We thank Anniwaer Yilifate for proofreading our manuscript. This study was supported by the National Science Foundation under Grant No. 81902281 and No. 82072544, the General Guidance Project of Guangzhou Health and Family Planning Commission under Grant No. 20191A011091 and No. 20211A011106, the Guangzhou Key Laboratory Fund under Grant No. 201905010004 and Guangdong Basic and Applied Basic Research Foundation under Grant No.2020A1515010578.

NOTE: The clinical study was approved by the Medical Ethics Association of the Fifth Affiliated Hospital of Guangzhou Medical University (NO. KY01-2019-02-27) and has been registered at the China Clinical Trial Registration Center (No. ChiCTR1800017487 and entitled, &#34;The multiple modal tasks on gait control and motor cognition after stroke&#34;).
1. Recruitment
<ol>
	<li>Recruit stroke patients with the following inclusion criteria: patients meeting the diagnostic criteria for cerebrovascular disease of the Neurological Branch of the Chinese Medical Association (2005); cerebral infarction confirmed by computed tomography or magnetic resonance imaging; damage to the unilateral cortex or with a subcortical lesion; ability to walk independently, Brunnstrom stage &#8805; 4 stages; Modified Ashworth Scale11&#160;&#8804; 2 points; meeting the requirements of three-dimensional (3D) gait analysis and the ability to tolerate the whole process; and the ability to give informed consent.</li>
	<li>Ensure the following exclusion criteria are met: congestive heart failure, deep vein thrombosis of the lower extremities, malignant progressive hypertension, respiratory failure or other diseases, and serious risk of falling.</li>
	<li>Obtain written informed consent from all patients before beginning the study.</li>
</ol>
2. Clinical evaluation
<ol>
	<li>Record the demographic characteristics of the patient including the name, gender, date of birth, level of education, chief complaint, current medical history, past history, medical treatment, and current medications.</li>
	<li>Cognitive function assessment
	<ol>
		<li>Ask the patient to complete the Mini-Mental State Examination (MMSE)12 record the patient&#39;s responses to a 30-question scale with a total score of 30 points for cognition evaluation, which involves the following seven aspects: time orientation, position orientation, instant memory, attention and computing power, delayed memory, language, and visual space. 
		&#8203;NOTE: The scores of MMSE are closely related to the level of education. The normal cognitive standard is illiteracy &#62; 17 points, primary school &#62; 20 points, and junior high school &#62; 24 points13.</li>
		<li>Ask the patient to complete the Montreal Cognitive Assessment (MoCA)14 record the patient&#39;s responses to an 11-question scale with a total score of 30 points for cognition evaluation, which involves the following eight aspects: attention and concentration, executive function, memory, language, visual structure skills, abstract thinking, calculation, and orientation. 
		&#8203;NOTE: The normal cognitive standard is &#8805; 26 points. If the subject has been educated for less than 12 years, they should add 1 point to the score15.</li>
	</ol>
	</li>
	<li>Walking ability assessment
	<ol>
		<li>Conduct the 10-m walk test (10 MWT)16. Ask the patient to perform three consecutive trials at a self-selected pace for safety, comfort, and higher speed, respectively. Record the time taken to walk to the middle 6 m in each trial (to exclude acceleration and deceleration effects).</li>
		<li>Conduct the timed up and go test (TUGT)17. Ask the patient to perform three consecutive TUG trials (stand up, walk 3 m, turn, walk back, and sit down) at a self-selected pace for safety and comfort18.</li>
	</ol>
	</li>
</ol>
3. 3D gait analysis
<ol>
	<li>Patient preparation
	<ol>
		<li>Inform the patient about the precautions and the purpose of the experiment.</li>
		<li>Ask the patient to wear tight underwear to fully expose the neck, shoulders, waist, and lower limbs.</li>
