Human Motor Function Research Articles

Basal Ganglia and Thalamic Contributions to Language Function: Insights from A Parallel Distributed Processing Perspective.

Cerebral representations are encoded as patterns of activity involving billions of neurons. Parallel distributed processing (PDP) across these neuronal populations provides the basis for a number of emergent properties: 1) processing occurs and knowledge (long term memories) is stored (as synaptic connection strengths) in exactly the same networks; 2) networks have the capacity for setting into stable attractor states corresponding to concepts, symbols, implicit rules, or data transformations; 3) networks provide the scaffold for the acquisition of knowledge but knowledge is acquired through experience; 4) PDP networks are adept at incorporating the statistical regularities of experience as well as frequency and age of acquisition effects; 5) networks enable content-addressable memory; 6) because knowledge is distributed throughout networks, they exhibit the property of graceful degradation; 7) networks intrinsically provide the capacity for inference. This paper details the features of the basal ganglia and thalamic systems (recurrent and distributed connectivity) that support PDP. The PDP lens and an understanding of the attractor trench dynamics of the basal ganglia provide a natural explanation for the peculiar dysfunctions of Parkinson's disease and the mechanisms by which dopamine deficiency is causal. The PDP lens, coupled with the fact that the basal ganglia of humans bears strong homology to the basal ganglia of lampreys and the central complex of arthropods, reveals that the fundamental function of the basal ganglia is computational and involves the reduction of the vast dimensionality of a complex multi-dimensional array of sensorimotor input into the optimal choice from a small repertoire of behavioral options - the essence of reactive intention (automatic responses to sensory input). There is strong evidence that the sensorimotor basal ganglia make no contributions to cognitive or motor function in humans but can cause serious dysfunction when pathological. It appears that humans, through the course of evolution, have developed cortical capacities (working memory and volitional and reactive attention) for managing sensory input, however complex, that obviate the need for the basal ganglia. The functions of the dorsal tier thalamus, however, even viewed with an understanding of the properties of population encoded representations, remain somewhat more obscure. Possibilities include the enabling of attractor state constellations that optimize function by taking advantage of simultaneous input from multiple cortical areas; selective engagement of cortical representations; and support of the gamma frequency synchrony that enables binding of the multiple network representations that comprise a full concept representation.

In-Robot Network Architectures for Humanoid Robots With Human Sensor and Motor Functions

The design concepts of the in-robot network (IRN) architectures of humanoid robots are proposed in this paper. First, this paper reveals the network requirements for humanoid robots to realize perception abilities and action execution abilities near those of human beings. Humanoid robots need to be equipped with many sensors to collect surrounding environmental information. It is also necessary to use many motion actuators to enhance the degree of freedom to achieve the smooth motion abilities of humans. To maintain reliable data transmission between a number of nodes, an efficient and reliable IRN architecture is needed. This paper first discusses the limitations of existing humanoid robots in the number of sensors and degrees of freedom and points out that one of the reasons for this limitation is the lack of reliable network architectures. In-vehicle networks (IVNs) and various network technologies are used. These include time-sensitive networks and control area networks (CANs) to name a few. Additionally, heterogeneous network protocols are used. IRNs also include networks of sensors and actuators with different performance parameters such as bandwidth, delay, and transmission speed. IRNs may adopt design ideas similar to those of IVNs to satisfy the network requirements for humanoids. To accomplish this, three feasible IRN architectures are proposed and analyzed. Finally, to compare and analyze the three proposed IRN architectures, this paper uses OMNeT <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">++</sup> simulation software.

Research Progress and Application Prospect of Nerve Rehabilitation by Transcranial Electrical and Magnetic Stimulation

Accidents or diseases may cause impairment or even loss of human motor function, among which stroke is a disease which is most likely to cause disability and seriously endangers social health. During recent years, as a new nerve regulation technology, non-invasive brain stimulation technology can achieve the application of nerve stimulation to the brain, induce and promote neuroplasticity and improve the excitability of cerebral cortex. Especially, transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation(TMS) have shown high therapeutic potential in motor rehabilitation. This paper summarizes the mechanism and progress of the research and application of tDCS and TMS in the field of neurorehabilitation. Its technical challenges and future development trends are provided as well.

