Posts Tagged motor control

[ARTICLE] Brain oscillatory activity as a biomarker of motor recovery in chronic stroke – Full Text

Abstract

In the present work, we investigated the relationship of oscillatory sensorimotor brain activity to motor recovery. The neurophysiological data of 30 chronic stroke patients with severe upper‐limb paralysis are the basis of the observational study presented here. These patients underwent an intervention including movement training based on combined brain–machine interfaces and physiotherapy of several weeks recorded in a double‐blinded randomized clinical trial. We analyzed the alpha oscillations over the motor cortex of 22 of these patients employing multilevel linear predictive modeling. We identified a significant correlation between the evolution of the alpha desynchronization during rehabilitative intervention and clinical improvement. Moreover, we observed that the initial alpha desynchronization conditions its modulation during intervention: Patients showing a strong alpha desynchronization at the beginning of the training improved if they increased their alpha desynchronization. Patients showing a small alpha desynchronization at initial training stages improved if they decreased it further on both hemispheres. In all patients, a progressive shift of desynchronization toward the ipsilesional hemisphere correlates significantly with clinical improvement regardless of lesion location. The results indicate that initial alpha desynchronization might be key for stratification of patients undergoing BMI interventions and that its interhemispheric balance plays an important role in motor recovery.

1 INTRODUCTION

Stroke is a major global health problem. The number of stroke victims has been rising in the past years all around the world. Millions of stroke survivors are left with very limited motor function or complete paralysis and depend on assistance (Feigin et al., 2016). Therapeutic approaches such as constraint‐induced movement therapy are not applicable to the group of patients with severe limb weakness (Birbaumer, Ramos‐Murguialday, & Cohen, 2008). However, brain–machine interface (BMI) training has demonstrated efficacy in promoting motor recovery in chronic paralyzed stroke patients (Ramos‐Murguialday et al., 2013), and long term effects (Ramos‐Murguialday et al., 2019). Subsequent work has replicated and confirmed BMI efficacy. Arm and hand movements are trained using a body actuator (e.g., orthotic robots) that is controlled by oscillatory activity of the brain (Ang et al., 2014; Frolov et al., 2017; Kim, Kim, & Lee, 2016; Leeb et al., 2016; Mokienko et al., 2016; Ono et al., 2014). Brain signals can thus travel to the limb muscles along an alternative pathway. Contingently linking movement‐related patterns of brain activity and visuo‐proprioceptive feedback of the movement supports associative learning (Ramos‐Murguialday et al., 2012; Sirigu et al., 1995).

Changes in sensorimotor brain oscillations involved in planning and execution of movements were used as control signals for the BMI in the aforementioned studies. The sensorimotor rhythm (SMR) is an oscillation within the alpha frequency range of the EEG during a motionless resting state over the central‐parietal brain regions. Movement planning, imagination and execution lead to its suppression. In the present work, we investigate EEG brain oscillations of the alpha frequency, ranging from 8 to 12 Hz, over the motor cortex, and we term them “alpha oscillations.”

Biomarkers could be defined as indicators “of disease state that can be used as a measure of underlying molecular/cellular processes that may be difficult to measure directly in humans” (Boyd et al., 2017). When dealing with a condition as heterogeneous as stroke validated biomarkers of recovery could help plan treatments and support efficient allocation of resource while maximizing outcome for the patients. Alpha brain oscillations have been evaluated as markers of ischaemia and predictors of clinical outcome in acute patients (Finnigan & van Putten, 2013; Rabiller, He, Nishijima, Wong, & Liu, 2015). Desynchronization in the alpha frequency range has also been investigated as a marker of stroke and a predictor of recovery in the same patient group. Tangwiriyasakul, Verhagen, Rutten, and Putten (2014) showed that the recovery of motor function was accompanied by an increase of alpha desynchronization on the ipsilesional side. In subacute patients presenting mild to moderate motor deficits recovery lead to a similar increase of alpha desynchronization on the affected hemisphere (Platz, Kim, Engel, Kieselbach, & Mauritz, 2002). Furthermore, first attempts investigated correlations of alpha desynchronization with motor improvements in chronically impaired patients (Kaiser et al., 2012). In a controlled study, a group of subacute patients with severe deficits used motor imagery, guided by a brain–computer interface, in addition to their regular physiotherapeutic rehabilitation protocol. They showed a higher probability for motor improvements with increased alpha desynchronization (Pichiorri et al., 2015).

In the present work, we investigated what changes in the oscillatory activity of the brain a proprioceptive BMI coupled with physiotherapy produces over the course of a training intervention and if these correlate with recovery in severely paralyzed chronic stroke patients. We hypothesized that functional motor improvements are accompanied by an ipsilesional increase and a contralesional decrease in alpha desynchronization indicating reorganization of compensatory brain activity from the contralesional to the ipsilesional hemisphere. We intend to establish alpha oscillatory activity as a biomarker of motor impairment and as a building block of statistical models of stroke neurorehabilitation.[…]

 

Continue —->  Brain oscillatory activity as a biomarker of motor recovery in chronic stroke – Ray – – Human Brain Mapping – Wiley Online Library

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Figure 1
Schematics of the data acquisition phase and the offline analysis for EEG and EMG. Neurophysiological data was acquired using a 16 channel EEG cap and 4 bipolar EMG electrodes on each arm. EEG data were cleaned from eye movement artifacts and trials containing other artifacts (e.g., cranial EMG, head movements, and so on). EMG data were analyzed to detect compensatory muscle contractions on the healthy upper limb and on the paretic side during resting intervals to identify these trials as contaminated because the muscle activity is a sign of undesired EEG activity. Only data free of artifacts were used for the final analysis of EEG oscillatory activity

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[Fact Sheet] Post-Stroke Rehabilitation Fact Sheet – National Institute of Neurological Disorders and Stroke

Post-Stroke Rehabilitation Fact Sheet

In the United States more than 700,000 people suffer a stroke each year, and approximately two-thirds of these individuals survive and require rehabilitation. The goals of rehabilitation are to help survivors become as independent as possible and to attain the best possible quality of life. Even though rehabilitation does not “cure” the effects of stroke in that it does not reverse brain damage, rehabilitation can substantially help people achieve the best possible long-term outcome.

What is post-stroke rehabilitation?

