrity and placement were preserved. The treated muscles were subsequently excised, cut and examined histologically. No signs of atrophy were found in the muscles examined. However, the histological section series showed a clear division of the muscle from proximal to distal, the ratio between tendon and muscle fibers being most pronounced in favor of the muscle fibers in the proximal section. The integration of an electromyography-based measurement method for the objective determination of the stapedius reflex threshold and thus, for the long-term adjustment of cochlear implants, appears possible and could potentially enable autonomous fitting of implants. Full article

Bioelectrical impedance analysis (BIA) is a widely used technique in clinical and research settings because it provides non-invasive estimates of body composition. However, the quality of a measurement depends on more than the perceived accuracy and precision of numbers produced by a BIA device. This review considers BIA through the lens of metrology, defined as the science of measurement. It highlights several key factors that affect measurement quality. These include accuracy, precision, calibration, standardisation, and uncertainty quantification, all of which are essential for meaningful, clinically feasible BIA measurements. Applying prediction equations generated by the device outside their intended context, poor electrode placement, or uncalibrated devices can introduce bias, whereas biological variability can complicate the interpretation of bioimpedance results. The traditional emphasis on using a reference method for validation is considered along with clinical relevance, which is argued to be an equally important benchmark for evaluating measurement utility. We also present best practices and practical guidelines for improving measurement quality, interpretation, and integration into clinical workflows. By adopting a metrological mindset in clinical practice and treating BIA with the same rigour as other diagnostic tools, its utility in areas such as fluid management, nutrition, and preventive health can be further enhanced. Trustworthy decisions depend not only on the data itself but also on how it is measured, interpreted, and used. Full article

Background/Objectives: For patients with profound deafness resulting from auditory nerve pathology, as in Neurofibromatosis type 2, auditory brainstem implantation (ABI) can restore meaningful acoustic input. The literature reporting real-world results for ABI users is limited, especially regarding patients with bilateral implants. Here, we provide an updated report on the audiologic outcomes among all ABI patients treated at a tertiary institution, including high-performing bilateral ABI users. Methods: In this updated and expanded retrospective case series, audiologic outcomes were reviewed in sixteen consecutive patients who underwent ABI placement by a single neurosurgeon-neurotologist team at our center since 2018. Implantation in four of these patients was on their second side after having undergone first side implantation prior to receiving care at our hospital. Main outcome measures were sound awareness (sound-field threshold testing) and speech understanding (pattern perception, spondee, open-set speech testing). Results: Sound awareness was achieved in 100% of patients (16/16) using an average of 12 electrodes (range 7–20). Persistent non-auditory sensations were reported by 12.5% (2/16). Postoperative speech differentiation (with or without lip-reading) was experienced in 87.5% (14/16). Two second-sided ABI recipients experienced exceptional outcomes as high-performing outliers: one achieved 57% audio only and 86% audio + visual hearing in noise test (HINT) sentence scores; the second bilateral user scored 92% with auditory-only input. Conclusions: ABI represents a viable option for patients who are at risk of developing bilateral profound deafness resulting from auditory nerve disruption. Second sided device implantation is safe and has the potential to significantly improve auditory outcomes. Full article

This study investigates the controllability of a hovering platform based on ion thrust generated through the Biefeld–Brown effect. The primary objective is to examine the feasibility of stabilizing a triangular structure under laboratory conditions. To this end, three custom high-voltage power supplies were developed, each independently controlled. These power supplies can be modulated through the control loop, enabling closed-loop adjustment of thrust levels and allowing assessment of how electrode placement influences stability. Two electrode configurations were tested: edge-based placement, where thrust is produced along the triangle’s sides, and vertex-based placement, where thrust is generated near the corners. Experimental results demonstrated that, while both configurations provide similar lifting capability, the vertex-based configuration significantly improves stabilization and orientation control. The improvement stems from reduced actuator coupling and a larger effective moment arm relative to the platform’s center of mass, enabling more efficient torque generation. Full article

Objective: Electrocorticography can serve as an intraoperative research tool during deep brain stimulation procedure, when patients are awake to participate in behavioral tasks or to allow recordings while awake but at rest. This report aims to describe the electrocorticography methods used in awake patients undergoing deep brain stimulation surgery at a single center and to describe the feasibility, safety, and usefulness of high-density electrocorticography for capturing high-resolution neurophysiological data during deep brain stimulation surgery. We hypothesize that the use of high-density electrocorticography and multi-subject integration of cortical data enables improved spatial resolution and data analysis compared to prior studies employing lower-density electrodes and primarily single-subject analyses. Methods: Data were obtained from patients undergoing awake deep brain stimulation surgery for the treatment of Parkinson’s disease or essential tremor at Johns Hopkins Hospital between March 2022 and September 2024. Electrophysiological and anatomical data were analyzed, with localization in the anterior commissure and posterior commissure and Montreal Neurological Institute coordinate systems. Surgical complications were monitored for at least six months postoperatively. Results: Thirty-six patients (26 with Parkinson’s disease, 10 with essential tremor) were enrolled in the study. In one case, anatomical placement was inadequate for neurophysiological analysis. Postoperative complications included three infections (8.3%) and one chronic subdural hematoma (2.8%), with no permanent neurological deficits. Observed complication rates were within the range reported in the literature for standard deep brain stimulation surgeries without electrocorticography. Anatomical and neurophysiological analysis demonstrated high-resolution cortical mapping. Multiple-subject level analysis using high-density electrocorticography yielded over 1300 electrode positions. Conclusions: Electrocorticography during deep brain stimulation is a valuable research method for movement disorders and, based on a moderate sized consecutive clinic sample, appears safe with risks no greater than those associated with DBS surgery itself. Full article

The evolution toward sixth-generation (6G) networks envisions humans as active nodes within a fully interconnected digital ecosystem, supported by data collected from in-body and on-body sensors. Since many of these devices are not equipped to connect directly to 6G networks, Wireless Body Area Networks (WBANs) serve as an essential intermediate layer. However, conventional radio-frequency technologies face limitations in terms of energy efficiency, security, and data integrity, motivating the adoption of lightweight security mechanisms. Physical Layer Security (PLS), and in particular Physical Key Extraction (PKE), offers a promising solution by enabling legitimate devices to derive shared cryptographic keys from the reciprocal properties of the communication channel. Galvanic coupling (GC) communication has recently emerged as an on-body transmission technology alternative to radio-frequency (RF), which exploits low-power electrical signals propagating through biological tissue. Building on prior feasibility studies, this work proposes a PKE framework tailored to GC channels, integrating a lightweight key reconciliation method, based on Hamming (7,4) error-correction codes, and evaluating system performance through dedicated reliability and security Key Performance Indicators (KPIs). Results reveal a trade-off shaped by electrode placement and channel quantization parameters. Among the ones tested, the optimal configuration is achieved with a 3 cm transverse inter-electrode spacing at both transmitter and receiver, and a 3 cm longitudinal separation between transmitter and receiver, by quantizing the channel impulse response with two quantization bits. While this work focuses on validating the method in controlled conditions in order to establish a reliable study framework, future developments will focus on enhanced reconciliation, privacy amplification, and analysis of the GC channel considering physiological and environmental variations. Full article