Spinal maps in phasic and tonic EMG: Investigating intra-subject and inter-subject variability.

Reaching movements are essential for daily tasks and they have been widely investigated through kinematic, kinetic, and electromyographic (EMG) analyses. Recent studies have suggested that the central nervous system simplifies control of reaching movements by using muscle synergies. An alternative approach is to investigate how EMG activity reflects at theneural level with the representation of spinal maps that visualize the spatiotemporal activity of motoneuronal pools.

Kinematic-Muscular Synergies Describe Human Locomotion with a Set of Functional Synergies.

Kinematics, kinetics and biomechanics of human gait are widely investigated fields of research. The biomechanics of locomotion have been described as characterizing muscle activations and synergistic control, i.e.

Muscle synergies in upper limb stroke rehabilitation: a scoping review.

Introduction: Upper limb impairment is a common consequence of stroke, significantly affecting the quality of life and independence of survivors. This scoping review assesses the emerging field of muscle synergy analysis in enhancing upper limb rehabilitation, focusing on the comparison of various methodologies and their outcomes. It aims to standardize these approaches to improve the effectiveness of rehabilitation interventions and drive future research in the domain.

Transferring Sensor-Based Assessments to Clinical Practice: The Case of Muscle Synergies.

Sensor-based assessments in medical practice and rehabilitation include the measurement of physiological signals such as EEG, EMG, ECG, heart rate, and NIRS, and the recording of movement kinematics and interaction forces. Such measurements are commonly employed in clinics with the aim of assessing patients' pathologies, but so far some of them have found full exploitation mainly for research purposes. In fact, even though the data they allow to gather may shed light on physiopathology and mechanisms underlying motor recovery in rehabilitation, their practical use in the clinical environment is mainly devoted to research studies, with a very reduced impact on clinical practice.

Kinematic synergies show good consistency when extracted with a low-cost markerless device and a marker-based motion tracking system.

Recently, markerless tracking systems, such as RGB-Depth cameras, have spread to overcome some of the limitations of the gold standard marker-based tracking systems. Although these systems are valuable substitutes for human motion analysis, as they guarantee higher flexibility, faster setup time and lower costs, their tracking accuracy is lower with respect to marker-based systems. Many studies quantified the error made by markerless systems in terms of body segment length estimation, articular angles, and biomechanics, concluding that they are appropriate for many clinical applications related to motion analysis.

Biomechanical Analysis of Human Gait When Changing Velocity and Carried Loads: Simulation Study with OpenSim.

Walking is one of the main activities of daily life and gait analysis can provide crucial data for the computation of biomechanics in many fields. In multiple applications, having reference data that include a variety of gait conditions could be useful for assessing walking performance. However, limited extensive reference data are available as many conditions cannot be easily tested experimentally.

SynergyAnalyzer: A Matlab toolbox implementing mixed-matrix factorization to identify kinematic-muscular synergies.

Background And Objective: A new direction in the study of motor control was opened about two decades ago with the introduction of a model for the generation of motor commands as combination of muscle synergies. Muscle synergies provide a simple yet quantitative framework for analyzing the hierarchical and modular architecture of the human motor system. However, to gain insights on the functional role of muscle synergies, they should be related to the task space.

Influence of Backpack Carriage and Walking Speed on Muscle Synergies in Healthy Children.

Four to five muscle synergies account for children's locomotion and appear to be consistent across alterations in speed and slopes. Backpack carriage induces alterations in gait kinematics in healthy children, raising questions regarding the clinical consequences related to orthopedic and neurological diseases and ergonomics. However, to support clinical decisions and characterize backpack carriage, muscle synergies can help with understanding the alterations induced in this condition at the motor control level.

Azure Kinect performance evaluation for human motion and upper limb biomechanical analysis.

Human motion tracking is a valuable task for many medical applications. Marker-based optoelectronic systems are considered the gold standard in human motion tracking. However, their use is not always feasible in clinics and industrial environments.