A Taxonomy of Ethical, Legal and Social Implications of Wearable Robots: An Expert Perspective

Wearable robots and exoskeletons are relatively new technologies designed for assisting and augmenting human motor functions. Due to their different possible design applications and their intimate connection to the human body, they come with specific ethical, legal, and social issues (ELS), which have not been much explored in the recent ELS literature. This paper draws on expert consultations and a literature review to provide a taxonomy of the most important ethical, legal, and social issues of wearable robots. These issues are categorized in (1) wearable robots and the self, (2) wearable robots and the other, and (3) wearable robots in society.

Probing myelin content of the human brain with MRI: A review.

Rapid and efficient transmission of electric signals among neurons of vertebrates is ensured by myelin-insulating sheaths surrounding axons. Human cognition, sensation, and motor functions rely on the integrity of these layers, and demyelinating diseases often entail serious cognitive and physical impairments. Magnetic resonance imaging radically transformed the way these disorders are monitored, offering an irreplaceable tool to noninvasively examine the brain structure. Several advanced techniques based on MRI have been developed to provide myelin-specific contrasts and a quantitative estimation of myelin density in vivo. Here, the vast offer of acquisition strategies developed to date for this task is reviewed. Advantages and pitfalls of the different approaches are compared and discussed.

A Non-Linear Evaluation Index of Human Motor Function

A Non-Linear Evaluation Index of Human Motor Function

Brain Computer Interface

Computer Technology is advancing day by day and with that it has led to the idea of Brain Computer interaction. Modern computers are advancing parallelly to our understanding of the human brain. This paper basically deals with the technology of BCI (Brain Computer Interface) that can capture brain signals and translate these signals into commands that will allow humans to control devices just by thinking. These devices can be robots, computers or virtual reality environment. The basis of BCI is a pathway connecting the brain and an external device. The aim is to assist, augment or repair human cognitive or sensory motor function. This paper also reflects light on the application areas that BCIs help in. It contributes in medical research and neuronal rehabilitation. New companies are emerging that are developing game environments involving brain computer interface.

ACTIVITY COMMAND ENCODING OF CEREBRAL CORTEX M1-EVOKED POTENTIALS OF THE SPRAGUE DAWLEY RAT USING TIME DELAY NEURAL NETWORKS

Understanding the neurons that transmit messages in the brain while we thinking, feeling, or acting is critical for research on the causes of neurological disease and treatment strategies. This research focuses on the primary motor cortex M1 region, which is involved in human motor function as an activity command center. Understanding this region can help us to determine the mechanism of movement control by the brain, with applicability to other activity mechanisms. A time delay neural network (TDNN) is a suitable model for studying brain signals. TDNN can analyze comprehensive information for a period of successive signals, which is similar to the transmission mechanism of the M1 region. Therefore, this study used a TDNN to build a three-stage encoding system corresponding to the signal type, type arrangement, and time sequence of the brainwave signal from the M1 region and the encoded results were defined as codes, symbols, and commands, respectively. This study aimed to understand the relationship between movement and the M1 region by decoding the signal when the rat undertakes an action. First, we recorded the M1 signal from three rat action types (walk, stand up, and shift head) and performed signal processing. This included using a nonlinear energy operator to find the response points of each action signal. The signals were separated into several sections according to the response time points and independent component analysis was then used to extract the features of the signal (the signal of interest). Finally, we found 16 representative sample signals through a dynamic dimension increasing algorithm to train a three-stage TDNN. We then input the remaining feature signals of interest into the three-stage TDNN for encoding and classification. The results showed an accuracy rate for the three actions of 51.4%, 80.0%, and 54.3%, which means that it is feasible to explain the brain signal of M1 from the free-moving animal using a three-stage TDNN encoding model.

The Effects of Transcranial Electrical Stimulation on Human Motor Functions: A Comprehensive Review of Functional Neuroimaging Studies.

Transcranial electrical stimulation (tES) is a promising tool to enhance human motor skills. However, the underlying physiological mechanisms are not fully understood. On the other hand, neuroimaging modalities provide powerful tools to map some of the neurophysiological biomarkers associated with tES. Here, a comprehensive review was undertaken to summarize the neuroimaging evidence of how tES affects human motor skills. A literature search has been done on the PubMed database, and 46 relative articles were selected. After reviewing these articles, we conclude that neuroimaging techniques are feasible to be coupled with tES and offer valuable information of cortical excitability, connectivity, and oscillations regarding the effects of tES on human motor behavior. The biomarkers derived from neuroimaging could also indicate the motor performance under tES conditions. This approach could advance the understanding of tES effects on motor skill and shed light on a new generation of adaptive stimulation models.

