Johannes von Fraunberg , Hongyu Lu , Haodi Yang , Nura Marquetand , Christoph Braun , Lukas Rüttiger , Stephan Wolpert , Marlies Knipper , Markus Siegel , Hubert Löwenheim , Justus Marquetand
{"title":"Facial magnetomyography using an array of optically pumped magnetometers","authors":"Johannes von Fraunberg , Hongyu Lu , Haodi Yang , Nura Marquetand , Christoph Braun , Lukas Rüttiger , Stephan Wolpert , Marlies Knipper , Markus Siegel , Hubert Löwenheim , Justus Marquetand","doi":"10.1016/j.cnp.2025.03.003","DOIUrl":"10.1016/j.cnp.2025.03.003","url":null,"abstract":"<div><h3>Objective</h3><div>Measuring facial muscle activity is crucial in the diagnosis of facial palsy. This study investigated whether contactless Magnetomyography (MMG) using optically pumped magnetometers (OPM) is feasible for visualizing facial muscle activity.</div></div><div><h3>Methods</h3><div>An anatomically shaped mask featuring eleven OPM was arranged on one side of the face of five healthy subjects. MMG was recorded while they performed different facial expressions. The root mean square of each OPM signal was calculated for each expression and subject and allocated to the individual face. Moreover, the maximum average muscle activity and the signal-to-noise ratio (SNR) were determined.</div></div><div><h3>Results</h3><div>The subjects’ facial muscle activity could be measured individually per facial expression. Mean RMS was 0.6pT (SD 0.4pT), resulting in a mean SNR of 2.2 (SD 1.2).</div></div><div><h3>Conclusions</h3><div>Imaging facial activity via MMG using OPM is possible, although the sensor positioning (sensor geometry and distance to the muscle) is decisive. However, the signal amplitude of the facial muscles is low and the interindividual anatomical variability renders the measurement setup challenging.</div></div><div><h3>Significance</h3><div>As the imaging of facial MMG is feasible, this study paves the way for future studies using OPM for the diagnosis, monitoring, and rehabilitation of facial muscle and facial nerve disorders.</div></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"10 ","pages":"Pages 134-140"},"PeriodicalIF":2.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143747941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Tankisi , K. Pugdahl , B. Johnsen , J.P. Camdessanché , M. de Carvalho , P. Fawcett , A. Labarre-Vila , R. Liguori , W. Nix , I. Schofield , A. Fuglsang-Frederiksen
{"title":"Electrodiagnostic criteria for neuromuscular transmission disorders suggested by a European consensus group","authors":"H. Tankisi , K. Pugdahl , B. Johnsen , J.P. Camdessanché , M. de Carvalho , P. Fawcett , A. Labarre-Vila , R. Liguori , W. Nix , I. Schofield , A. Fuglsang-Frederiksen","doi":"10.1016/j.cnp.2025.02.011","DOIUrl":"10.1016/j.cnp.2025.02.011","url":null,"abstract":"<div><h3>Objective</h3><div>Electrodiagnostic testing plays an important role in diagnosing disorders of neuromuscular transmission (NMT), especially in seronegative myasthenia gravis. However, electrodiagnostic criteria for the diagnosis are sparse. This study aimed at inferring evidence-based recommendations for the electrodiagnostic examination of NMT disorders.</div></div><div><h3>Methods</h3><div>A total of 164 cases with a consensus diagnosis of NMT disorder obtained by peer review by eight experienced neurophysiologists were analysed for differences in examination strategy, the sensitivity of different tests, and inferring minimal criteria. The diagnostic performance of the suggested criteria was validated on 24 MG patients and 50 patients with neuropathy (17), myopathy (15), or fatigue (18).</div></div><div><h3>Results</h3><div>We recommend as minimal electrodiagnostic criteria for NMT disorders, either (a) 2 abnormal repetitive nerve stimulation (RNS), (b) 1 abnormal RNS and 1 abnormal single fiber electromyography (SFEMG) or (c) 2 abnormal SFEMG. These showed a good diagnostic performance with a sensitivity of 87.5 % and a specificity of 100 %.</div></div><div><h3>Conclusion</h3><div>Recommendations with high diagnostic sensitivity and specificity for the minimum number of RNS and SFEMG studies to diagnose NMT disorders developed by an international consensus group are suggested.</div></div><div><h3>Significance</h3><div>The suggested electrodiagnostic recommendations for diagnosing NMT disorders are reliable and suitable for use at different centres.</div></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"10 ","pages":"Pages 79-83"},"PeriodicalIF":2.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143580359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hosna Elshony , Mohamed H. Aly , Abdelgaffar Mohammed , Abdulrahman M. Hassan , Abdulrahman A. Alshehri , Mohamed Hedak , Rakan Almuhanna , Abdulaziz Al-Ghamdi , Rasha Elsaadawy
