Paralyzed Muscles Research Articles

Transcutaneous electrical acupoint stimulation for upper limb motor recovery after stroke: a systematic review and meta-analysis

BackgroundTranscutaneous electrical acupoint stimulation (TEAS) is an innovative, non-invasive therapy that stimulates the contraction of paralyzed muscles in the upper limbs, promoting functional recovery. Several studies have demonstrated the efficacy of TEAS in restoring upper limb function. This study aims to evaluate the impact of TEAS on upper limb motor recovery after stroke.ObjectivesThis study aims to evaluate the influence of TEAS on upper limb motor recovery after stroke and improve the quality of life in such patients.MethodsEight databases were systematically searched from inception to 1st October 2024. Two independent reviewers conducted the screening and data extraction of the study. The primary outcome measure was the Fugl Meyer Assessment of the Upper Extremity (FMA-UE), which evaluates upper extremity motor function in stroke patients. Secondary outcomes included the Modified Ashworth Scale (MAS) for assessing spasticity and the Modified Barthel Index (MBI) to evaluate patients’ abilities to perform activities of daily living. Data synthesis was conducted using RevMan 5.4 and Stata 14.0. The GRADE method was employed to assess the quality of evidence.ResultsA total of 16 trials involving 1,218 stroke patients were included in this meta-analysis. Meta-analysis showed that the TEAS significantly improved upper limb function (SMD = 1.70, 95CI% = 1.09 to 2.31, p < 0.00001, I2 = 93%; low certainty of evidence), reduced spasticity (SMD = −1.18, 95CI% = −1.79 to −0.58, p < 0.00001, I2 = 90%; very low certainty of evidence), and enhanced the ability to perform daily activities (SMD = 1.53, 95CI% = 0.85 to 2.20, p < 0.00001, I2 = 95%; low certainty of evidence).ConclusionOur results indicated that TEAS improved motor function and functional activities and reduced muscle tone in the upper limbs after stroke. However, these results should be interpreted with caution due to the limited strength of the evidence. High-quality, larger sample, multi-center studies are needed to validate these preliminary findings.Systematic review registrationThis study was registered on PROSPERO with registration number CRD42024592509. https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42024592509

Deep Learning and IoT-Based Ankle-Foot Orthosis for Enhanced Gait Optimization.

This paper proposes a method for managing gait imbalances by integrating the Internet of Things (IoT) and machine learning technologies. Ankle-foot orthosis (AFO) devices are crucial medical braces that align the lower leg, ankle, and foot, offering essential support for individuals with gait imbalances by assisting weak or paralyzed muscles. This research aims to revolutionize medical orthotics through IoT and machine learning, providing a sophisticated solution for managing gait issues and enhancing patient care with personalized, data-driven insights. The smart ankle-foot orthosis (AFO) is equipped with a surface electromyography (sEMG) sensor to measure muscle activity and an Inertial Measurement Unit (IMU) sensor to monitor gait movements. Data from these sensors are transmitted to the cloud via fog computing for analysis, aiming to identify distinct walking phases, whether normal or aberrant. This involves preprocessing the data and analyzing it using various machine learning methods, such as Random Forest, Decision Tree, Support Vector Machine (SVM), Artificial Neural Network (ANN), Long Short-Term Memory (LSTM), and Transformer models. The Transformer model demonstrates exceptional performance in classifying walking phases based on sensor data, achieving an accuracy of 98.97%. With this preprocessed data, the model can accurately predict and measure improvements in patients' walking patterns, highlighting its effectiveness in distinguishing between normal and aberrant phases during gait analysis. These predictive capabilities enable tailored recommendations regarding the duration and intensity of ankle-foot orthosis (AFO) usage based on individual recovery needs. The analysis results are sent to the physician's device for validation and regular monitoring. Upon approval, the comprehensive report is made accessible to the patient, ensuring continuous progress tracking and timely adjustments to the treatment plan.