Assessment of the influence of global and local exercises on core stabilization mechanisms: randomized controlled trial.

Over the last few years, various concepts of applying core stabilization mechanisms in the formation of human motor function have come to existence. The objective of the research was to assess the influence of two types of core stability training on deep abdominal muscle thickness and on global trunk mobility. The study involved 108 individuals divided into 3 groups: LT (local training), performing the stability training based on locally isolated work of the transversus abdominis muscle; GT (global training), performing the training based on global movement patterns; and CG (control group), who did not undergo the training. The workout programs comprised 4 weeks of the exercise, 4 times a week. The measurement of the observed muscle thickness was carried out by means of ultrasound imaging. Trunk mobility was evaluated based on the toe-touch test, as well as the measurement of lateral flexion ranges. All the measurements were performed before the workout programs, right after finishing and 2 weeks after the end of the training cycle. Both training concepts have an impact on deep abdominal muscle thickness; however, in the LT group, significant improvement was noted with regard to the transversus abdominis, whereas in the GT group the improvement concerned the external oblique muscle. Both training methods also improved trunk mobility in the sagittal and frontal plane. The results we have obtained imply that both concepts of core stability training affect the human body at a structural as well as functional level. The application of the described training methods may not only provide measurable benefits in the field of clinical physiotherapy, for instance in the treatment of spine-related back pain, but also in motor training designed to improve athletes' performance and to minimize the risk of injury.

Three-Dimensional Pattern Features in Finger Tapping Test for Patients with Parkinson's disease.

Finger tapping test is an important neuropsychological test to evaluate human motor function. Most recent researches simplified the finger tapping motion as a scissors-like motion, though the rotation axis of the thumb was different from that of the forefinger. In this paper, we proposed a three-dimensional (3-D) finger tapping measurement system to obtain 3-D pattern features in finger tapping test for patients with Parkinson's disease (PD). The proposed system collected the motion of the thumb and the forefinger by nine-degrees-freedom sensors and calculated 3-D motion of finger tapping by an orientation estimation method and a 3-D finger-tapping kinematic model. We further extracted 3-D pattern features, i.e. motor coordination and relative thumb motion, from 3-D Finger Tapping motion. Moreover, we used the proposed system to collect the finger-tapping motion of 43 PD patients and 30 healthy controls in horizontal tasks and vertical tasks. The results indicated that 3-D pattern features showed a better performance than one-dimensional features in the identification of mild PD patients.Clinical Relevance- These three-dimensional pattern features could be used to evaluate finger tapping motion in a novel way, which could be used to better identify mild Parkinson's disease patients. Furthermore, the results showed that a combination of horizontal tasks and vertical tasks might be a better way to identify mild Parkinson's disease patients.

Influence of sildenafil on esophageal motor function in humans: Studies using high-resolution manometry.

Sildenafil induces smooth muscle relaxation of the esophagus by blocking type 5 phosphodiesterase that degrades cyclic guanine monophosphate. We aimed to characterize the effects of sildenafil on esophageal peristalsis and contraction reserve using high-resolution manometry (HRM). Fifteen healthy adults (12 men, age 21-39, mean 27years) participated in this study using HRM following either sildenafil 50mg or placebo. HRM with ten wet swallows and five multiple rapid swallows was performed in all participants. HRM metrics included esophagogastric junction contractile integral (EGJ-CI), basal lower esophageal sphincter (LES) pressure, 4-second integrated relaxation pressure (IRP-4s), distal contractile integral (DCI), distal latency, resting upper esophageal sphincter pressure (UESP), and the response to MRS. Sildenafil significantly lowered EGJ-CI (P<.001), LES pressure (P=.04), IRP-4s (P=.02), and DCI (P<.001). There was no difference in UESP (P=.87) between sildenafil and placebo. Sildenafil significantly decreased peristaltic vigor, inducing absent peristalsis in 12 subjects and ineffective esophageal motility in 3 subjects. Peristaltic response and augmentation following MRS were significantly inhibited following sildenafil (7% vs 100%, P<.001, and none vs 73%, P<.001). Sildenafil attenuates EGJ barrier function, resting LES pressure, and LES relaxation. Both esophageal body contractility and contraction reserve are inhibited by sildenafil in healthy adults.