{"title":"Asymptomatic tarsal tunnel syndrome in rheumatoid arthritis: An electrophysiological perspective with Insights into clinical and Laboratory correlates","authors":"Hosna Elshony , Mohamed H. Aly , Abdelgaffar Mohammed , Abdulrahman M. Hassan , Abdulrahman A. Alshehri , Mohamed Hedak , Rakan Almuhanna , Abdulaziz Al-Ghamdi , Rasha Elsaadawy","doi":"10.1016/j.cnp.2025.07.003","DOIUrl":"10.1016/j.cnp.2025.07.003","url":null,"abstract":"<div><h3>Objective</h3><div>To evaluate the prevalence of asymptomatic tarsal tunnel syndrome (TTS) in rheumatoid arthritis (RA) patients and its association with disease activity, inflammation, and electrophysiological changes.</div></div><div><h3>Methods</h3><div>Forty RA patients and 40 age- and sex-matched controls underwent nerve conduction studies assessing medial plantar, lateral plantar, and posterior tibial nerves. Disease activity (DAS28, RASS), inflammatory markers (ESR, CRP), and autoantibodies (RF, anti-CCP) were recorded. Comparisons used t-tests; correlations assessed associations.</div></div><div><h3>Results</h3><div>RA patients showed significantly prolonged sensory latencies and reduced amplitudes and nerve conduction velocities, especially in medial and lateral plantar nerves. Sensory latencies had 100% sensitivity for subclinical TTS; motor parameters demonstrated high specificity. Higher DAS28, longer disease duration, elevated ESR/CRP, joint deformities, and seropositivity predicted TTS.</div></div><div><h3>Conclusions</h3><div>Subclinical TTS is highly prevalent in RA and linked to systemic inflammation, disease severity, and structural damage.</div></div><div><h3>Significance</h3><div>Routine electrophysiological screening may enable early detection and intervention, preserving nerve function and improving long-term mobility and quality of life in RA patients.</div></div><div><h3>Trial Registration</h3><div>The study was approved by the SFHM Institutional Review Board and registered under HAP-02-K-052 in August 2024.</div></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"10 ","pages":"Pages 316-323"},"PeriodicalIF":2.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144704111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Stefan Dukic , Rosanne Govaarts , Arjan Hillebrand , Marianne de Visser , Margitta Seeck , Roisin McMackin
{"title":"Novel approaches to EEG and MEG in motor neurone disease: IFCN Handbook Chapter","authors":"Stefan Dukic , Rosanne Govaarts , Arjan Hillebrand , Marianne de Visser , Margitta Seeck , Roisin McMackin","doi":"10.1016/j.cnp.2025.07.001","DOIUrl":"10.1016/j.cnp.2025.07.001","url":null,"abstract":"<div><div>Motor neurone diseases (MNDs) are increasingly being acknowledged as network disorders, with cortical dysfunction and degeneration extending beyond the motor cortex. Measures of this broader cortical pathophysiology are providing promising candidates in the search for diagnostic and prognostic biomarkers of the MNDs. Electroencephalography (EEG) and magnetoencephalography (MEG) offer a direct view of neural network activity by detecting changes in electromagnetic fields of the brain. Measurements based on EEG/MEG have often been overlooked in the search for MND biomarkers, largely due to their limited spatial resolution and the perceived challenges associated with noise in these signals. However, with recent developments in sensor technology and source reconstruction algorithms, alongside substantial improvement in pipelines that address noise, EEG/MEG-based measures can now be readily employed for spatiotemporally-precise, economical and non-invasive characterisation of cortical network pathophysiology in MNDs. Here, we provide an overview of how EEG/MEG signals have been employed to quantify neural network function in MND. We outline the advantages and limitations of these measurements, discuss the most clinically promising EEG/MEG studies of MNDs to date, and highlight future directions warranted to harness the full potential of these technologies for understanding and assessing MNDs.</div></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"10 ","pages":"Pages 301-315"},"PeriodicalIF":2.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144655220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mohammad Mahdi Talimkhani , Ailin Talimkhani , Vida Dinarvand , Somayeh Mohamadi , Hamzeh Baharlouei