Rehabilitation helps stroke survivors relearn skills that are lost when part of the brain is damaged. For example, these skills can include coordinating leg movements in order to walk or carrying out the steps involved in any complex activity. Rehabilitation also teaches survivors new ways of performing tasks to circumvent or compensate for any residual disabilities. Individuals may need to learn how to bathe and dress using only one hand, or how to communicate effectively when their ability to use language has been compromised. There is a strong consensus among rehabilitation experts that the most important element in any rehabilitation program is carefully directed,well-focused, repetitive practice—the same kind of practice used by all people when they learn a new skill, such as playing the piano or pitching a baseball.

Rehabilitative therapy begins in the acute-care hospital after the person’s overall condition has been stabilized, often within 24 to 48 hours after the stroke. The first steps involve promoting independent movement because many individuals are paralyzed or seriously weakened. Patients are prompted to change positions frequently while lying in bed and to engage in passive or active range of motion exercises to strengthen their stroke-impaired limbs. (“Passive” range-of-motion exercises are those in which the therapist actively helps the patient move a limb repeatedly, whereas “active” exercises are performed by the patient with no physical assistance from the therapist.) Depending on many factors—including the extent of the initial injury—patients may progress from sitting up and being moved between the bed and a chair to standing, bearing their own weight, and walking, with or without assistance. Rehabilitation nurses and therapists help patients who are able to perform progressively more complex and demanding tasks, such as bathing, dressing, and using a toilet, and they encourage patients to begin using their stroke-impaired limbs while engaging in those tasks. Beginning to reacquire the ability to carry out these basic activities of daily living represents the first stage in a stroke survivor’s return to independence.

For some stroke survivors, rehabilitation will be an ongoing process to maintain and refine skills and could involve working with specialists for months or years after the stroke.

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What disabilities can result from a stroke?

The types and degrees of disability that follow a stroke depend upon which area of the brain is damaged. Generally, stroke can cause five types of disabilities: paralysis or problems controlling movement; sensory disturbances including pain; problems using or understanding language; problems with thinking and memory; and emotional disturbances.

Paralysis or problems controlling movement (motor control)

Paralysis is one of the most common disabilities resulting from stroke. The paralysis is usually on the side of the body opposite the side of the brain damaged by stroke, and may affect the face, an arm, a leg, or the entire side of the body. This one-sided paralysis is called hemiplegia (one-sided weakness is called hemiparesis). Stroke patients with hemiparesis or hemiplegia may have difficulty with everyday activities such as walking or grasping objects. Some stroke patients have problems with swallowing, called dysphagia, due to damage to the part of the brain that controls the muscles for swallowing. Damage to a lower part of the brain, the cerebellum, can affect the body’s ability to coordinate movement, a disability called ataxia, leading to problems with body posture, walking, and balance.

Sensory disturbances including pain

Stroke patients may lose the ability to feel touch, pain, temperature, or position. Sensory deficits also may hinder the ability to recognize objects that patients are holding and can even be severe enough to cause loss of recognition of one’s own limb. Some stroke patients experience pain, numbness or odd sensations of tingling or prickling in paralyzed or weakened limbs, a symptom known as paresthesias.

The loss of urinary continence is fairly common immediately after a stroke and often results from a combination of sensory and motor deficits. Stroke survivors may lose the ability to sense the need to urinate or the ability to control bladder muscles. Some may lack enough mobility to reach a toilet in time. Loss of bowel control or constipation also may occur. Permanent incontinence after a stroke is uncommon, but even a temporary loss of bowel or bladder control can be emotionally difficult for stroke survivors.

Stroke survivors frequently have a variety of chronic pain syndromes resulting from stroke-induced damage to the nervous system (neuropathic pain). In some stroke patients, pathways for sensation in the brain are damaged, causing the transmission of false signals that result in the sensation of pain in a limb or side of the body that has the sensory deficit. The most common of these pain syndromes is called “thalamic pain syndrome” (caused by a stroke to the thalamus, which processes sensory information from the body to the brain), which can be difficult to treat even with medications. Finally, some pain that occurs after stroke is not due to nervous system damage, but rather to mechanical problems caused by the weakness from the stroke.  Patients who have a seriously weakened or paralyzed arm commonly experience moderate to severe pain that radiates outward from the shoulder. Most often, the pain results from lack of movement in a joint that has been immobilized for a prolonged period of time (such as having your arm or shoulder in a cast for weeks) and the tendons and ligaments around the joint become fixed in one position. This is commonly called a “frozen” joint; “passive” movement (the joint is gently moved or flexed by a therapist or caregiver rather than by the individual) at the joint in a paralyzed limb is essential to prevent painful “freezing” and to allow easy movement if and when voluntary motor strength returns.

Problems using or understanding language (aphasia)

At least one-fourth of all stroke survivors experience language impairments, involving the ability to speak, write, and understand spoken and written language. A stroke-induced injury to any of the brain’s language-control centers can severely impair verbal communication. The dominant centers for language are in the left side of the brain for right-handed individuals and many left-handers as well. Damage to a language center located on the dominant side of the brain, known as Broca’s area, causes expressive aphasia. People with this type of aphasia have difficulty conveying their thoughts through words or writing. They lose the ability to speak the words they are thinking and to put words together in coherent, grammatically correct sentences. In contrast, damage to a language center located in a rear portion of the brain, called Wernicke’s area, results in receptive aphasia. People with this condition have difficulty understanding spoken or written language and often have incoherent speech. Although they can form grammatically correct sentences, their utterances are often devoid of meaning. The most severe form of aphasia, global aphasia, is caused by extensive damage to several areas of the brain involved in language function. People with global aphasia lose nearly all their linguistic abilities; they cannot understand language or use it to convey thought.

Problems with thinking and memory

Stroke can cause damage to parts of the brain responsible for memory, learning, and awareness. Stroke survivors may have dramatically shortened attention spans or may experience deficits in short-term memory. Individuals also may lose their ability to make plans, comprehend meaning, learn new tasks, or engage in other complex mental activities. Two fairly common deficits resulting from stroke are anosognosia, an inability to acknowledge the reality of the physical impairments resulting from stroke, and neglect, the loss of the ability to respond to objects or sensory stimuli located on the stroke-impaired side. Stroke survivors who develop apraxia (loss of ability to carry out a learned purposeful movement) cannot plan the steps involved in a complex task and act on them in the proper sequence. Stroke survivors with apraxia also may have problems following a set of instructions. Apraxia appears to be caused by a disruption of the subtle connections that exist between thought and action.