DIAGNOSTICS OF HUMAN MOTOR FUNCTION IN PHYSICAL REHABILITATION

Аbstract. The use ofbiomechanical video computer analysis technology is effective for diagnosing human motor disorders. Most computer programs used in physical rehabilitation are the means of automating the calculation of physical indices, while the problem of developing application software for computerized measurement systems for rapid and objective analysis of human motor actions remains relevant. Objective. Develop software for biomechanical video-computer analysis of human motor function in physical rehabilitation. Methods. Biomechanical video-computer analysis of kinematic characteristics of human motor actions. Results. The «BioVideo» application software, which includes four modules has been developed: 1) designing models of human locomotorium; 2) determining the coordinates of points relative to the somatic frame of reference; 3) calculation of biomechanical characteristics of motor action (software capabilities of the module allow to calculate the localization of the centers of mass of biolinks and the total center of mass of the human body); 4) construction of a biokinematic scheme of the human body according to the videogram of motor actions with determination of trajectories of the centers of joints, centers of masses of biolinks and the general center of masses of a human body. The following biomechanical characteristics are determined in frame-by-frame and phase analyzes: horizontal, vertical and resulting linear velocities of the general center of mass and centers of mass of joints of the human body; the amplitude of the angles of the joints and the angular velocity of the biolinks of the athlete’s body; time characteristics; potential, kinetic, total energy of individual biolinks and the whole human body. The «BioVideo» software is designed to obtain qualitative and quantitative information about human motor function, which is the basis for the development of rehabilitation programs. The effectiveness of the developed software «BioVideo» in the diagnosis of human motor function has been confirmed by clinical studies

Human Brain Imbued Higher Brain Centre Activated Robot

Brain Computer Interface (BCI) Systems give venue for human brain to communicate with an external device via a non-physiological path. It replaces the use of nerves and muscles of the human brain with a combination of hardware and software, which translates electrophysiological signals into physical actions. It differs from neuro-modulation in that it allows for bidirectional information flow. These are often directed at researching, mapping, assisting, augmenting, or repairing human cognitive or sensory motor function. From initial demonstrations of electroencephalography-based spelling and single-neuron based device control, researchers have gone on to use electroencephalographic, intra-cortical, electro-corticographic and other brain signals for increasingly complex control of cursors, robotic arms, prosthetics, wheelchairs, and other devices related to rehabilitation engineering. Automated devices obviously can acquire intelligence and may also work similarly or differently to tackle wide range of tasks. But there is no automated robotic device available which is having enough intelligence to replicate itself. Generally the brain signal is received by electrodes placed on the scalp and is converted into programmed codes and then translated into commands that can control an output device, such as a spelling program, a motorized wheelchair, or a prosthetic limb. Feedback from the device can enable the user to modify their brain signals in order to maintain the performance of the automated device in a much more efficient manner. If those decoded codes (signals) coming from the subjects’ brain could be applied as inbuilt program of an artificial intelligence robot, then that robot might behave in a way as the subject with respect to his/her brain function. This paper has the objective to design and develop a higher brain centre activated robot that is still not available.

Human motor function estimation based on EMG signal fractal dimension standard deviation

Wearable robots must adjust the assist mode/intensity according to human motion during the motion assistance process. By decoding the surface electromyography (sEMG) signal, the standard deviation of the fractal dimension is used as a characteristic index of muscle contraction-relaxation ability, and explore the feasibility of using the standard deviation of the fractal dimension to estimate the human motor function and thus provide a basis for decision-making for the flexible control of wearable robots. First, the sEMG signals of several subjects with different motor functions were collected and their time-domain and frequency-domain features were extracted. The experimental results for one hour of walking showed that the time-domain and frequency-domain feature values increased with muscle fatigue. The trend has little to do with the inherent motor function of the human body; Second, due to the strong nonlinearity, time-varying, and strong complexity of the sEMG signal, the fractal dimension nonlinear method is used to characterize the complexity of the EMG signal that is closely related to muscle function. Besides, theoretical and experimental studies have been conducted to clarify the feasibility of the complexity of fractal dimension representation and to provide theoretical support for the further use of the standard deviation of fractal dimension to estimate human motor function. The experimental results of continuous walking for one hour show that, macroscopically, the fractal dimension of each muscle of the individual subject does not change significantly with walking time, which shows that the fractal dimension has nothing to do with exercise time and muscle fatigue; On the microscopic level, the value of the fractal dimension changes when the subject’s muscles contract and relax. Subjects with strong motor function have smaller fractal dimensions when their muscles contract than subjects with weaker motor function, and the opposite happens when their muscles relax, and it can be seen that there is a positive correlation between the difference in the fractal dimension during muscle contraction and relaxation and the muscle contraction-relaxation ability and the human body’s inherent motor function. The test results verify the feasibility of using the standard deviation of fractal dimension to estimate the intrinsic motor function of the human body.