Transcutaneous spinal cord stimulation neuromodulates pre- and postsynaptic inhibition in the control of spinal spasticity

Aside from enabling voluntary control over paralyzed muscles, a key effect of spinal cord stimulation is the alleviation of spasticity. Dysfunction of spinal inhibitory circuits is considered a major cause of spasticity. These circuits are contacted by Ia muscle spindle afferents, which are also the primary targets of transcutaneous lumbar spinal cord stimulation (TSCS). We hypothesize that TSCS controls spasticity by transiently strengthening spinal inhibitory circuit function through their Ia-mediated activation. We show that 30min of antispasticity TSCS improves activity in post- and presynaptic inhibitory circuits beyond the intervention in ten individuals with traumatic spinal cord injury to normative levels established in 20 neurologically intact individuals. These changes in circuit function correlate with improvements in muscle hypertonia, spasms, and clonus. Our study opens the black box of the carryover effects of antispasticity TSCS and underpins a causal role of deficient post- and presynaptic inhibitory circuits in spinal spasticity.

Distinct Genomic Expression Signatures after Low-Force Electrically Induced Exercises in Persons with Spinal Cord Injury.

People with a spinal cord injury are at an increased risk of metabolic dysfunction due to skeletal muscle atrophy and the transition of paralyzed muscle to a glycolytic, insulin-resistant phenotype. Providing doses of exercise through electrical muscle stimulation may provide a therapeutic intervention to help restore metabolic function for people with a spinal cord injury, but high-frequency and high-force electrically induced muscle contractions increase fracture risk for the underlying osteoporotic skeletal system. Therefore, we investigated the acute molecular responses after a session of either a 3 Hz or 1 Hz electrically induced exercise program. Ten people with a complete spinal cord injury completed a 1 h (3 Hz) or 3 h (1 Hz) unilateral electrically induced exercise session prior to a skeletal muscle biopsy of the vastus lateralis. The number of pulses was held constant. Tissue samples were analyzed for genomic and epigenomic expression profiles. There was a strong acute response after the 3 Hz exercise leading to the upregulation of early response genes (NR4A3, PGC-1α, ABRA, IRS2, EGR1, ANKRD1, and MYC), which have prominent roles in regulating molecular pathways that control mitochondrial biogenesis, contractile protein synthesis, and metabolism. Additionally, these genes, and others, contributed to the enrichment of pathways associated with signal transduction, cellular response to stimuli, gene expression, and metabolism. While there were similar trends observed after the 1 Hz exercise, the magnitude of gene expression changes did not reach our significance thresholds, despite a constant number of stimuli delivered. There were also no robust acute changes in muscle methylation after either form of exercise. Taken together, this study supports that a dose of low-force electrically induced exercise for 1 h using a 3 Hz stimulation frequency is suitable to trigger an acute genomic response in people with chronic paralysis, consistent with an expression signature thought to improve the metabolic and contractile phenotype of paralyzed muscle, if performed on a regular basis.

Development of Ocular Muscle Stimulation Systems and Optimization of Electrical Stimulus Parameters for Paralytic Strabismus Treatment.

Paralysis of the extraocular muscles can lead to complications such as strabismus, diplopia, and loss of stereopsis. Current surgical treatments aim to mitigate these issues by resecting the paralyzed muscle or transposing the other recti muscles to the paralyzed muscle, but they do not fully improve the patient's quality of life. Electrical stimulation shows promise, while requiring further in vivo experiments and research on various stimulation parameters. In this study, we conducted experiments on rabbits to stimulate the superior rectus (SR) muscles using different parameters and stimulation waveforms. To provide various types of electrical stimulation, we developed the ocular muscle stimulation systems capable of both current controlled stimulation (CCS) and high-frequency stimulation (HFS), along with the chip that enables energy-efficient and safe switched-capacitor stimulation (SCS). We also developed electrodes for easy implantation and employed safe and efficient stimulation methods including CCS, SCS, and HFS. The in vivo animal experiments on normal and paralyzed SR muscles of rabbits showed that eyeball abduction angles were proportional to the current and pulse width of the stimulation. With the decaying exponential stimuli of the SCS system, eyeball abductions were 2.58× and 5.65× larger for normal and paralyzed muscles, respectively, compared to the rectangular stimulus of CCS. HFS achieved 0.92× and 0.26× abduction for normal and paralyzed muscles, respectively, with half energy compared to CCS. In addition, the continuous changes in eyeball abduction angle in response to varying stimulation intensity over time were observed.

Ultrasound-Compatible Electrode for Functional Electrical Stimulation.