Emotional disturbances

Many people who survive a stroke feel fear, anxiety, frustration, anger, sadness, and a sense of grief for their physical and mental losses. These feelings are a natural response to the psychological trauma of stroke. Some emotional disturbances and personality changes are caused by the physical effects of brain damage. Clinical depression, which is a sense of hopelessness that disrupts an individual’s ability to function, appears to be the emotional disorder most commonly experienced by stroke survivors. Signs of clinical depression include sleep disturbances, a radical change in eating patterns that may lead to sudden weight loss or gain, lethargy, social withdrawal, irritability, fatigue, self-loathing, and suicidal thoughts. Post-stroke depression can be treated with antidepressant medications and psychological counseling.

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What medical professionals specialize in post-stroke rehabilitation?

Post-stroke rehabilitation involves physicians; rehabilitation nurses; physical, occupational, recreational, speech-language, and vocational therapists; and mental health professionals.

Physicians

Physicians have the primary responsibility for managing and coordinating the long-term care of stroke survivors, including recommending which rehabilitation programs will best address individual needs. Physicians also are responsible for caring for the stroke survivor’s general health and providing guidance aimed at preventing a second stroke, such as controlling high blood pressure or diabetes and eliminating risk factors such as cigarette smoking, excessive weight, a high-cholesterol diet, and high alcohol consumption.

Neurologists usually lead acute-care stroke teams and direct patient care during hospitalization. They sometimes participate on the long-term rehabilitation team. Other subspecialists often lead the rehabilitation stage of care, especially physiatrists, who specialize in physical medicine and rehabilitation.

Rehabilitation nurses

Nurses specializing in rehabilitation help survivors relearn how to carry out the basic activities of daily living. They also educate survivors about routine health care, such as how to follow a medication schedule, how to care for the skin, how to move out of a bed and into a wheelchair, and special needs for people with diabetes. Rehabilitation nurses also work with survivors to reduce risk factors that may lead to a second stroke, and provide training for caregivers.

Nurses are closely involved in helping stroke survivors manage personal care issues, such as bathing and controlling incontinence. Most stroke survivors regain their ability to maintain continence, often with the help of strategies learned during rehabilitation. These strategies include strengthening pelvic muscles through special exercises and following a timed voiding schedule. If problems with incontinence continue, nurses can help caregivers learn to insert and manage catheters and to take special hygienic measures to prevent other incontinence-related health problems from developing.

Physical therapists

Physical therapists specialize in treating disabilities related to motor and sensory impairments. They are trained in all aspects of anatomy and physiology related to normal function, with an emphasis on movement. They assess the stroke survivor’s strength, endurance, range of motion, gait abnormalities, and sensory deficits to design individualized rehabilitation programs aimed at regaining control over motor functions.

Physical therapists help survivors regain the use of stroke-impaired limbs, teach compensatory strategies to reduce the effect of remaining deficits, and establish ongoing exercise programs to help people retain their newly learned skills. Disabled people tend to avoid using impaired limbs, a behavior called learned non-use. However, the repetitive use of impaired limbs encourages brain plasticity and helps reduce disabilities.

Strategies used by physical therapists to encourage the use of impaired limbs include selective sensory stimulation such as tapping or stroking, active and passive range-of-motion exercises, and temporary restraint of healthy limbs while practicing motor tasks.

In general, physical therapy emphasizes practicing isolated movements, repeatedly changing from one kind of movement to another, and rehearsing complex movements that require a great deal of coordination and balance, such as walking up or down stairs or moving safely between obstacles. People too weak to bear their own weight can still practice repetitive movements during hydrotherapy (in which water provides sensory stimulation as well as weight support) or while being partially supported by a harness. A recent trend in physical therapy emphasizes the effectiveness of engaging in goal-directed activities, such as playing games, to promote coordination. Physical therapists frequently employ selective sensory stimulation to encourage use of impaired limbs and to help survivors with neglect regain awareness of stimuli on the neglected side of the body.

Occupational and recreational therapists

Like physical therapists, occupational therapists are concerned with improving motor and sensory abilities, and ensuring patient safety in the post-stroke period. They help survivors relearn skills needed for performing self-directed activities (also called occupations) such as personal grooming, preparing meals, and housecleaning. Therapists can teach some survivors how to adapt to driving and provide on-road training. They often teach people to divide a complex activity into its component parts, practice each part, and then perform the whole sequence of actions. This strategy can improve coordination and may help people with apraxia relearn how to carry out planned actions.

Occupational therapists also teach people how to develop compensatory strategies and change elements of their environment that limit activities of daily living. For example, people with the use of only one hand can substitute hook and loop fasteners (such as Velcro) for buttons on clothing. Occupational therapists also help people make changes in their homes to increase safety, remove barriers, and facilitate physical functioning, such as installing grab bars in bathrooms.

Recreational therapists help people with a variety of disabilities to develop and use their leisure time to enhance their health, independence, and quality of life.

Speech-language pathologists

Speech-language pathologists help stroke survivors with aphasia relearn how to use language or develop alternative means of communication. They also help people improve their ability to swallow, and they work with patients to develop problem-solving and social skills needed to cope with the after-effects of a stroke.

Many specialized therapeutic techniques have been developed to assist people with aphasia. Some forms of short-term therapy can improve comprehension rapidly. Intensive exercises such as repeating the therapist’s words, practicing following directions, and doing reading or writing exercises form the cornerstone of language rehabilitation. Conversational coaching and rehearsal, as well as the development of prompts or cues to help people remember specific words, are sometimes beneficial. Speech-language pathologists also help stroke survivors develop strategies for circumventing language disabilities. These strategies can include the use of symbol boards or sign language. Recent advances in computer technology have spurred the development of new types of equipment to enhance communication.