COMPUTER MOTORICS CONTROL SYSTEMS IN PHYSICAL EDUCATION OF SCHOOLCHILDREN WITH HEARING DEPRIVATION

The analysis of scientific and methodological literature showed that the practice of adaptive physical education in specialized schools requires computer technology to control children’s motorics, as physical education can succeed only in the case of individualization, strict adequacy of personal and functional characteristics of a child with disabilities. The purpose of the study is to develop software for computer monitoring of motorics of primary school children with hearing impairments. Material and methods: generalization of data of scientific and methodical literature and experience of best practice, biomechanical video computer analysis, pedagogical testing, pedagogical experiment, methods of mathematical statistics. Testing of biomechanical characteristics of 59 schoolchildren of 7–10 years of Kyiv special boarding school № 9 for children with hearing impairment and 111 healthy children of 7–10 years of Kyiv secondary school № 229 was carried out. “BioVideo” software was developed to determine the biomechanical characteristics of human motor function based on the registration (video recording) of motor action by a digital camera. The “BioVideo” software is designed to obtain kinematic and dynamic characteristics, as well as to build biokinematical schemes of motor actions of junior schoolchildren with hearing deprivation according to the videogram. Biomechanical phase analysis of biokinematical characteristics of the even-rhythmic test exercise in the frontal plane, performed with the help of “BioVideo” software, allowed to quantify such relatively independent types of coordination abilities as sense of rhythm and orientation in junior schoolchildren with hearing deprivation. The use of software for computer monitoring of motorics of primary school children with hearing deprivation is substantiated, which allows to carry out objective control of their physical development and physical fitness, based on the results to intensify the process of physical education, differentiate and individualize physical education programs, automate analysis and evaluation received data.

1209 Effect of Secretin on Gastric Accommodation, Emptying, and Symptoms in Functional Dyspepsia and Health: A Randomized, Controlled, Cross-Over Trial

INTRODUCTION: Reduced gastric accommodation (GA) or accelerated or delayed gastric emptying (GE) contributes to pathophysiology in functional dyspepsia (FD). Secretin is an endogenous hormone secreted postprandially from the duodenal mucosa. Our objective was to determine the effects of secretin in human gastric motor functions and satiation in health and FD. METHODS: We conducted a double-blind, randomized, placebo-controlled, cross-over trial in 10 healthy participants and 10 patients with FD by Rome IV criteria. Subjects were randomized to IV secretin or normal saline with a 1-4 week washout period. We measured GA using validated 99mTc-single photon emission computed tomography with a standardized 300 mL meal of 111In radiolabeled Ensure®. We measured GE using scintigraphy of the same meal and symptoms 30 minutes post meal based on 100 mm visualized analog scale (VAS). To measure volume to fullness (VTF) and maximum tolerated volume (MTV), we performed Ensure® nutrient drink test (NDT) and recorded symptoms 30 min post-MTV. Wilcoxon Signed-Rank Test was used for comparison within healthy and FD groups and ANCOVA modeling was used for intention to treat comparison between groups, adjusting for age, sex, and treatment arm (secretin vs. placebo). Study drug was provided by ChiroClin, Inc. RESULTS: The median age for healthy volunteers (HV) was 45.0 years [IQR: 38.0, 49.0 (80% female)] and for FD was 50.5 years [42.0, 55.0 (70% female)]. There was no statistical difference in either group for secretin vs. placebo for GA. Secretin delayed GE in both HV and FD (Table 1). There was decrease in GE for secretin vs. placebo in HV at 20 minutes [-10% (-13, -7), P = 0.008] and 30 minutes [-11% (-16, -4), P = 0.004]. This finding was also seen in the FD group for GE at 25 minutes [-5% (-9, 0), P = 0.047] and 30 minutes [-8% (-9, 0), P = 0.03]. There were no statistically significant differences between treatment arms for VTF or MTV in either HV or FD. On ANCOVA analysis, there were statistically significant increases in nausea at 30 minutes (P = 0.0016) and fullness at 30 minutes (P = 0.0002) for secretin vs. placebo in FD compared to HV. CONCLUSION: Secretin delayed GE in both healthy volunteers and FD without significantly altering GA, VTF, or MTV. Secretin receptor stimulation deserves further study in FD patients with accelerated GE.