Functional electrical stimulation (FES) is a vital method in neurorehabilitation used to reanimate paralyzed muscles, enhance the size and strength of atrophied muscles, and reduce spasticity. FES often leads to increased muscle fatigue, necessitating careful monitoring of the patient's response. Ultrasound (US) imaging has been utilized to provide valuable insights into FES-induced fatigue by assessing changes in muscle thickness, stiffness, and strain. Current commercial FES electrodes lack sufficient US transparency, hindering the observation of muscle activity beneath the skin where the electrodes are placed. US-compatible electrodes are essential for accurate imaging and optimal FES performance, especially given the spatial constraints of conventional US probes and the need to monitor muscle areas directly beneath the electrodes. This study introduces specially designed body-conforming US-compatible FES (US-FES) electrodes constructed with a silver nanowire/polydimethylsiloxane (AgNW/PDMS) composite. We compared the performance of our body-conforming US-FES electrode with a commercial hydrogel electrode. The findings revealed that our US-FES electrode exhibited comparable conductivity and performance to the commercial one. Furthermore, US compatibility was investigated through phantom and in vivo tests, showing significant compatibility even during FES, unlike the commercial electrode. The results indicated that US-FES electrodes hold significant promise for the real-time monitoring of muscle activity during FES in clinical rehabilitative applications.

Longitudinal Retrospective Study of a Wearable NMES System to Determine the Effects on Arm Usage in Hemiparetic and Hemiplegic Patients

ABSTRACT Introduction Brain disorders such as traumatic brain injury (TBI), stroke, cerebral palsy (CP), and surgical interventions can result in aberrant motor function in the contralateral limbs, resulting in paralysis, weakness, and/or spasticity. It is known that, in the short term, neuromuscular electrical stimulation (NMES), the application of low-level electrical currents to motor nerves to induce muscle contractions in paralyzed muscles, can stimulate affected muscle groups and increase arm mobility. However, there remains a paucity of longitudinal evidence examining NMES-mediated improvements of arm usage. Objective The aim of this study was to determine the effectiveness of a long-term BioSleeve intervention on the recovery of arm mobility in hemiparetic patients. Study Design The design of this study is a retrospective cohort study. Methods We examined self-reported arm usage in patients with 1) TBI, 2) stroke, 3) hemispherectomy, or 4) CP who wore Axiobionics’ BioSleeve NMES device and compared this to arm usage achieved from years of conventional therapy. Results The device was well-tolerated. Patients reported an average increase in arm usage from 9.9% to 43.5%, with the TBI subcohort reporting a consistent increase in arm usage of 5.7% per year over the treatment period. Conclusions This study supports the literature suggesting that longitudinal NMES can be used to increase arm usage in hemiplegic patients. Clinical Relevance Statement This study supports the use of wearable NMES intervention in the treatment of arm hemiparesis.

Mechanomyography reflects the changes in oxygenated hemoglobin during electrically evoked cycling in individuals with spinal cord injury.

Functional electrical stimulation (FES) cycling has been reported to enhance muscle strength and improve muscle fatigue resistance after spinal cord injury (SCI). Despite its proposed benefits, the quantification of muscle fatigue during FES cycling remains poorly documented. This study sought to quantify the relationship between the vibrational performance of electrically-evoked muscles measured through mechanomyography (MMG) and its oxidative metabolism through near-infrared spectroscopy (NIRS) characteristics during FES cycling in fatiguing paralyzed muscles in individuals with SCI. Six individuals with SCI participated in the study. They performed 30 min of FES cycling with MMG and NIRS sensors on their quadriceps throughout the cycling, and the signals were analyzed. A moderate negative correlation was found between MMG root mean square (RMS) and oxyhaemoglobin (O2Hb) [r = -0.38, p = 0.003], and between MMG RMS and total hemoglobin (tHb) saturation [r = -0.31, p = 0.017]. Statistically significant differences in MMG RMS, O2Hb, and tHb saturation occurred during pre- and post-fatigue of FES cycling (p < 0.05). MMG RMS was negatively associated with O2Hb and muscle oxygen derived from NIRS. MMG and NIRS sensors showed good inter-correlations, suggesting a promising use of MMG for characterizing metabolic fatigue at the muscle oxygenation level during FES cycling in individuals with SCI.