Speech-language pathologists use special types of imaging techniques to study swallowing patterns of stroke survivors and identify the exact source of their impairment. Difficulties with swallowing have many possible causes, including a delayed swallowing reflex, an inability to manipulate food with the tongue, or an inability to detect food remaining lodged in the cheeks after swallowing. When the cause has been pinpointed, speech-language pathologists work with the individual to devise strategies to overcome or minimize the deficit. Sometimes, simply changing body position and improving posture during eating can bring about improvement. The texture of foods can be modified to make swallowing easier; for example, thin liquids, which often cause choking, can be thickened. Changing eating habits by taking small bites and chewing slowly can also help alleviate dysphagia.

Vocational therapists

Approximately one-fourth of all strokes occur in people between the ages of 45 and 65. For most people in this age group, returning to work is a major concern. Vocational therapists perform many of the same functions that ordinary career counselors do. They can help people with residual disabilities identify vocational strengths and develop résumés that highlight those strengths. They also can help identify potential employers, assist in specific job searches, and provide referrals to stroke vocational rehabilitation agencies.

Most important, vocational therapists educate disabled individuals about their rights and protections as defined by the Americans with Disabilities Act of 1990. This law requires employers to make “reasonable accommodations” for disabled employees. Vocational therapists frequently act as mediators between employers and employees to negotiate the provision of reasonable accommodations in the workplace.

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When can a stroke patient begin rehabilitation?

Rehabilitation should begin as soon as a stroke patient is stable, sometimes within 24 to 48 hours after a stroke. This first stage of rehabilitation can occur within an acute-care hospital; however, it is very dependent on the unique circumstances of the individual patient.

Recently, in the largest stroke rehabilitation study in the United States, researchers compared two common techniques to help stroke patients improve their walking.  Both methods—training on a body-weight supported treadmill or working on strength and balance exercises at home with a physical therapist—resulted in equal improvements in the individual’s ability to walk by the end of one year. Researchers found that functional improvements could be seen as late as one year after the stroke, which goes against the conventional wisdom that most recovery is complete by 6 months. The trial showed that 52 percent of the participants made significant improvements in walking, everyday function and quality of life, regardless of how severe their impairment was, or whether they started the training at 2 or 6 months after the stroke.

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Where can a stroke patient get rehabilitation?

At the time of discharge from the hospital, the stroke patient and family coordinate with hospital social workers to locate a suitable living arrangement. Many stroke survivors return home, but some move into some type of medical facility.

Inpatient rehabilitation units

Inpatient facilities may be freestanding or part of larger hospital complexes. Patients stay in the facility, usually for 2 to 3 weeks, and engage in a coordinated, intensive program of rehabilitation. Such programs often involve at least 3 hours of active therapy a day, 5 or 6 days a week. Inpatient facilities offer a comprehensive range of medical services, including full-time physician supervision and access to the full range of therapists specializing in post-stroke rehabilitation.

Outpatient units

Outpatient facilities are often part of a larger hospital complex and provide access to physicians and the full range of therapists specializing in stroke rehabilitation. Patients typically spend several hours, often 3 days each week, at the facility taking part in coordinated therapy sessions and return home at night. Comprehensive outpatient facilities frequently offer treatment programs as intense as those of inpatient facilities, but they also can offer less demanding regimens, depending on the patient’s physical capacity.

Nursing facilities

Rehabilitative services available at nursing facilities are more variable than are those at inpatient and outpatient units. Skilled nursing facilities usually place a greater emphasis on rehabilitation, whereas traditional nursing homes emphasize residential care. In addition, fewer hours of therapy are offered compared to outpatient and inpatient rehabilitation units.

Home-based rehabilitation programs

Home rehabilitation allows for great flexibility so that patients can tailor their program of rehabilitation and follow individual schedules. Stroke survivors may participate in an intensive level of therapy several hours per week or follow a less demanding regimen. These arrangements are often best suited for people who require treatment by only one type of rehabilitation therapist. Patients dependent on Medicare coverage for their rehabilitation must meet Medicare’s “homebound” requirements to qualify for such services; at this time lack of transportation is not a valid reason for home therapy. The major disadvantage of home-based rehabilitation programs is the lack of specialized equipment. However, undergoing treatment at home gives people the advantage of practicing skills and developing compensatory strategies in the context of their own living environment. In the recent stroke rehabilitation trial, intensive balance and strength rehabilitation in the home was equivalent to treadmill training at a rehabilitation facility in improving walking.

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What research is being done?

The National Institute of Neurological Disorders and Stroke (NINDS), a component of the U.S. National Institutes of Health (NIH), has primary responsibility for sponsoring research on disorders of the brain and nervous system, including the acute phase of stroke and the restoration of function after stroke.  The NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development, through its National Center for Medical Rehabilitation Research, funds work on mechanisms of restoration and repair after stroke, as well as development of new approaches to rehabilitation and evaluation of outcomes.  Most of the NIH-funded work on diagnosis and treatment of dysphagia is through the National Institute on Deafness and Other Communication Disorders.  The National Institute of Biomedical Imaging and Bioengineering collaborates with NINDS and NICHD in developing new instrumentation for stroke treatment and rehabilitation.  The National Eye Institute funds work directed at restoration of vision and rehabilitation for individuals with impaired or low vision that may be due to vascular disease or stroke.

The NINDS supports research on ways to enhance repair and regeneration of the central nervous system. Scientists funded by the NINDS are studying how the brain responds to experience or adapts to injury by reorganizing its functions (plasticity)—using noninvasive imaging technologies to map patterns of biological activity inside the brain. Other NINDS-sponsored scientists are looking at brain reorganization after stroke and determining whether specific rehabilitative techniques, such as constraint-induced movement therapy and transcranial magnetic stimulation, can stimulate brain plasticity, thereby improving motor function and decreasing disability. Other scientists are experimenting with implantation of neural stem cells, to see if these cells may be able to replace the cells that died as a result of a stroke.

*An ischemic stroke or “brain attack” occurs when brain cells die because of inadequate blood flow. When blood flow is interrupted, brain cells are robbed of vital supplies of oxygen and nutrients. About 80 percent of strokes are caused by the blockage of an artery in the neck or brain. A hemorrhagic stroke is caused by a burst blood vessel in the brain that causes bleeding into or around the brain.

**Functions compromised when a specific region of the brain is damaged by stroke can sometimes be taken over by other parts of the brain. This ability to adapt and change is known as neuroplasticity.

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Where can I get more information?