		<li>Record the values of various anthropometric indicators including height, weight, bilateral width of the ankle joints, bilateral knee diameter, pelvic width, bilateral pelvic depth, and bilateral leg length.</li>
		<li>Place 22 markers on key points of the patient based on the Davis protocol19: three markers on the trunk (7th cervical vertebrae, shoulders on both sides); three markers on the pelvis (both sides of the anterior superior iliac spine&#160;and ankle joint); six markers on the thigh (bilateral femoral greater trochanter, femoral condyle, and middle point of femoral greater trochanter and femoral condyle on the same side); six markers on the calf (bilateral humeral head, lateral ankle joint, and middle point of humeral head and lateral ankle joint on the same side); four markers on the foot (the fifth metatarsal head and the heel on both sides) (Figure 1).</li>
		<li>Click on the Start button of the 3D gait analysis system, and make a new profile for the patient.</li>
		<li>Enter basic patient information and previously measured parameters.</li>
	</ol>
	</li>
	<li>Standing data acquisition
	<ol>
		<li>Instruct the patient to maintain an upright position on the force plate for at least 3-5 s to gather the baseline data.</li>
		<li>Click on the Proc_Davis_Standing button to quickly check the position of the marker.</li>
	</ol>
	</li>
	<li>Walking task data acquisition
	<ol>
		<li>Determine the random order of three walking tasks by drawing lots.</li>
		<li>Ask the patient to walk on the walking pass for five trials at a self-selected comfortable speed, which is marked as Task 0 (consider the single walking task as the Baseline task).</li>
		<li>Ask the patient to walk while holding a bottle of water on the walking pass for five trials at a self-selected comfortable speed, which is marked as Task 1 (simple dual-motor task). 
		NOTE: Ask the patient to hold a 550 mL bottle of water in the unaffected hand while holding the arm position of the shoulder joint at 0&#176; and elbow flexion at 90&#176;.</li>
		<li>Ask the patient to walk across the line in the middle of the walking pass for five trials at a self-selected comfortable speed, which is marked as Task 2 (complex dual-motor task). 
		&#8203;NOTE: Place a soft ruler in the middle of the walking pass before Task 2 data acquisition.</li>
	</ol>
	</li>
</ol>
4. Data processing and analysis
<ol>
	<li>Select the middle three trials of each walking task to be processed to ensure the patient is stable.</li>
	<li>Identify each gait cycle with two consecutive heel stride points on the same side.</li>
	<li>Mark the toe-off point in each gait cycle20.</li>
	<li>Click on the Proc_DavisHeel+GI_AE button to compute the kinematic parameters of gait, as well as the computation of the Gait Performance Score (GPS) index.</li>
</ol>
5. Data extraction and statistical analysis of interest
<ol>
	<li>Select region of interest parameters from the processed data, which include special-temporary parameters (stance phase, swing phase, single stance, double stance, cadence), joint angle parameters (trunk obliquity (frontal plane), trunk tilt (sagittal plane), trunk rotation (transversal plane), pelvic obliquity (frontal plane), pelvic tilt (sagittal plane), pelvic rotation (transversal plane), hip flex-extension, hip ab-adduction, hip rotation, knee flex-extension, ankle dorsi-plantarflexion, and GPS index.</li>
	<li>Calculate DTC values based on the following formula[10]: 
	([single-task gait velocity - dual-task gait velocity]/ single-task gait velocity) &#215; 100 (1)</li>
	<li>Perform the statistical analysis (see the Table of Materials) using the methodology described previously20,21.
	<ol>
		<li>Present parametric data as means and standard deviation if normally distributed or as medians if not.</li>
		<li>Use the paired t-test to compare the differences in kinematic parameters between patients in Task 1 and Task 2 conditions.</li>
		<li>Use one-way analysis of variance to compare three different tasks (Task 0, Task 1, and Task 2) of the kinematic parameters. Set statistical significance at P &#60; 0.05.</li>
	</ol>
	</li>
</ol>