{"title":"The effects of multi-session dual-tDCS on the bilateral transfer of motor skill learning in patients with stroke","authors":"Mohammad Mahdi Talimkhani , Ailin Talimkhani , Vida Dinarvand , Somayeh Mohamadi , Hamzeh Baharlouei","doi":"10.1016/j.cnp.2025.06.005","DOIUrl":"10.1016/j.cnp.2025.06.005","url":null,"abstract":"<div><h3>Objective</h3><div>This study investigates the potential effects of combining motor skill learning transfer from the unaffected to the affected hand with multiple sessions of dual-transcranial direct current stimulation (tDCS) over the primary motor cortex to enhance motor skills in stroke patients.</div></div><div><h3>Methods</h3><div>Eleven stroke patients participated in a randomized, sham-controlled, double-blind crossover study. Over two periods separated by a 3-week washout, participants underwent either sham or dual-tDCS concurrently with serial response time tasks (SRTT). Each intervention included 20 min of stimulation during SRTT for three consecutive days. The skill index, the primary variable, was assessed pre-intervention, immediately post-intervention, and 24 h later.</div></div><div><h3>Results</h3><div>Both groups showed significant improvement in motor skill learning across the three intervention days (P < 0.001). The dual-tDCS group demonstrated significantly greater skill improvement in the affected hand compared to the sham group (P < 0.01), while no significant differences were found for the unaffected hand (P = 0.98).</div></div><div><h3>Conclusions</h3><div>Multi-session dual-tDCS combined with motor learning tasks significantly enhances motor skill transfer to the affected hand in stroke patients, with greater and more durable effects compared to sham stimulation.</div></div><div><h3>Significance</h3><div>This approach may improve bilateral motor skill transfer and hand fatigue management in stroke rehabilitation.</div></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"10 ","pages":"Pages 236-245"},"PeriodicalIF":2.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144562781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Brin E. Freund , Khalil S. Husari , José L. Fernández-Torre , Philippe Gélisse , Peter W. Kaplan
{"title":"Triphasic waves: To treat or not to treat?","authors":"Brin E. Freund , Khalil S. Husari , José L. Fernández-Torre , Philippe Gélisse , Peter W. Kaplan","doi":"10.1016/j.cnp.2025.06.001","DOIUrl":"10.1016/j.cnp.2025.06.001","url":null,"abstract":"<div><div>Generalized periodic discharges (GPDs) with triphasic morphology (triphasic waves, TWs) are EEG waveforms that have been a frequent topic of research evaluating their etiology and clinical correlates. More specifically, prior studies have tried to better elucidate their implications regarding seizures to help guide decision making regarding empiric treatment and EEG monitoring and in spite of multiple studies, controversies remain due to disparate findings. In this review we discuss the historical views of TWs and their clinical and radiographic correlates, highlight the typical and atypical features of TWs, discuss the controversy related to the association between TWs and seizures, and propose an approach to their management.</div></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"10 ","pages":"Pages 265-277"},"PeriodicalIF":2.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144605722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Perianen Ramasawmy , Krisztián Iszak , Steffen Brüshaber , Viktória Kállay , Géza Gergely Ambrus , Walter Paulus , Andrea Antal
{"title":"When genetics prevail: brain stimulation fails to overcome learning deficits from brain-derived neurotrophic factor Val66Met","authors":"Perianen Ramasawmy , Krisztián Iszak , Steffen Brüshaber , Viktória Kállay , Géza Gergely Ambrus , Walter Paulus , Andrea Antal","doi":"10.1016/j.cnp.2025.08.009","DOIUrl":"10.1016/j.cnp.2025.08.009","url":null,"abstract":"<div><h3>Background</h3><div>The dorsolateral prefrontal cortex (DLPFC) is a key contributor to memory categorization. Brain-Derived Neurotrophic Factor (BDNF) <em>Val66Met</em> polymorphism affects the efficacy of neuronal plasticity induction. We investigated whether DLPFC-transcranial direct current stimulation (tDCS) influences categorization performance, and whether BNDF genotype modulates this effect.</div></div><div><h3>Methods</h3><div>Sixty-two healthy individuals were randomized to receive 10 min of either anodal right DLPFC-tDCS at 1 mA, or sham tDCS during the training phase of a prototype distortion task. Categorization performance was assessed during, shortly after, and the morning following the stimulation. <em>Val66Met</em> polymorphism status was determined through BNDF genotyping.</div></div><div><h3>Results</h3><div><em>Val66Met</em> carriers showed poorer categorization ability than <em>Val/Val</em> homozygotes (p < 0.0001). tDCS did not enhance categorization performance overall, or reduce genotype-associated differences with these specific stimulation parameters. However, tDCS extinguished the prototype effect of the categorization task observed in our sample.</div></div><div><h3>Conclusions</h3><div>Our findings underscore the importance of BDNF polymorphism in category learning. 1 mA anodal right DLPFC over the right DLPFC does not improve performance or offset genotype differences under tested conditions.</div></div><div><h3>Significance</h3><div>BDNF <em>Val66Met</em> polymorphism influences category learning, and low-intensity tDCS does not counteract this effect, emphasizing the need to refine stimulation protocols for genotype-specific cognitive enhancement.</div></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"10 ","pages":"Pages 350-358"},"PeriodicalIF":2.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145007533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Giridhar P. Kalamangalam , Subeikshanan Venkatesan , Maria-Jose Bruzzone , Yue Wang , Carolina B. Maciel , Sotiris Mitropanopoulos , Jean Cibula , Kajal Patel , Abbas Babajani-Feremi