For more information on neurological disorders or research programs funded by the National Institute of Neurological Disorders and Stroke, contact the Institute’s Brain Resources and Information Network (BRAIN) at:

BRAIN
P.O. Box 5801
Bethesda, MD 20824
800-352-9424
http://www.ninds.nih.gov

Information also is available from the following organizations:

American Stroke Association: A Division of American Heart Association
7272 Greenville Avenue

Dallas, TX 75231-4596

Tel: 888-4STROKE (478-7653)
Brain Aneurysm Foundation
269 Hanover Street, Building 3

Hanover, MA 02339

Tel: 781-826-5556; 888-BRAIN02 (272-4602)
Brain Attack Coalition
31 Center Drive
Room 8A07

Bethesda, MD 20892-2540

Tel: 301-496-5751
Children’s Hemiplegia and Stroke Assocn. (CHASA)
4101 West Green Oaks Blvd., Ste. 305
PMB 149

Arlington, TX 76016

Tel: 817-492-4325
Fibromuscular Dysplasia Society of America (FMDSA)
20325 Center Ridge Road Suite 620

Rocky River, OH 44116

Tel: 216-834-2410; 888-709-7089
Hazel K. Goddess Fund for Stroke Research in Women
785 Park Road, #3E

New York, NY 10021

Heart Rhythm Society
1325 G Street, N.W.
Suite 400

Washington, DC 20005

Tel: 202-464-3454
Joe Niekro Foundation
PO Box 2876

Scottsdale, AZ 85252

Tel: 602-318-1013
National Aphasia Association
P.O. Box 87

Scarsdale, NY 10583

Tel: 212-267-2814; 800-922-4NAA (4622)
National Stroke Association
9707 East Easter Lane
Suite B

Centennial, CO 80112-3747

Tel: 303-649-9299; 800-STROKES (787-6537)
YoungStroke, Inc.
P.O. Box 692

Conway, SC 29528

Tel: 843-248-9019; 843-655-2835

“Post-Stroke Fact Sheet”, NINDS, Publication date September 2014.

NIH Publication No. 14-1846

Stroke fact sheet available in multiple languages through MedlinePlus

Back to Stroke Information

See a list of all NINDS disorders


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Prepared by:
Office of Communications and Public Liaison
National Institute of Neurological Disorders and Stroke
National Institutes of Health
Bethesda, MD 20892
NINDS health-related material is provided for information purposes only and does not necessarily represent endorsement by or an official position of the National Institute of Neurological Disorders and Stroke or any other Federal agency. Advice on the treatment or care of an individual patient should be obtained through consultation with a physician who has examined that patient or is familiar with that patient’s medical history.

All NINDS-prepared information is in the public domain and may be freely copied. Credit to the NINDS or the NIH is appreciated.

 

via Post-Stroke Rehabilitation Fact Sheet | National Institute of Neurological Disorders and Stroke

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[ARTICLE] Recovery of upper limb function is greatest early after stroke but does continue to improve during the chronic phase: a two-year, observational study – Full Text

Abstract

Objectives

Investigate upper limb (UL) capacity and performance from <14-days to 24-months post-stroke.

Design

Longitudinal study of participants with acute stroke, assessed ≤14-days, 6-weeks, 3-, 6-, 12-, 18-, and 24-months post-stroke.

Setting

Two acute stroke units.

Main outcome measures: Examination of UL capacity using Chedoke McMaster Stroke Assessment (combined arm and hand scores, 0 to 14), performance using Motor Activity Log (amount of movement and quality of movement, scored 0 to 5), and grip strength (kg) using Jamar dynamometer. Random effects regression models were performed to explore the change in outcomes at each time point. Routine clinical imaging was used to describe stroke location as cortical, subcortical or mixed.

Results

Thirty-four participants were enrolled: median age 67.7 years (IQR 60.7 to 76.2), NIHSS 11.5 (IQR 8.5 to 16), female n = 10 (36%). The monthly rate of change for all measures was consistently greatest in the 6-weeks post-baseline. On average, significant improvements were observed to 12- months in amount of use (median improvement 1.81, 95% CI 1.35 to 2.27) and strength (median improvement 8.29, 95% CI 5.90 to 10.67); while motor capacity (median improvement 4.70, 95% CI 3.8 to 5.6) and quality of movement (median improvement 1.83, 95% CI 1.37 to 2.3) improved to 18-months post-stroke. Some individuals were still demonstrating gains at 24-months post-stroke within each stroke location group.

Conclusion

This study highlights that the greatest rate of improvement of UL capacity and performance occurs early post-stroke. At the group level, improvements were evident at 12- to 18-months post-stroke, but at the individual level improvements were observed at 24-months.

Introduction

Up to 70% of individuals experience difficulties using their upper limb (UL, arm and hand) to perform meaningful activities after stroke [1]. There is an assumption that when a stroke survivor demonstrates a change in activity, it is underpinned by an improvement in their capacity (i.e., what a person can do in the clinical environment) and performance (i.e., does a person actually use their UL in real world environments outside of the clinic) [2]. However, UL recovery post-stroke is unlikely to be this simplistic [3]. Understanding how capacity and performance change over years post-stroke might help to identify which patients to target and when during their recovery.

Previous research has noted distinct recovery profiles during inpatient [4][5] and outpatient [6] rehabilitation. Firstly, survivors may demonstrate improvements in both capacity and performance after stroke. Secondly, survivors may demonstrate an improvement in capacity but not performance. Lastly, survivors may demonstrate little or no change in both capacity and performance. An improvement in performance but not capacity has not been documented in the literature. Combined, these profiles support our rationale that UL capacity and performance are interrelated, yet are different constructs that must be measured separately.

Stroke recovery is a long-term goal. It is important to complete observational studies that track recovery to establish whether there is a discrepancy between capacity and performance in the long-term. To date, longitudinal tracking of recovery has largely lacked investigation of natural recovery from an acute time point post-stroke (first 7- to 14-days), long-term follow up of patients beyond 3- to 6-months post-stroke, and characterisation of stroke variables such as lesion type and location that may modify or interact with observed recovery profiles [7].

In this exploratory study our objectives were to determine 1) whether UL capacity and performance improve over the first 24-months after stroke; and 2) if there is a window of greatest improvement in UL capacity and performance. This information is important to develop an understanding of the longterm timecourse of recovery after stroke to support evidence-based clinical practice guidelines to inform upper limb rehabilitation services.