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</ol>

The authors have nothing to disclose.

This study describes a protocol for the clinical assessment of dual motor task gait analysis in stroke patients with motor control deficits. The design of this protocol was based on two main points. First, most previous studies used a single walking task to assess the gait function of stroke patients, and the related discussions on motor control were inadequate, especially because the principles of complex motor movements were rarely involved22,23. Therefore, in this study, in addition to the single walking task as the baseline, the authors mainly focused on the comparison of two dual-tasks of motor performance and walking, including the task of water-holding (simple motor dual-task) and the task of crossing obstacles (complex motor dual-task)24. The water-holding task was identified as being equivalent to a combination of a simple walking task and a simple motor task.
Because the cross-obstacle walking task involvedmore nervous system, skeletal muscle movement, and cognitive resources in participating in motor control (including motor planning, motor coordination, and motor feedback) than the simple motor dual-task of holding water while walking, it was identified as being equivalent to a combination of a simple walking task and a complex motor task. Thus, the motor control function deficit after stroke could be closely examined based on this experimental task design. Previous dual-task gait analyses in the elderly and in patients with cognitive impairment have reported decreased velocity and cadence in dual-task walking compared with single-task walking25.
However, the results of this study in stroke patients show that there were no significant differences in spatiotemporal parameters in dual motor tasks compared with those of the single motor task. The major changes were only observed in the proximal joint angles, especially the angles of the trunk, pelvis, and hip joints, which were significantly larger in dual motor tasks than in single walking tasks. This might be related to the obvious motor deficit of recruited stroke patients compared with the elderly or cognitively impaired patients (their basic motor function is preserved). There might be similar difficulties while performing a simple motor task and a complex motor task in stroke patients with existing impaired motor function, which could explain why the spatiotemporal parameters and distal joint angle were not sensitive parameters for the comparison between single and dual motor tasks in stroke patients. Additionally, these results suggest that rehabilitation training to increase trunk and large joint control might help stroke patients improve their ability to perform complex daily motor activities.
The heterogeneity of stroke patients has always been the main obstacle in many investigations26. A previous study had explored the use of the DTC value (the dual-task consumption ratio as the difference between a single task and double tasks) to eliminate the heterogeneity between stroke patients10. Indeed, the representative results demonstrate that the bilateral joint angle parameters of the large proximal joints in the complex dual walking task are significantly larger than those in the simple motor dual-task, indicating the advantages of using the DTC values in dual-task gait assessment for stroke patients.
This study has three main limitations. First, as this study is mainly a methodological demonstration of dual-motor tasks, the representative data only included data of 18 male stroke patients. In addition, previous studies have suggested that both gender and age impact gait and balance function. For example, as age increases, the ability to control posture decreases, and women are more affected than men. Moreover, the lack of significant difference in spatiotemporal parameters found in this study might be simply because of the sample size. Hence, further studies are needed to increase the sample size and include female subjects to extend the clinical application of this assessment. In conclusion, through dual-motor walking tasks and the calculation of DTC values, this research protocol aims to provide a basis for the clinical diagnosis of gait function and an in-depth study of motor control in stroke patients.

The restoration of independent walking function is one of the requisites for the participation of post-stroke patients in community life1. The recovery of walking ability requires not only the interaction of the perception and cognitive systems, but also motor control2,3,4. Furthermore, in real community life, people require higher abilities such as performing two or more tasks at the same time (e.g., walking while holding objects or crossing obstacles). Therefore, studies have begun to focus on the interference of dual-tasks in gait performance5,6. Previous dual-task studies were mostly targeted to elderly and cognitively impaired patients owing to the difficulty in motor performance and heterogeneity in stroke patients; the gait function in stroke patients was mostly evaluated by a single walking task7,8,9. However, further research on dual-task gait analysis, especially motor dual-tasks related to motor control, is required.
This study introduces a methodology for dual motor task gait analysis and evaluation. This protocol not only includes clinical assessment of the walking ability in stroke patients, but also focuses on two dual-motor tasks: the holding-water-and-walking task (a simple dual motor task) and the crossing-obstacle walking task (a complex dual motor task). The aim of this study was to explore the effects of dual motor tasks on the gait of stroke patients and to employ the dual-task gait cost (DTC) values10 of dual-task parameters (the difference between a single task and dual-task) to exclude the heterogeneity among stroke patients. The design of the experimental tasks facilitated an in-depth discussion of the motor control function of stroke patients, which provided new ideas for the clinical diagnosis and evaluation of the gait function of stroke patients.