Comparison of Single‐bout AIH Protocols That Differ in Timing and Number of Hypoxic Episodes on Improvement in LUT Function in Adult Rats with SCI

Exposure to acute intermittent hypoxia (AIH) has been reported to improve respiratory and non‐respiratory somatic motor function in rodents and humans, and as such has been proposed as a potential therapeutic intervention for treatment of motor incomplete spinal cord injury (SCI). In our previous studies in rats with moderate mid‐thoracic (T8) SCI, we observed that a single bout of AIH produces sustained improvements in lower urinary tract (LUT) function characterized by decreased non‐voiding bladder contractions and increased void volume. In the present study, we extend these observations on lower LUT function in SCI rats by comparing the potential therapeutic benefits of different single‐bout AIH protocols that keep the total duration of hypoxia (15 min; 12% O2) constant but differ in timing and number of hypoxic episodes. To this end, four weeks after moderate contusion (200 kilodynes) mid‐thoracic SCI, bladder intravesical pressure was recorded in urethane‐anesthetized (1.4 g/kg), spontaneously breathing, vagally intact adult female Sprague‐Dawley rats (n = 44) during continuous infusion of saline (0.04 ml/min) into the bladder to elicit reflex micturition events. Following &gt;60 min of baseline recording, rats were exposed to a single bout of AIH consisting of (1) three 5‐min episodes of hypoxia each separated by 5‐min exposures to room air, (2) five 3‐min episodes of hypoxia each separated by 3‐min exposures to room air, or (3) ten 1.5‐min episodes of hypoxia each separated by 1.5‐min exposures to room air. Following completion of the AIH exposure protocol, data acquisition continued for up to 120 minutes while the rats continued to breathe room air, and these data were quantified based on features measured in 30‐min bins (post‐AIH data normalized to pre‐AIH data). These analyses revealed that each of the single‐bout AIH protocols elicited long‐lasting improvements (up to 120 min post‐AIH) in LUT function. Moreover, each of the protocols appeared to be equally effective in reducing the ratio of non‐voiding/voiding bladder contractions and increasing bladder inter‐contraction interval and micturition volume. Single‐bout AIH exposure also produced transient increases in both bladder contraction threshold pressure and minimum bladder pressure. Modulation of LUT behavior during individual exposures to hypoxia and immediately following each hypoxic episode (“off effect”) were also observed, with the intensity of the “off effect” tending to be lower following short duration (e.g., 10 × 1.5‐min) hypoxic exposures. Our observations suggest that each single‐bout AIH protocol is effective in reducing non‐voiding bladder contractions and increasing micturition in SCI rats albeit subtle differences in magnitude and/or timing were noted across the protocols. These data also provide additional evidence that single‐bout AIH exposure reduces bladder overactivity and stabilizes bladder function to improve voiding efficiency in SCI rats.Support or Funding InformationDOD CDMRP W81XWH‐17‐1‐0260; NYS DOH SCIRB C32088GGThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Effect of Pancreatic Polypeptide on Gastric Motor Function and Food Intake in Humans

Effect of Pancreatic Polypeptide on Gastric Motor Function and Food Intake in Humans

Functional magnetic resonance imaging of human motor unit fasciculation in amyotrophic lateral sclerosis.

A novel diffusion-weighted magnetic resonance imaging protocol sensitive to contraction of individual skeletal motor units was developed. We applied this technique to the lower limb muscles of 4 patients with confirmed amyotrophic lateral sclerosis (ALS) and 6 healthy controls. A 3-minute scan revealed florid fasciculation in ALS patients, involving both superficial and deep muscles, and at a frequency higher than in healthy controls. This novel imaging technique reveals hitherto unobtainable information on human motor unit structure and function, which may allow earlier diagnosis and recruitment to clinical trials. ANN NEUROL 2019;85:455-459.