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Continue —-> Recovery of upper limb function is greatest early after stroke but does continue to improve during the chronic phase: a two-year, observational study – ScienceDirect

Fig. 2

Fig. 2. Upper limb motor capacity (Chedoke), performance (quality of movement & amount of use), and grip strength over 24-months post-stroke (n = 28)

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[Abstract] Relationship Between Clinical Measures of Upper Limb Movement Quality and Activity Poststroke

Background. Understanding the relationship between movement quality (impairment) and performance (activity) in poststroke patients is important for rehabilitation intervention studies. This has led to an interest in kinematic characterization of upper limb motor impairment. Since instrumented motion analysis is not readily clinically available, observational kinematics may be a viable alternative.

Objective. To determine if upper limb movement quality during a reach-to-grasp task identified by observation could be used to describe the relationship between motor impairments and the time to perform functional tasks.

Methods. Cross-sectional, secondary analysis of baseline data from 141 participants with stroke, age 18 to 85 years, who participated in a multicenter randomized controlled trial. Clinical assessment of movement quality using the Reaching Performance Scale for Stroke (RPSS–Close and Far targets) and of performance (activity) from the Wolf Motor Function Test (WMFT–7 items) was assessed. The degree to which RPSS component scores explained scores on WMFT items was determined by multivariable regression.

Results. Clinically significant decreases (>2 seconds) in performance time for some of the more complex WMFT tasks involving prehension were predicted from RPSS–Close and Far target components. Trunk compensatory movements did not predict either increases or decreases in performance time for the WMFT tasks evaluated. Overall, the strength of the regression models was low.

Conclusions. In lieu of kinematic analysis, observational clinical movement analysis may be a valid and accessible method to determine relationships between motor impairment, compensations and upper limb function in poststroke patients. Specific relationships are unlikely to generalize to all tasks due to kinematic redundancy and task specificity.

 

via Relationship Between Clinical Measures of Upper Limb Movement Quality and Activity Poststroke – Mindy F. Levin, Vimonwan Hiengkaew, Yongchai Nilanont, Donna Cheung, David Dai, Jennifer Shaw, Mark Bayley, Gustavo Saposnik, 2019

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[Abstract] Improvement of Upper Limb Motor Control and Function After Competitive and Noncompetitive Volleyball Exercises in Chronic Stroke Survivors: A Randomized Clinical Trial.

Abstract

OBJECTIVES:

To investigate the effects of competitive and noncompetitive volleyball exercises on the functional performance and motor control of the upper limbs in chronic stroke survivors.

DESIGN:

Randomized clinical trial.

SETTING:

Outpatient rehabilitation center.

PARTICIPANTS:

Chronic stroke survivors (N=48).

INTERVENTIONS:

Participants were randomly assigned to competitive (n=16) or noncompetitive (n=16) volleyball exercise groups (60min/d volleyball exercise+30min/d traditional rehabilitation, 3d/wk for 7wk) and control group (n=16).

MAIN OUTCOME MEASURES:

Reach and grasp motor control measures were evaluated through kinematic analysis. Functional outcomes were assessed via Motor Activity Log, Wolf Motor Function Test (WMFT), Box and Block Test, and Wrist Position Sense Test.

RESULTS:

Significant improvement of functional performance was observed in both competitive (P<.0001) and noncompetitive volleyball exercise groups (P<.01), but not in the control group (P>.05), with the exception of WMFT score. Volleyball training, in general, resulted in more efficient spatiotemporal control of reach and grasp functions, as well as less dependence on feedback control as compared to the control group. Moreover, the competitive volleyball exercise group exhibited greater improvement in both functional performance and motor control levels.

CONCLUSIONS:

Volleyball team exercises, especially in a competitive format, resulted in enhancing the efficacy of the preprogramming and execution of reach and grasp movements, as well as a shift from feedback to feedforward control of the affected upper limb in chronic stroke survivors. This may well be a potential underlying mechanism for improving functional performance.

via:
https://www.ncbi.nlm.nih.gov/pubmed/30419232

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[WEB SITE] Biorobotics Laboratories

At the Swiss Federal Institute of Technology in Lausanne, professor Auke Ijspeert and its team use robots as a scientific tool to better understand mobility in living beings and explore the secret of the spinal cord

Brushing teeth, making coffee, unlocking a door – our brain is the central processing unit for many physical movements. This might make you think that without the brain, nothing would happen at all. But that’s not quite true. When a doctor uses a small hammer to tap our knee, we experience a reflexive kick of the lower leg. And when we accidentally touch a hot stovetop, our hand will jerk back immediately. It’s not the brain that’s responsible for such movements, but another part of the central nervous system: the spinal cord. A headless chicken is, albeit somewhat morbid, proof of the fact that a living creature is able to move without a brain. The chicken flaps and runs about for several seconds even after its head has been severed from the body.

But how do these motor circuits in the spine work? What are the underlying control mechanisms for the movement of vertebrates? This is just one of the questions investigated by Auke Ijspeert’s team of 17 at the EPFL in Lausanne. The scientists chose a somewhat unusual approach for their research – they’re building robots. That also explains the name of their work place: Biorobotics Laboratory, or Biorob for short. “We use robots as a scientific tool to help us better understand mobility in living beings,” explains Auke Ijspeert. It’s not so much about building a robot that looks spectacular or is able to work autonomously: “With our robots, we want to contribute to research in the neurosciences and biomechanics.”

Evolutionary biology also benefits from the team’s work. “In many animals, motor control happens mostly in the spinal cord. I find that fascinating.”

The Pleurobot by Auke Ijspeert and his team attracted particular attention. What at first glance looks like a paleontological skeleton assembly kit is actually a sophisticated reproduction of a salamander’s musculoskeletal system. Watching the Pleurobot, which is powered by 27 motors, move in water or on land leaves the observer in awe. The similarity to a salamander’s natural movement is remarkable. The Biorob team made every effort to design the Pleurobot to be as similar to a salamander as possible: They used 3D X-ray videos to analyze every limb of a salamander in motion. This was followed by meticulous mechanical and motor function calculations.