<table><tbody><tr><td>BTS Smart DX system</td><td>Bioengineering Technology System, Milan, Italy</td><td>1</td><td>Temporospatial data collection</td></tr><tr><td>BTS SMART-Clinic software</td><td>Bioengineering Technology System, Milan, Italy</td><td>2</td><td>Data processing</td></tr><tr><td>SPSS software (version 25.0)</td><td>IBM Crop., Armonk, NY, USA</td><td></td><td>Statistical analysis</td></tr></tbody></table>

motor dual-tasks for gait analysis and evaluation in post-stroke patients

Eighteen stroke patients were recruited for this study involving the evaluation of cognition and walking ability and multitask gait analysis. Multitask gait analysis consisted of a single walking task (Task 0), a simple motor dual-task (water-holding, Task 1), and a complex motor dual-task (crossing obstacles, Task 2). The task of crossing obstacles was considered to be equivalent to the combination of a simple walking task and a complex motor task as it involved more nervous system, skeletal movement, and cognitive resources. To eliminate heterogeneity in the results of the gait analysis of the stroke patients, the dual-task gait cost values were calculated for various kinematic parameters. The major differences were observed in the proximal joint angles, especially in the angles of the trunk, pelvis, and hip joints, which were significantly larger in the dual motor tasks than in the single walking task. This research protocol aims to provide a basis for the clinical diagnosis of gait function and an in-depth study of motor control in stroke patients with motor control deficits through the analyses of dual-motor walking tasks.

Watch this Scientific Journal Video about Motor Dual-Tasks for Gait Analysis and Evaluation in Post-Stroke Patients at JoVE.com

Motor Dual-Tasks for Gait Analysis and Evaluation in Post-Stroke Patients

This paper presents a protocol specifically for dual motor task gait analysis in stroke patients with motor control deficits.

Eighteen stroke patients were recruited for this study involving the evaluation of cognition and walking ability and multitask gait analysis. Multitask ...

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2.3K Views.  The Fifth Affiliated Hospital of Guangzhou Medical University. This paper presents a protocol specifically for dual motor task gait analysis in stroke patients with motor control deficits. 

Video: Motor Dual-Tasks for Gait Analysis and Evaluation in Post-Stroke Patients

Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI

Spinal cord injury (SCI) is a debilitating disorder, which produces profound deficits in volitional motor control. Following medical stabilization, recovery from SCI typically involves long term rehabilitation. While recovery of walking ability is a primary goal in many patients early after injury, those with a motor incomplete SCI, indicating partial preservation of volitional control, may have the sufficient residual descending pathways necessary to attain this goal. However, despite physical interventions, motor impairments including weakness, and the manifestation of abnormal involuntary reflex activity, called spasticity or spasms, are thought to contribute to reduced walking recovery. Doctrinaire thought suggests that remediation of this abnormal motor reflexes associated with SCI will produce functional benefits to the patient. For example, physicians and therapists will provide specific pharmacological or physical interventions directed towards reducing spasticity or spasms, although there continues to be little empirical data suggesting that these strategies improve walking ability.
In the past few decades, accumulating data has suggested that specific neuromodulatory agents, including agents which mimic or facilitate the actions of the monoamines, including serotonin (5HT) and norepinephrine (NE), can initiate or augment walking behaviors in animal models of SCI. Interestingly, many of these agents, particularly 5HTergic agonists, can markedly increase spinal excitability, which in turn also increases reflex activity in these animals. Counterintuitive to traditional theories of recovery following human SCI, the empirical evidence from basic science experiments suggest that this reflex hyper excitability and generation of locomotor behaviors are driven in parallel by neuromodulatory inputs (5HT) and may be necessary for functional recovery following SCI. 
The application of this novel concept derived from basic scientific studies to promote recovery following human SCI would appear to be seamless, although the direct translation of the findings can be extremely challenging. Specifically, in the animal models, an implanted catheter facilitates delivery of very specific 5HT agonist compounds directly onto the spinal circuitry. The translation of this technique to humans is hindered by the lack of specific surgical techniques or available pharmacological agents directed towards 5HT receptor subtypes that are safe and effective for human clinical trials. However, oral administration of commonly available 5HTergic agents, such as selective serotonin reuptake inhibitors (SSRIs), may be a viable option to increase central 5HT concentrations in order to facilitate walking recovery in humans. Systematic quantification of how these SSRIs modulate human motor behaviors following SCI, with a specific focus on strength, reflexes, and the recovery of walking ability, are missing.
This video demonstration is a progressive attempt to systematically and quantitatively assess the modulation of reflex activity, volitional strength and ambulation following the acute oral administration of an SSRI in human SCI. Agents are applied on single days to assess the immediate effects on motor function in this patient population, with long-term studies involving repeated drug administration combined with intensive physical interventions.