A gazelle optimization expedition for key term separated fractional nonlinear systems with application to electrically stimulated muscle modeling

Various real-time processes are effectively represented with a fractional nonlinear autoregressive exogenous (F-NARX) model where estimation of model parameters is considered as an essential task. In this study, a population-based gazelle optimization algorithm (GOA) inspired by the evolutionary characteristics of gazelle's is exploited for the parameter estimation of the key term-separated F-NARX system. The Grünwald-Letnikov derivative, a fractional order calculus operator is integrated to develop the F-NARX system from a conventional non-linear autoregressive system. The mean square error-based merit function is developed and the effectiveness of the GOA for the F-NARX system is analyzed in terms of speedy convergence, estimation accuracy, complexity and robustness for different noise scenarios. The extendibility of the GOA is assessed through the estimation of stiff parameters of the electrically stimulated muscle model (ESMM) required for rehabilitation of paralyzed muscles. The efficacy of the GOA is endorsed through Wilcoxon signed rank statistical test in comparison with recent counterparts of Runge Kutta optimization algorithm, Whale optimization algorithm, and Harris Hawks optimization algorithm.

A guiding light for stimulating paralyzed muscles.

Improving the performance of closed-loop optogenetic nerve stimulation can reproduce desired muscle activation patterns.

Genomic and epigenomic changes by low force electrically induced exercise of human paralyzed muscle

Musculoskeletal deterioration following complete paralysis, such as after a spinal cord injury, results in osteoporotic bone and atrophic, glycolytic, and insulin-resistant skeletal muscle. Decreased bone integrity can be overloaded with very little force; therefore, high force contractions should be avoided in people with long-term spinal cord injury. Together, these changes compromise systemic metabolism for people with SCI and contribute to the development of secondary non-communicable diseases. Electrically induced exercise training offers a unique strategy to ensure full muscle recruitment without high force levels by using high current intensity and a low stimulation frequency (&lt;5Hz) to prevent force summation of stimulus pulses. While acute epigenomic and genomic changes have been found with this low force exercise method; how long-term training affects skeletal muscle and systemic biomarkers of health remains unknown. Purpose: We seek to determine the long-term genomic and epigenomic response of low-force electrically induced exercise in paralyzed skeletal muscle. Methods: 10 males with a complete SCI completed at least 6-months of unilateral electrically induced exercise training using low-force (3Hz) stimulation. Participants completed at least 5 exercise training sessions per week for at least 6-months. A muscle fatigue assessment and fasting venous blood draw were performed before and after training. Percutaneous muscle biopsies were obtained from a trained and untrained vastus lateralis. Gene expression was measured using the Affymetrix HTA 2.0 array and epigenomic expression was measured using Illumina’s MethylEPIC array. Parametric tests were used to compare pre and post training. All participants provided written consent approved by the University of Iowa Institutional Review Board in compliance with the Declaration of Helsinki. Results: Participants maintained a high compliance by completing 119±19% of the training sessions for 7.2±1.2 months. There was a 115±34% change improvement of the fatigue index after training (p=0.002). Serum concentrations of insulin, hsCRP, and myostatin were decreased by 43±8% (p=0.155), 26±8%(p=0.047), 35±9%(p=0.098) after exercise training, respectively. Serum BDNF increased by 68±14%(p=0.093) after exercise training. There was a strong correlation between the primary principal component and the trained limb (R2=0.20, p=0.046). There were 693 and 671 genes to be significantly up or down regulated after exercise training (FDR &lt; 0.05). Of the genes most responsive to exercise training, MYH6, MYH7, and MYL3 were increased in expression and decreased in median methylation. MSTN and ACTN3 were decreased in genomic expression with an increase in median methylation after exercise training. Conclusions: Low-force electrically induced exercise training improved fatigability, a muscle oxidative phenotype transition, and improved serum biomarkers associated with metabolism and inflammation. Together, these data highlight the impact low-force electrically induced exercise can have on paralyzed muscle and is suggestive that this rehabilitation strategy may provide benefits for people living with paralysis. Research Support: This study was funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development: R01HD084645, R01HD082109. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Rehabilitation Following a Triceps Branch to Axillary Motor Nerve Transfer-A Pragmatic Therapy Guide.