THE BRAIN DOES NOT HAVE SOLE CONTROL

It’s no coincidence that biomechanical research focuses on amphibians. Their locomotor system is interesting because it permits studying the gradual transition of movement on land and in water. Several years ago, neurobiologists were able to show that salamanders can be “remote controlled” by stimulating their spinal cord. Weak electrical stimulation lets the salamander walk; increasing the stimulus beyond a certain threshold results in the salamander performing its typical swimming movements. This ultimately means that the salamander’s brain is not fully in control of the locomotor system. In fact, the spinal cord and limbs form an almost autonomous control and locomotor system. “The brain merely has a stimulating function,” says Auke Ijspeert. The Pleurobot follows this functional principle: Transitioning from walking to swimming movements requires only an increase in the electrical current. “When we control the Pleurobot remotely, we don’t need to control each individual motor. Similar to the brain of a salamander, we only determine the direction, the speed, and the intensity of the stimulus.” The function of the spinal cord in the Pleurobot is assumed by a microcontroller which – put simply – has been programmed with mathematical models of a salamander’s spinal neural network.

THE USE OF ROBOTS TO UNDERSTAND THE NERVOUS SYSTEM

But why go to all this effort? “Our interest is to fundamentally understand how the nervous system in a spinal column functions,” explains Auke Ijspeert. It’s a very complex subject that has by no means been exhaustively researched. The spinal cord’s well-protected location in the canal of the vertebral column in particular makes it very difficult to measure its neuronal activity – even more so than the activity of the brain itself. “You can’t just stick some electrodes into the spinal cord of a moving animal and measure what’s happening.” One reason why Auke Ijspeert likes this combination of biology and robotics is that other scientific disciplines benefit from it. A fundamental understanding of movement can help in the manufacture of neuroprosthetics, for example. Discoveries in the fields of neuronal systems and the spinal cord are incorporated into research work on new paraplegia therapies.

With its Envirobot – a snake-like swimming robot – the EPFL team have also developed and built an inspection robot. It can be used to detect and measure water pollution, for example.

But Auke Ijspeert’s team researches much more than amphibian robots. A cat-like robot named Cheetah and humanoid robots are also part of the lab’s inventory. For many of its projects, including the Pleurobot, the Biorobotics Laboratory uses DC motors from maxon. The modular Dynamixel actuators by Robotis are used mainly in robotics projects. These modules mainly incorporate maxon RE-max motors, the tried and tested brushed motors with an ironless winding. Auke Ijspeert compliments the Swiss drive specialist: “We like maxon a lot!”

By Adrian Venetz

 

via Biorobotics Laboratories

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[Abstract] Improvement of upper limb motor control and function after competitive and non-competitive volleyball exercises in chronic stroke survivors: A randomized clinical trial

Abstract

Objectives

To investigate the effects of competitive and non-competitive volleyball exercises on the functional performance and motor control of the upper limbs in chronic stroke survivors.

Design

Randomized clinical trial.

Setting

Outpatient rehabilitation center.

Participants

Forty-eight chronic stroke survivors.

Interventions

Participants were randomly assigned to competitive (n=16) or non-competitive (n=16) volleyball exercise groups (60 min/day volleyball exercise + 30 min/day traditional rehabilitation, 3 day/week for 7 weeks) and control group (n=16).

Main outcome measures

Reach and grasp motor control measures were evaluated through kinematic analysis. Functional outcomes were assessed via Motor Activity Log, Wolf Motor Function Test, Box and Block Test, as well as, Wrist Position Sense Test.

Results

Significant improvement of functional performance was observed in both competitive (P <0.0001) and non-competitive volleyball exercise groups (P <0.01), but not in the control group (P >0.05), with the exception of Wolf Motor Function Test score. Volleyball training, in general, resulted in more efficient spatiotemporal control of reach and grasp functions, as well as less dependence on feedback control as compared to the control group. Moreover, the competitive volleyball exercise group exhibited greater improvement in both functional performance and motor control levels.

Conclusions

Volleyball team exercises, especially in a competitive format, resulted in enhancing the efficacy of the pre-programming and execution of reach and grasp movements, as well as a shift from feedback to feedforward control of the affected upper limb in chronic stroke survivors. This may well be a potential underlying mechanism for improving functional performance.

 

via Improvement of upper limb motor control and function after competitive and non-competitive volleyball exercises in chronic stroke survivors: A randomized clinical trial – Archives of Physical Medicine and Rehabilitation

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[BLOG POST] Motor Control • What Does it Do – Clinical Education

Motor Control / Muscle Activation / Motor Re-education, whatever you might want to call it — is one of the crucial keys to a successful rehabilitation program especially in sports medicine rehabilitation but is often times overlooked by many clinicians.

What Happens After Injury and How it relates to Motor Control?

Injury causes chemical pain and swelling, both of which have inhibitory effect on muscle’s ability to contract.

“Persistent pain alone will cause muscle weakness due to decrease in neural output” — P. Brukner & K. Khan

Motor ControlTherefore, muscle conditioning or motor control must commence after initial injury along with pain and inflammation management. This process or treatment aims to teach the patient how to activate those muscles that are inhibited following an injury. For example, following a shoulder impingement injury, local stabilizers of the shoulder like the supraspinatus are inflamed and inhibited. Athletes or clients should be taught how to activate and control that damaged muscle before proceeding to other forms of muscle conditioning and/or strengthening.

I have been blessed to grew up in a university and clinics which taughts and applies the practice of activating first the local stabilizers of the body is the first priority rather than taking theshortcut of activating global muscles thinking that if global muscles are activated so do the local stabilizers. But sadly, it is not always the case. I am devastated to see so many clinics trying to fire up global muscles without knowing if local stabilizers are right on point before firing their guns.

“It’s like pulling the trigger of a gun without positioning the gun first to hit it’s target.”

It is important to differentiate what a global muscles and local muscles are. Global muscles are the large, torque-producing muscles, whereas local muscles are responsible for local stability. For example, in the shoulder region, global muscles are your deltoids & upper trapezius, while local muscles are your rotator cuff like supraspinatus and infraspinatus. In the recent years of study, there has been an increasing understanding of the important role of activating first the local stabilizers of the joint before the torque producing global muscles.

When There is No Motor Control..

When there is no motor control, there is a incorrect motor patterning syndrome, especially after injury.