This video demonstrates modulation of reflex activity, volitional strength and ambulation through clinical and quantitative assessments in individuals with motor incomplete SCI as a result of acute oral administration of a serotonin reuptake inhibitor (SSRI).

Spinal cord injury (SCI) is a debilitating disorder, which produces profound deficits in volitional motor control. Following medical stabilization, ...

Medicine

Asymmetric Walkway: A Novel Behavioral Assay for Studying Asymmetric Locomotion

Behavioral assays are commonly used for the assessment of sensorimotor impairment in the central nervous system (CNS). The most sophisticated methods for quantifying locomotor deficits in rodents is to measure minute disturbances of unconstrained gait overground (e.g., manual BBB score or automated CatWalk). However, cortical inputs are not required for the generation of basic locomotion produced by the spinal central pattern generator (CPG). Thus, unconstrained walking tasks test locomotor deficits due to motor cortical impairment only indirectly. In this study, we propose a novel, precise foot-placement locomotor task that evaluates cortical inputs to the spinal CPG. An instrumented peg-way was used to impose symmetrical and asymmetrical locomotor tasks mimicking lateralized movement deficits. We demonstrate that shifts from equidistant inter-stride lengths of 20% produce changes in the forelimb stance phase characteristics during locomotion with preferred stride length. Furthermore, we propose that the asymmetric walkway allows for measurements of behavioral outcomes produced by cortical control signals. These measures are relevant for the assessment of impairment after cortical damage.

Here, we present a protocol to quantify precise stepping in rodents. Cortical and the spinal central pattern generator signals are required for precise foot-placement during obstructed locomotion. We report here the novel constrained walking task that directly examines precise stepping behavior.

Behavioral assays are commonly used for the assessment of sensorimotor impairment in the central nervous system (CNS). The most sophisticated methods for ...

Behavior

Standing Neurophysiological Assessment of Lower Extremity Muscles Post-Stroke

Transcranial magnetic stimulation (TMS) is a common tool used to measure the behavior of motor circuits in healthy and neurologically impaired populations. TMS is used extensively to study motor control and the response to neurorehabilitation of the upper extremities. However, TMS has been less utilized in the study of lower extremity postural and walking-specific motor control. The limited use and the additional methodological challenges of lower extremity TMS assessments have contributed to the lack of consistency in lower extremity TMS procedures within the literature. Inspired by the decreased ability to record lower extremity TMS motor evoked potentials (MEP), this methodological report details steps to enable post-stroke TMS assessments in a standing posture. The standing posture allows for the activation of the neuromuscular system, reflecting a state more akin to the system's state during postural and walking tasks. Using dual-top force plates, we instructed participants to equally distribute their weight between their paretic and non-paretic legs. Visual feedback of the participants' weight distribution was provided. Using image guidance software, we delivered single TMS pulses via a double-cone coil to the participants' lesioned and non-lesioned hemispheres and measured the corticomotor response of the paretic and non-paretic tibialis anterior and soleus muscles. Performing assessments in the standing position increased the TMS response rate and allowed for the use of the lower stimulation intensities compared to the standard sitting/resting position. Utilization of this TMS protocol can provide a common approach to assess the lower extremity corticomotor response post-stroke when the neurorehabilitation of postural and gait impairments are of interest.

This protocol describes the process for performing a neurophysiological assessment of the lower extremity muscles, tibialis anterior and soleus, in a standing position using TMS in people post-stroke. This position provides a greater probability of eliciting a post-stroke TMS response and allows for the use of reduced stimulator power during neurophysiological assessments.

Transcranial magnetic stimulation (TMS) is a common tool used to measure the behavior of motor circuits in healthy and neurologically impaired ...