Phasic and tonic muscle synergies are different in number, structure and sparseness.

In the last two decades, muscle synergies analysis has been commonly used to assess the neurophysiological mechanisms underlying human motor control. Several synergy models and algorithms have been employed for processing the electromyographic (EMG) signal, and it has been shown that the coordination of motor control is characterized by the presence of phasic (movement-related) and tonic (anti-gravity and related to co-contraction) EMG components. Neural substrates indicate that phasic and tonic components have non-homogeneous origin; however, it is still unclear if these components are generated by the same set of synergies or by distinct synergies.

A Narrative Review on Multi-Domain Instrumental Approaches to Evaluate Neuromotor Function in Rehabilitation.

In clinical scenarios, the use of biomedical sensors, devices and multi-parameter assessments is fundamental to provide a comprehensive portrait of patients' state, in order to adapt and personalize rehabilitation interventions and support clinical decision-making. However, there is a huge gap between the potential of the multidomain techniques available and the limited practical use that is made in the clinical scenario. This paper reviews the current state-of-the-art and provides insights into future directions of multi-domain instrumental approaches in the clinical assessment of patients involved in neuromotor rehabilitation.

Biomechanical Assessments of the Upper Limb for Determining Fatigue, Strain and Effort from the Laboratory to the Industrial Working Place: A Systematic Review.

Recent human-centered developments in the industrial field (Industry 5.0) lead companies and stakeholders to ensure the wellbeing of their workers with assessments of upper limb performance in the workplace, with the aim of reducing work-related diseases and improving awareness of the physical status of workers, by assessing motor performance, fatigue, strain and effort. Such approaches are usually developed in laboratories and only at times they are translated to on-field applications; few studies summarized common practices for the assessments.

Spatial and Temporal Muscle Synergies Provide a Dual Characterization of Low-dimensional and Intermittent Control of Upper-limb Movements.

Muscle synergy analysis investigates the neurophysiological mechanisms that the central nervous system employs to coordinate muscles. Several models have been developed to decompose electromyographic (EMG) signals into spatial and temporal synergies. However, using multiple approaches can complicate the interpretation of results.

The Number and Structure of Muscle Synergies Depend on the Number of Recorded Muscles: A Pilot Simulation Study with OpenSim.

The muscle synergy approach is used to evaluate motor control and to quantitatively determine the number and structure of the modules underlying movement. In experimental studies regarding the upper limb, typically 8 to 16 EMG probes are used depending on the application, although the number of muscles involved in motor generation is higher. Therefore, the number of motor modules may be underestimated and the structure altered with the standard spatial synergy model based on the non-negative matrix factorization (NMF).

Biomechanical assessment of the ipsilesional upper limb in post-stroke patients during multi-joint reaching tasks: A quantitative study.

In hemiplegic patients with stroke, investigating the ipsilesional limb may shed light on the upper limb motor control, impairments and mechanisms of functional recovery. Usually investigation of motor impairment and rehabilitative interventions in patients are performed only based on the contralesional limb. Previous studies found that also the ipsilesional limb presents motor deficits, mostly evaluated with clinical scales which could lack of sensibility.

Optimal Biomechanical Performance in Upper-Limb Gestures Depends on Velocity and Carried Load.

In the last few years, there has been increased interest in the preservation of physical and mental health of workers that cooperate with robots in industrial contexts, such as in the framework of the European H2020 Mindbot Project. Since biomechanical analysis contributes to the characterization of the subject interacting with a robotic setup and platform, we tested different speed and loading conditions in a simulated environment to determine upper-limb optimal performance. The simulations were performed starting from laboratory data of people executing upper-limb frontal reaching movements, by scaling the motion law and imposing various carried loads at the hand.

Questioning Domain Adaptation in Myoelectric Hand Prostheses Control: An Inter- and Intra-Subject Study.