Clinical Sports Medicine BookAccording to the book, Brukner & Khan’s Clinical Sports Medicine (Mcgraw Medical)..“Rehabilitation of these incorrect motor patterning syndrome relies on careful assessment of the pattern of movement, theindividual strength, function of the involved muscles and the flexibility of the muscles and joints. As this abnormal movement pattern has been developed over a lengthy period, it is necessary for the patient to learn a new movement pattern. This takes time and patience.The movement should be broken down into components and the patient must initially learn to execute each component individually.Eventually, the complete correct movement pattern will be learned.”

Tips

How To Do Motor Control? Tips and Tricks.

As I practice in clinics, I always use cuing and tactile / verbal feedback to facilitate control of desired movements. For me to feel if the right muscle is being activated I always palpate 2 groups of muscles. One is the muscle in which I want to control or facilitateand another are the groups of muscles which I do not want to be substituting during motor learning. I find this effective in facilitating motor control. Other techniques I use are visualization of the correct muscle action. Also, I often times demonstrate and describe the muscle action to the patient. One technique which I haven’t used yet because it is so time consuming, but I think will be more effective is to have anatomical illustrations of the muscles involved around what you want to monopolize. Use of instructions that cue the correct action also helps. For example, phrases like “pull your navel towards towards your spine” to facilitate control of transversus abdominis. One of the best advise that I would give is to focus on precision. The patient has to concentrate and focus on the precise muscle action to be achieved. It should be stressed that activation of the muscles should be a gentle action. Other muscles should remain relaxed during this localize exercise.

Once again..

“Do not pull the trigger of gun without positioning the gun first to hit it’s target.”

Reference:

  • Clinical Sports Medicine Revised 3rd Edition by Peter Brukner and Karim Khan

I like to hear it from you. What are your thoughts on these? Do you agree or disagree?

via Clinical Education • Motor Control – What Does it Do

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[Abstract] A meta-analysis of the efficacy of anodal transcranial direct current stimulation for upper limb motor recovery in stroke survivors

Abstract

Study Design

Systematic review and meta-analysis.

Introduction

Prior reviews on the effects of anodal transcranial direct current stimulation (a-tDCS) have shown the effectiveness of a-tDCS on corticomotor excitability and motor function in healthy individuals but nonsignificant effect in subjects with stroke.

Purpose

To summarize and evaluate the evidence for the efficacy of a-tDCS in the treatment of upper limb motor impairment after stroke.

Methods

A meta-analysis of randomized controlled trials that compared a-tDCS with placebo and change from baseline.

Results

A pooled analysis showed a significant increase in scores in favor of a-tDCS (standard mean difference [SMD]=0.40, 95% confidence interval [CI]=0.10–0.70, p=0.010, compared with baseline). A similar effect was observed between a-tDCS and sham (SMD=0.49, 95% CI=0.18–0.81, p=0.005).

Conclusion

This meta-analysis of eight randomized placebo-controlled trials provides further evidence that a-tDCS may benefit motor function of the paretic upper limb in patients suffering from chronic stroke.

via A meta-analysis of the efficacy of anodal transcranial direct current stimulation for upper limb motor recovery in stroke survivors – Journal of Hand Therapy

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[ARTICLE] Upper Limb Motor Impairment Post Stroke – Full Text

Synopsis

Understanding upper limb impairment after stroke is essential to planning therapeutic efforts to restore function. However determining which upper limb impairment to treat and how is complex for two reasons: 1) the impairments are not static, i.e. as motor recovery proceeds, the type and nature of the impairments may change; therefore the treatment needs to evolve to target the impairment contributing to dysfunction at a given point in time. 2) multiple impairments may be present simultaneously, i.e., a patient may present with weakness of the arm and hand immediately after a stroke, which may not have resolved when spasticity sets in a few weeks or months later; hence there may be a layering of impairments over time making it difficult to decide what to treat first. The most useful way to understand how impairments contribute to upper limb dysfunction may be to examine them from the perspective of their functional consequences. There are three main functional consequences of impairments on upper limb function are: (1) learned nonuse, (2) learned bad-use, and (3) forgetting as determined by behavioral analysis of tasks. The impairments that contribute to each of these functional limitations are described.

The nature of upper limb motor impairment

According to the International Classification of Functioning, Disability and Health model (ICF) (Geyh, Cieza et al. 2004), impairments may be described as (1) impairments of body function such as a significant deviation or loss in neuromusculoskeletal and movement related function related to joint mobility, muscle power, muscle tone and/or involuntary movements, or (2) impairment of body structures such as a significant deviation in structure of the nervous system or structures related to movement, for example the arm and/or hand. A stroke may lead to both types of impairments. Upper limb impairments after stroke are the cause of functional limitations with regard to use of the affected upper limb after stroke, so a clear understanding of the underlying impairments is necessary to provide appropriate treatment. However understanding upper limb impairments in any given patient is complex for two reasons: 1) the impairments are not static, i.e. as motor recovery proceeds, the type and nature of the impairments may change; therefore the treatment needs to evolve to target the impairment contributing to dysfunction at a given point in time. 2) multiple impairments may be present simultaneously, i.e., a patient may present with weakness of the arm and hand immediately after a stroke, which may not have resolved when spasticity sets in a few weeks or months later; hence there may be a layering of impairments over time making it difficult to decide what to treat first. It is useful to review the progression of motor recovery as described by Twitchell (Twitchell 1951) and Brunnstrom (Brunnstom 1956) to understand how impairments may be layered over time (Figure 1).

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Sequential progression of motor recovery as described by Twitchell and Brunstrumm. Note that while recovery is proceeding from one stage to the next, residual impairment from preceding stages may still be present leading to the layering of impairment. Also note the underlying physiological processes that may account for progression from one stage to the next.

Understanding motor impairment from a functional perspective

The most useful way to understand how impairments contribute to upper limb dysfunction may be to examine them from the perspective of their functional consequences. There are three main functional consequences of stroke on the upper limb: (1) learned nonuse, (2) learned bad-use, and (3) forgetting as determined by behavioral analysis of a task such as reaching for a food pellet and bringing it to the mouth in animal models of stroke (Whishaw, Alaverdashvili et al. 2008). These are equally valid for human behavior. Each of the functional consequences and the underlying impairments are elaborated below.[…]

 

Continue —>  Upper Limb Motor Impairment Post Stroke

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