A Human-machine-interface Integrating Low-cost Sensors with a Neuromuscular Electrical Stimulation System for Post-stroke Balance Rehabilitation

A stroke is caused when an artery carrying blood from heart to an area in the brain bursts or a clot obstructs the blood flow to brain thereby preventing delivery of oxygen and nutrients. About half of the stroke survivors are left with some degree of disability. Innovative methodologies for restorative neurorehabilitation are urgently required to reduce long-term disability. The ability of the nervous system to reorganize its structure, function and connections as a response to intrinsic or extrinsic stimuli is called neuroplasticity. Neuroplasticity is involved in post-stroke functional disturbances, but also in rehabilitation. Beneficial neuroplastic changes may be facilitated with non-invasive electrotherapy, such as neuromuscular electrical stimulation (NMES) and sensory electrical stimulation (SES). NMES involves coordinated electrical stimulation of motor nerves and muscles to activate them with continuous short pulses of electrical current while SES involves stimulation of sensory nerves with electrical current resulting in sensations that vary from barely perceivable to highly unpleasant. Here, active cortical participation in rehabilitation procedures may be facilitated by driving the non-invasive electrotherapy with biosignals (electromyogram (EMG), electroencephalogram (EEG), electrooculogram (EOG)) that represent simultaneous active perception and volitional effort. To achieve this in a resource-poor setting, e.g., in low- and middle-income countries, we present a low-cost human-machine-interface (HMI) by leveraging recent advances in off-the-shelf video game sensor technology. In this paper, we discuss the open-source software interface that integrates low-cost off-the-shelf sensors for visual-auditory biofeedback with non-invasive electrotherapy to assist postural control during balance rehabilitation. We demonstrate the proof-of-concept on healthy volunteers.

A novel low-cost human-machine interface for interactive post-stroke balance rehabilitation system is presented in this article. The system integrates off-the-shelf low-cost sensors towards volitionally driven electrotherapy paradigm. The proof-of-concept software interface is demonstrated on healthy volunteers.

A stroke is caused when an artery carrying blood from heart to an area in the brain bursts or a clot obstructs the blood flow to brain thereby preventing ...

Home-Based Monitor for Gait and Activity Analysis

Current outcomes in neuromuscular disorder clinical trials include motor function scales, timed tests, and strength measures performed by trained clinical evaluators. These measures are slightly subjective and are performed during a visit to a clinic or hospital and constitute therefore a point assessment. Point assessments can be influenced by daily patient condition or factors such as fatigue, motivation, and intercurrent illness. To enable home-based monitoring of gait and activity, a wearable magneto-inertial sensor (WMIS) has been developed. This device is a movement monitor composed of two very light watch-like sensors and a docking station. Each sensor contains a tri-axial accelerometer, gyroscope, magnetometer, and a barometer that record linear acceleration, angular velocity, the magnetic field of the movement in all directions, and barometric altitude, respectively. The sensors can be worn on the wrist, ankle, or wheelchair to record the subject&#8217;s movements during the day. The docking station enables data uploading and recharging of sensor batteries during the night. Data are analyzed using proprietary algorithms to compute parameters representative of the type and intensity of the performed movement. This WMIS can record a set of digital biomarkers, including cumulative variables, such as total number of meters walked, and descriptive gait variables, such as the percentage of the most rapid or longest stride that represents the top performance of patient over a predefined period of time.

This innovative device uses magneto-inertial sensors to permit gait and activity analysis in uncontrolled environments. Currently in the qualification process as an outcome measure in the European Medical Agency, one of the applications will be to serve as a clinical endpoint in clinical trials in neuromuscular diseases.

Current outcomes in neuromuscular disorder clinical trials include motor function scales, timed tests, and strength measures performed by trained clinical ...

Bioengineering

Dual-Task Stroop Paradigm for Detecting Cognitive Deficits in High-Functioning Stroke Patients

General clinical cognitive assessment scales are not sensitive enough to cognitive impairment in high-functioning stroke patients. The dual-task assessment has advantages for identifying cognitive deficits in high-functioning stroke patients and has been gradually applied in clinical assessment and cognitive training. Moreover, the Stroop paradigm has higher sensitivity and specificity for attentional assessment than conventional clinical cognitive assessment scales. Therefore, this study presents the dual-task assessment based on the Stroop paradigm to identify cognitive deficits in high-functioning stroke patients. This study demonstrates a single- and dual-task evaluation based on the Stroop paradigm and confirms its feasibility through case experiments and synchronized functional near-infrared spectroscopy evaluation. The Stroop reaction time and correct rate are used as the main indicators to evaluate the cognitive level of the subjects. This study protocol aims to provide new ideas to figure out the ceiling effect in general clinical assessment failure for high-functioning stroke patients.