One major challenge limiting the use of dexterous robotic hand prostheses controlled via electromyography and pattern recognition relates to the important efforts required to train complex models from scratch. To overcome this problem, several studies in recent years proposed to use transfer learning, combining pre-trained models (obtained from prior subjects) with training sessions performed on a specific user. Although a few promising results were reported in the past, it was recently shown that the use of conventional transfer learning algorithms does not increase performance if proper hyperparameter optimization is performed on the standard approach that does not exploit transfer learning.

Combined Use of EMG and EEG Techniques for Neuromotor Assessment in Rehabilitative Applications: A Systematic Review.

Electroencephalography (EEG) and electromyography (EMG) are widespread and well-known quantitative techniques used for gathering biological signals at cortical and muscular levels, respectively. Indeed, they provide relevant insights for increasing knowledge in different domains, such as physical and cognitive, and research fields, including neuromotor rehabilitation. So far, EEG and EMG techniques have been independently exploited to guide or assess the outcome of the rehabilitation, preferring one technique over the other according to the aim of the investigation.

Life Cycle Air Emissions External Costs Assessment for Comparing Electric and Traditional Passenger Cars.

This study compares the environmental air emissions external costs of electric, gasoline, and diesel private passenger cars during their entire life cycle. The results provide the decision makers with a complementary and unconventional interpretation of the results of an ISO 14040-compliant life cycle assessment (LCA). Indeed, LCA results are often difficult to communicate and to be understood by the general public; on the other hand, an environmental external costs evaluation, where a single monetary value synthesizes the environmental impacts, can be easily understood, communicated to the broad public, and compared with taxes, incentives, and other economic tools.

Investigating the association between Notch3 polymorphism and migraine.

Objective: The aim of the present study was to evaluate whether the functional Notch3 polymorphism T6746C, which is not causative for cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), might be a risk factor for migraine.

Background: It has been recently demonstrated that migraine is characterized by subclinical brain infarctions and white matter lesions. Several genetic risk factors have been associated with migraine, but no study has unraveled a possible relationship between migraine and Notch3, which is involved in vascular damage.

Functional serotonin 5-HTTLPR polymorphism is a risk factor for migraine with aura.

In the present work, we report that the functional serotonin transporter gene promoter (5-HTTLPR) polymorphism is involved in migraine pathogenesis. The distribution of 5-HTTLPR genotypes was significantly different in MA patients (S/S vs. S/L vs.

Cholinesterase inhibitors exert a protective effect on endothelial damage in Alzheimer disease patients.

It has been recently suggested that in Alzheimer disease (AD), the current available therapy with cholinesterase inhibitors (ChEIs) influences platelets amyloid precursor protein (APP) metabolism towards the nonamyloidogenic pathway. In order to investigate whether ChEIs may exert a protective role on vascular damage due to abeta deposition, several parameters of coagulation and fibrinolysis were assessed. Twenty patients with mild AD and 30 age-matched controls entered the study.

Is transient global amnesia a risk factor for amnestic mild cognitive impairment?

Transient Global Amnesia (TGA) is a common condition of unknown aetiology characterised by the abrupt onset of severe anterograde amnesia, which lasts less than 24 hours. Some authors have suggested that subclinical impairment of memory functions may persist for much longer, but neuropsychological assessment lasting years after TGA attack has not been performed so far. The aim of this study was to evaluate longterm cognitive functions in patients with a previous TGA episode.

Intronic CYP46 polymorphism along with ApoE genotype in sporadic Alzheimer Disease: from risk factors to disease modulators.

Increasing biological and clinical findings argue for a link between brain cholesterol turnover and Alzheimer Disease (AD), high cerebral levels of the former increasing Abeta load. Cerebral cholesterol elimination involves two mechanisms dependent on Apolipoprotein E (ApoE) and cholesterol 24-hydroxylase (CYP46). The aim of this study was to evaluate an intronic variation in CYP46 (intron 2, T --> C ) along with ApoE genotype as risk factors for AD and to establish the correlation between CYP46/ApoE polymorphism and disease progression.