Peripheral motor nerve transfer surgery is a technique that may be used to restore motor function to paralyzed muscles. Motor nerve transfer involves harvesting an expendable motor nerve branch, and transfer to the motor branch of the denervated target muscle, using microsurgical coaptation. To date, a standardized rehabilitation protocol does not exist. The 6 stages of rehabilitation after motor nerve transfer surgery were outlined by colleagues in the Birmingham Peripheral Nerve Injury service in 2019. This article aims to provide a practical therapy perspective on the rehabilitation stages of motor nerve transfer surgery outlined in that paper, focusing on the radial to axillary nerve transfer. Timeframes for each stage along with exercise prescription and rationale are provided.

Comparative electromyography analysis of subphase gait disorder in chronic stroke survivors.

Abnormal lower limb muscle activity is the most common cause of the alterative pattern of gait in stroke survivors, resulting from spastic and paralytic muscles around the hip, knee, and ankle joints. However, the activity of the major lower limb muscles that control the legs to facilitate walking in stroke patients have not been clearly understood in each subphase of the gait. This study differentiated the characteristics of surface electromyography (sEMG) signals of lower limb muscles during four subphases of gait cycle between stroke patients and healthy subjects. Sixteen chronic stroke patients and sixteen healthy subjects were recruited. All participants completed three walking trials with a self-selected walking speed. The sEMG signals were recorded on the gluteus medius, rectus femoris, long head of biceps femoris, medial gastrocnemius, tibialis anterior, and peroneus longus muscles. The characteristics of sEMG signals were processed and analyzed in the time and frequency features, considering the first double support, single support, second double support, and swing phases of the gait cycle.The stroke patients had altered sEMG characteristics on both paretic and non-paretic sides compared to healthy subjects across the sub-phases of gait cycle for all six muscles. All time domain features of sEMG signal showed that the medial gastrocnemius muscle has the most significant impaired activity (p<0.05) and affected gait disturbance during all four subphases of the gait cycle. The findings demonstrated that the medial gastrocnemius muscle had impaired activity and was most affected during all four sub-phases of the gait cycle. This indicates that sEMG of medial gastrocnemius muscle can be used to measure the improvement of gait rehabilitation.

The Orthotic Effects of Different Functional Electrical Stimulation Protocols on Walking Performance in Individuals with Incomplete Spinal Cord Injury: A Case Series.

Functional electrical stimulation (FES) of paralyzed muscles can facilitate walking after spinal cord injury (SCI). To test the orthotic effects of different FES walking protocols on lower joint kinematics and walking speed. Three adults with incomplete SCI participated in this study. Their lower extremity motor scores and 10-meter walk test results were as follows: subject A: 50, 1.05 m/s, subject B: 44, 0.29 m/s, and subject C: 32, 0.27 m/s. Participants completed four conditions of over-ground walking including no FES and three bilateral FES-walking protocols as follows: multi-muscle stimulation (stimulation of quadriceps and gastrocnemius in the stance phase, and hamstring and tibialis anterior in the swing phase), drop foot (tibialis anterior stimulation), and flexor withdrawal (common peroneal nerve stimulation). The FES system obtained gait phase information from foot switches located under the individuals' heels. Three-dimensional kinematic analysis was undertaken to measure minimum toe clearance (MTC); ankle, knee, and hip range of motion (ROM); stride length; and stride speed. Compared to no-FES walking, MTC increased during drop foot (all subjects), flexor withdrawal (subjects A and B), and multi-muscle stimulation (subjects B and C) protocols. A significant decrease in ankle ROM was seen with drop foot (all subjects), flexor withdrawal (subjects A), and multi-muscle stimulation (subjects A and C) protocols. Hip ROM increased with drop foot (subjects B and C), flexor withdrawal (subject B), and multi-muscle stimulation (subject C) protocols. Three FES walking protocols induced positive kinematic changes as indicated by increased MTC, decreased ankle ROM, and increased hip ROM during walking in subjects with incomplete SCI.

Enhanced selectivity of transcutaneous spinal cord stimulation by multielectrode configuration.