Clinical assessment scales are notsensitive enough to cognitive dysfunction in high-functioning stroke patients. The dual-task paradigm presents advantages and potential in the assessment and cognitive training of cognitive dysfunction. The study here proposes a dual-task Stroop paradigm to identify cognitive dysfunction in high-functioning stroke patients.

General clinical cognitive assessment scales are not sensitive enough to cognitive impairment in high-functioning stroke patients. The dual-task ...

Use of a Foot-Induced Digitally Controlled Resistance Device for Functional Magnetic Resonance Imaging Evaluation in Patients with Foot Paresis

Neurological deficits from a stroke can result in long-term motor disabilities, including those that affect walking gait. However, extensive rehabilitation following stroke is typically time limited. Establishing predictive biomarkers to identify patients who may meaningfully benefit from additional physical therapy and demonstrate improvement is important to improve the patients&#39; quality of life. Detection of neuroplastic remodeling of the affected region and changes in the activity patterns excited while performing suitable motor tasks could have valuable implications for chronic stroke recovery. This protocol describes the use of a digitally controlled, magnetic resonance-compatible foot-induced robotic device (MR_COFID) to present a personalized foot-motor task involving trajectory following to stroke-affected subjects with gait impairment during functional magnetic resonance imaging (fMRI). In the task, foot flexion is performed against bi-directional resistive forces, which are tuned to the subject&#39;s strength in both the dorsiflexion and plantar flexion directions, while following a visual metronome. fMRI non-invasively uses endogenous deoxyhemoglobin as a contrast agent to detect blood oxygenation level-dependent (BOLD) changes between the active and resting periods during testing. Repeated periodic testing can detect therapy-related changes in excitation patterns during task performance. The use of this technique provides data to identify and measure biomarkers that may indicate the likelihood of an individual benefitting from rehabilitation beyond that which is currently provided to stroke patients.

Chronic stroke patients' insured rehabilitation is generally time limited. Imaging-based study of brain activity from walking-related motor tasks can lead to establishing biomarkers to measure improved outcomes and justify extending tailored therapy. A novel, magnetic resonance-compatible, variable-resistance foot motion device and a protocol for use during functional magnetic resonance imaging are presented.

Neurological deficits from a stroke can result in long-term motor disabilities, including those that affect walking gait. However, extensive ...

Evaluating Brain Activation by fNIRS During a Lower Limb Robotic Therapy Session

An Experiment Using Functional Near-Infrared Spectroscopy and Robot-Assisted Multi-Joint Pointing Movements of the Lower Limb

Stroke affects approximately 17 million individuals worldwide each year and is a leading cause of long-term disability. Robotic therapy has shown promise in helping stroke patients regain lost motor functions. One potential avenue for increasing the understanding of how motor recovery occurs is to study brain activation during the movements that are targeted by therapy in healthy individuals. Functional Near-Infrared Spectroscopy (fNIRS) has emerged as a promising neuroimaging technique for examining neural underpinnings of motor function. This study aimed to investigate fNIRS neural correlates of complex lower limb movements in healthy subjects. Participants were asked to perform cycles of rest and movement for 6 min using a robotic device for motor rehabilitation. The task required coordinated knee and ankle joint movements to point to targets displayed on a computer screen. Two experimental conditions with different levels of movement assistance provided by the robot were explored. The results showed that the fNIRS protocol effectively detected brain regions associated with motor control during the task. Notably, all subjects exhibited greater activation in the contralateral premotor area during the no-assistance condition compared to the assisted condition. In conclusion, fNIRS appears to be a valuable approach for detecting changes in oxyhemoglobin concentration associated with multi-joint pointing movements of the lower limb. This research might contribute to the understanding of stroke motor recovery mechanisms and might pave the way for improved rehabilitation treatments for stroke patients. However, further research is needed to fully elucidate the potential of fNIRS in studying motor function and its applications in clinical settings.