{"title":"COMPRESSIVE DATA STORAGE FOR LONG-TERM EEG: VALIDATION BY VISUAL ANALYSIS","authors":"Giridhar P. Kalamangalam , Subeikshanan Venkatesan , Maria-Jose Bruzzone , Yue Wang , Carolina B. Maciel , Sotiris Mitropanopoulos , Jean Cibula , Kajal Patel , Abbas Babajani-Feremi","doi":"10.1016/j.cnp.2025.07.005","DOIUrl":"10.1016/j.cnp.2025.07.005","url":null,"abstract":"<div><h3>Objectives</h3><div>Long-term EEG monitoring (LTM) in acute neurology generates massive data volumes. We investigated whether data-analytic techniques could reduce LTM data size yet conserve their visual diagnostic features.</div></div><div><h3>Methods</h3><div>LTM exemplars from 50 patients underwent singular value decomposition (SVD). High-variance SVD components were transformed using discrete cosine transform (DCT), and significant elements run-length encoded. Two regimes were tested: (I) SVD and DCT compression ratio (CR) of 1.7 and 12, and (II) CR of 3.7 and 5.7; each achieved an overall CR of ≈20. Compressed data were reconstructed alongside uncompressed originals, to create a total of 200 recordings that were scored by two blinded reviewers. Scores of original and reconstructed data were statistically analyzed.</div></div><div><h3>Results</h3><div>Score differences between original recordings were smaller than comparisons involving reconstructions using the first regime but did not differ significantly from reconstructions using the second regime.</div></div><div><h3>Conclusions</h3><div>Raw LTM EEG has sufficient redundancy to undergo extreme (20-fold) data compression without compromising visual diagnostic information. A balanced mix of SVD and DCT appears to be a suitable data-analytic pipeline for achieving such compression.</div></div><div><h3>Significance</h3><div>Dimension reduction is a significant goal in managing big biomedical data. Our results suggest a pathway for archival of meaningful representations of entire LTM datasets. The latent space suggests new lines of data-scientific inquiry of the EEG in acute neurological illness.</div></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"10 ","pages":"Pages 331-339"},"PeriodicalIF":2.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144779854","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Raphael Hamel , Peter Gaskell , Sophie Prosser , Darren Whelan , Richard Irving , Raymond Francis Reynolds
{"title":"Optimising electrical vestibular stimulation (EVS) for assessing vestibular function","authors":"Raphael Hamel , Peter Gaskell , Sophie Prosser , Darren Whelan , Richard Irving , Raymond Francis Reynolds","doi":"10.1016/j.cnp.2025.08.006","DOIUrl":"10.1016/j.cnp.2025.08.006","url":null,"abstract":"<div><h3>Objective</h3><div>Electrical vestibular stimulation (EVS) exhibits similar diagnostic performance to caloric irrigation for assessing interaural vestibular asymmetry. To optimise EVS for clinical uses, we investigated the influence of EVS stimulus parameters upon absolute torsional eye response amplitude and asymmetry assessments.</div></div><div><h3>Methods</h3><div>In young healthy adults (n = 72), monoaural sinusoidal EVS was delivered to each mastoid process for 40 s whilst ocular torsion was assessed. Ambient lights, electrode montage, and stimulus frequency were systematically manipulated.</div></div><div><h3>Results</h3><div>Ambient lights (250 lx) attenuated torsional responses by 20 % compared to darkness. When the reference electrode was next to C7 (i.e., mastoid-C7 montage), responses to monoaural stimuli were 50 % those of binaural stimulation. Sinusoidal stimuli at 0.5 Hz evoked torsional responses 250 % larger than at 2 Hz but required 300 % more time to estimate asymmetry (12sec vs 4sec). Perceived discomfort was lower at 0.5 Hz than at 2 Hz. Pooled results (n = 53) suggest a normative asymmetry range of 0 ± 25 % for assessing pathological asymmetry.</div></div><div><h3>Conclusions</h3><div>Darkness and lower stimulus frequencies optimise absolute torsional eye response amplitude. Higher stimulus frequencies accelerate asymmetry assessments. To activate a single vestibular end organ, a mastoid-C7 (or mastoid-acromioclavicular) montage should be used.</div></div><div><h3>Significance</h3><div>These results extend the clinical potential of EVS for assessing vestibular function.</div></div>","PeriodicalId":45697,"journal":{"name":"Clinical Neurophysiology Practice","volume":"10 ","pages":"Pages 359-377"},"PeriodicalIF":2.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145026764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}