Transcutaneous spinal cord stimulation (tSCS) has been gaining momentum as a non-invasive rehabilitation approach to restore movement to paralyzed muscles after spinal cord injury (SCI). However, its low selectivity limits the types of movements that can be enabled and, thus, its potential applications in rehabilitation. In this cross-over study design, we investigated whether muscle recruitment selectivity of individual muscles could be enhanced by multielectrode configurations of tSCS in 16 neurologically intact individuals. We hypothesized that due to the segmental innervation of lower limb muscles, we could identify muscle-specific optimal stimulation locations that would enable improved recruitment selectivity over conventional tSCS. We elicited leg muscle responses by delivering biphasic pulses of electrical stimulation to the lumbosacral enlargement using conventional and multielectrode tSCS. Analysis of recruitment curve responses confirmed that multielectrode configurations could improve the rostrocaudal and lateral selectivity of tSCS. To investigate whether motor responses elicited by spatially selective tSCS were mediated by posterior root-muscle reflexes, each stimulation event was a paired pulse with a conditioning-test interval of 33.3 ms. Muscle responses to the second stimulation pulse were significantly suppressed, a characteristic of post-activation depression suggesting that spatially selective tSCS recruits proprioceptive fibers that reflexively activate muscle specific-motor neurons in the spinal cord. Moreover, the combination of leg muscle recruitment probability and segmental innervation maps revealed a stereotypical spinal activation map in congruence with each electrode's position. Improvements in muscle recruitment selectivity could be essential for the effective translation into stimulation protocols that selectively enhance single-joint movements in neurorehabilitation.&#xD.

Preservation of functional descending input to paralyzed upper extremity muscles in motor complete cervical spinal cord injury

ObjectiveSpinal cord injury (SCI) is classified as complete or incomplete depending on the extent of sensorimotor preservation below the injury level. However, individuals with complete SCIs can voluntarily activate paralyzed lower limb muscles alone or by engaging non-paralyzed muscles during neurophysiological assessments, indicating presence of residual pathways across the injury. However, similar phenomena have not been explored for the upper extremity (UE) muscles following cervical SCIs. MethodsEighteen individuals with motor complete cervical SCI (AIS A or B) and five age-matched non-injured (NI) individuals performed various UE events against manual resistance during functional neurophysiological assessment (FNPA), and electromyographic (EMG) activity was recorded from UE muscles. ResultsOur findings demonstrated i) voluntary activation of clinically paralyzed muscles as evident from EMG readouts, ii) increased activity in these muscles during events engaging muscles above the injury level, iii) reduced spectral properties of paralyzed muscles in SCI compared to NI participants. ConclusionsFunctional EMG activity in clinically paralyzed muscles indicate presence of residual pathways across the injury establishing supralesional control over the sublesional neural circuitry. SignificanceThe findings may help explain the neurophysiological basis for UE recovery and can be exploited in designing rehabilitation techniques to facilitate UE recovery following cervical SCIs.

Convergence of Artificial Intelligence and Neuroscience towards the Diagnosis of Neurological Disorders-A Scoping Review.

Artificial intelligence (AI) is a field of computer science that deals with the simulation of human intelligence using machines so that such machines gain problem-solving and decision-making capabilities similar to that of the human brain. Neuroscience is the scientific study of the struczture and cognitive functions of the brain. Neuroscience and AI are mutually interrelated. These two fields help each other in their advancements. The theory of neuroscience has brought many distinct improvisations into the AI field. The biological neural network has led to the realization of complex deep neural network architectures that are used to develop versatile applications, such as text processing, speech recognition, object detection, etc. Additionally, neuroscience helps to validate the existing AI-based models. Reinforcement learning in humans and animals has inspired computer scientists to develop algorithms for reinforcement learning in artificial systems, which enables those systems to learn complex strategies without explicit instruction. Such learning helps in building complex applications, like robot-based surgery, autonomous vehicles, gaming applications, etc. In turn, with its ability to intelligently analyze complex data and extract hidden patterns, AI fits as a perfect choice for analyzing neuroscience data that are very complex. Large-scale AI-based simulations help neuroscientists test their hypotheses. Through an interface with the brain, an AI-based system can extract the brain signals and commands that are generated according to the signals. These commands are fed into devices, such as a robotic arm, which helps in the movement of paralyzed muscles or other human parts. AI has several use cases in analyzing neuroimaging data and reducing the workload of radiologists. The study of neuroscience helps in the early detection and diagnosis of neurological disorders. In the same way, AI can effectively be applied to the prediction and detection of neurological disorders. Thus, in this paper, a scoping review has been carried out on the mutual relationship between AI and neuroscience, emphasizing the convergence between AI and neuroscience in order to detect and predict various neurological disorders.