Author Spotlight: Assessing Brain Activity in Robotic-Assisted Lower Limb Rehabilitation Using fNIRS

It is estimated that 1 in 6 individuals worldwide will have a stroke in their lifetime, causing long-term disability, whose rehabilitation mechanisms are still poorly understood. This study proposes a protocol to evaluate brain activation by functional near-infrared spectroscopy (fNIRS) during a lower limb robotic therapy session.

Stroke affects approximately 17 million individuals worldwide each year and is a leading cause of long-term disability. Robotic therapy has shown promise ...

Scalp Acupuncture Synchronizing Dual Task Gait for Enhancing Prefrontal Cortex Response

Studies have shown that motor-cognitive dual task can greatly improve motor/cognitive function. However, the therapeutic effect of motor-cognitive dual task is still limited. How to improve dual-task performance is the key to solving this problem. Scalp acupuncture is a non-drug intervention method of traditional Chinese medicine to treat brain-derived diseases by acupuncturing the corresponding projection area of cerebral cortex function on the scalp. Studies have shown that scalp acupuncture helps improve neuronal damage and cognitive dysfunction and plays a neuroprotective function in central nervous system diseases. However, no relevant studies have discussed the synergistic gain effect of motor-cognitive dual task and scalp acupuncture. Therefore, this protocol aims to demonstrate the standardized operation of scalp acupuncture synchronizing motor-cognitive dual task and motor-cognitive dual task and compares the differences between these two tasks in healthy subjects through a randomized cross-over trial. This protocol initially revealed the possible influence mechanism of scalp acupuncture synchronizing motor-cognitive dual task on cognitive performance, gait control, and cortical brain function, which can provide new ideas and a theoretical basis for clinical exploration of new and effective non-drug treatment of integrated Chinese and Western medicine.

This protocol demonstrates the standardized procedure of scalp acupuncture synchronizing motor-cognitive dual task and motor-cognitive dual task. This can provide an important reference for the clinical exploration of the new and effective non-drug treatment of integrated Chinese and Western medicine.

Studies have shown that motor-cognitive dual task can greatly improve motor/cognitive function. However, the therapeutic effect of motor-cognitive dual ...

Dual Upper Limb Robotic Training in Stroke Rehabilitation

Application of a Dual Upper Limb Task-Oriented Robotic System for the Functional Recovery of the Upper Limb in Stroke Patients

Highly repetitive and task-oriented training has been shown to promote the recovery of limb function in stroke patients. Additionally, bilateral arm training can help stroke survivors regain their upper limb function and improve their daily activities. The dual upper limb task-oriented robotic system is designed to assist the healthy side of the stroke patient in driving the affected side to perform bilateral arm training through the use of a robotic device. It can also guide the patient in carrying out dual upper limb coordinated movements and engage them in a task-oriented virtual game using force feedback and human-computer interaction technology. This study aimed to assess the efficacy of the system in enhancing upper limb function and activities of daily living in stroke patients. The assessment methods used included motor evoked potential (MEP), functional test for the hemiplegic upper extremity-Hong Kong (FTHUE-HK), Fugl-Meyer Assessment Upper Extremity Scale (FMA-UE), and modified Barthel index (MBI). The results of the study indicate that the dual upper limb task-oriented robotic system can significantly improve the corticospinal pathway, upper limb function, and activities of daily living in stroke patients after 6 weeks of treatment. This system can serve as an effective adjunct to upper limb functional rehabilitation in stroke survivors, reducing the dependence on rehabilitation therapists. In conclusion, the dual upper limb task-oriented robotic system provides a new strategy for post-stroke limb functional rehabilitation and holds great potential for application, as it offers certain social and financial benefits.

Author Spotlight: Enhancing Upper Limb Rehabilitation in Stroke Patients Through Advanced Robotic and Neuromodulation Technologies

This experimental protocol outlines the use of a dual upper limb task-oriented robotic system for stroke patients with upper limb dysfunction. The findings indicate that this system can significantly improve stroke patients' upper limb function and daily living activities.

Highly repetitive and task-oriented training has been shown to promote the recovery of limb function in stroke patients. Additionally, bilateral arm ...