An Enhanced Model Free Adaptive Control Approach for Functional Electrical Stimulation Assisted Knee Joint Regulation and Control.

Functional electrical stimulation has been widely used in the neurologically disabled population as a rehabilitation method because of its intrinsic and higher ability to activate paralyzed muscles. However, the nonlinear and time-varying nature of the muscle against exogenous electrical stimulus makes it very challenging to achieve optimal control solutions in real-time, that results in difficulty in achieving functional electrical stimulus-assisted limb movement control in the real-time rehabilitation process. Model-based control methods have been suggested in many functional electrical stimulations elicited limb movement applications. However, in the presence of uncertainties and dynamic variations during the process the model-based control methods are unable to give a robust performance. In this work, a model-free adaptable control approach is designed to regulate knee joint movement with electrical stimulus assistance without prior knowledge of the dynamics of the subjects. The model free adaptive control with a data-driven approach is provided with recursive feasibility, compliance with input constraints, and exponential stability. The experimental results obtained from both able-bodied participants and a participant with spinal cord injury validate the ability of the proposed controller to allocate electrical stimulus for regulating seated knee joint movement in the pre-defined trajectory.

Exercise Training Does Not Attenuate Cardiac Atrophy or Loss of Function in Individuals With Acute Spinal Cord Injury: A Pilot Study

ObjectiveTo investigate the effects of 2 modes of exercise training, upper-body alone, and the addition of electrical stimulation of the lower body, to attenuate cardiac atrophy and loss of function in individuals with acute spinal cord injury (SCI). DesignRandomized controlled trial. SettingRehabilitation Hospital. ParticipantsVolunteers (N=27; 5 women, 22 men) who were <24 months post SCI. InterventionsVolunteers completed either 6 months of no structured exercise (Control), arm rowing (AO), or a combination of arm rowing with electrical stimulation of lower body paralyzed muscle (functional electrical stimulation [FES] rowing). Main Outcome MeasuresTransthoracic echocardiography was performed on each subject prior to and 6 months after the intervention. The relations between time since injury and exercise type to cardiac structure and function were assessed via 2-way repeated-measures analysis of variance and with multilevel linear regression. ResultsTime since injury was significantly associated with a continuous decline in cardiac structure and systolic function, specifically, a reduction in left ventricular mass (0.197 g/month; P=.049), internal diameter during systole (0.255 mm/month; P<.001), and diastole (0.217 mm/month; P=.019), as well as cardiac output (0.048 L/month, P=.019), and left ventricular percent shortening (0.256 %/month; P=.027). These associations were not differentially affected by exercise (Control vs AO vs FES, P>.05). ConclusionsThese results indicate that within the subacute phase of recovery from SCI there is a linear loss of left ventricular cardiac structure and systolic function that is not attenuated by current rehabilitative aerobic exercise practices. Reductions in cardiac structure and function may increase the risk of cardiovascular disease in individuals with SCI and warrants further interventions to prevent cardiac decline.

Facilitation of dependent transfers with functional neuromuscular stimulation: a computer simulation study.

A two-part simulation process was developed to investigate the facilitation of vertical patient lifts with functional neuromuscular stimulation (FNS) in individuals with spinal cord injury (SCI). First, external lifting forces representing caregiver assistance were applied to a 3D musculoskeletal model representing the patient and optimized to enforce a specific lifting trajectory during a forward dynamic simulation. The process was repeated with and without the activation of the knee, hip, and trunk extensor muscles of the patient model to represent contractions of the paralyzed muscles generated via FNS. Secondly, the spinal compression experienced by a caregiver at the L5/S1 joint while generating these external lifting forces was estimated using a second musculoskeletal model representing the caregiver. Simulation without muscle activation predicted spinal compression in the caregiver model approximately 1.3 × the National Institute for Occupational Safety and Health (NIOSH) recommended "Action Limit." Comparatively, simulations with two unique patterns of muscle activation both predicted caregiver spinal compressions below NIOSH recommendations. These simulation results support the hypothesis that FNS activation of a patient's otherwise paralyzed muscles would lower the force output required of a caregiver during a dependent transfer, thus lowering the spinal compression and risk of injury experienced by a caregiver.