New model of how brain functions are organized may revolutionize stroke rehab

A new model of brain lateralization for movement could dramatically improve the future of rehabilitation for stroke patients, according to Penn State researcher Robert Sainburg, who proposed and confirmed the model through novel virtual reality and brain lesion experiments.

Since the 1860s, neuroscientists have known that the human brain is organized into two hemispheres, each of which is responsible for different functions. Known as neural lateralization, this functional division has significant implications for the control of movement and is familiar in the phenomenon of handedness.

Understanding the connections between neural lateralization and motor control is crucial to many applications, including the rehabilitation of stroke patients. While most people intuitively understand handedness, the neural foundations underlying motor asymmetry have until recently remained elusive, according to Sainburg, professor of kinesiology and neurology and participant in the neuroscience and physiology graduate programs at the University’s Huck Institutes of the Life Sciences.

Research by Sainburg and his colleagues in the Center for Motor Control and published in the journal Brain has revealed a new model of motor lateralization that accounts for the neural foundations of handedness. The discovery could fundamentally change the way post-stroke rehabilitation is designed.

"Each hemisphere of the brain is specialized for different aspects of motor control, and thus each arm is ‘dominant’ for different features of movement," said Sainburg. "The dominant arm is used for applying specific force sequences — such as when slicing a loaf of bread with a knife — and the other arm is used for impeding forces to maintain stable posture, such as holding the loaf of bread. Together these specialized control mechanisms are seamlessly integrated into every day activities.

"Our research has shown that this integration breaks down in neural disorders such as stroke, which produces different motor deficits depending on whether the right or left hemisphere has been damaged," Sainburg continued. "Traditionally, physical rehabilitation professionals have used the same protocols to practice movements of the paretic arm, regardless of the hemisphere that has been damaged. Our research shows that each arm should be treated for different control deficits, and it also indicates that therapists should directly retrain patients in how to use the two arms together in order to recover function."

In preparing to test their model, Sainburg and his team selected study participants from the New Mexico Veterans Administration Hospital and Penn State Milton S. Hershey Medical Center based on specific criteria in order to accurately distinguish the motor control mechanisms specific to each brain hemisphere. Participants were then asked to perform a series of tasks on a virtual reality interface, programmed and designed by Sainburg, which allowed the researchers to record detailed 3D position and motion data. The data for all the participants’ hand trajectories and final positions were then aggregated to compare the effects of left versus right hemisphere damage on different aspects of control.

"Our results indicated that while both groups of patients showed similar clinical impairment in the contralesional arm, this was produced by different motor control deficits," Sainburg said. "Right hemisphere damaged patients were able to make straight movements that were directed toward the targets, but were unable to stabilize their arms in the targets at the end of motion. In contrast, left hemisphere damaged patients were unable to make straight and efficient movements, but had no difficulty stabilizing their arms at the end of motion. These results confirmed that each hemisphere contributes unique control to its contralesional arm, verifying why our arms seem different when we use them for the same tasks."

Results mirror those of Sainburg’s prior studies of motor deficits in unilateral stroke patients, focused on the ipsilesional arm, which formed the basis for his model of lateralization.

"Because both arms in stroke patients show motor deficits that are specific to the hemisphere that was damaged, we have concluded that the left arm is not simply controlled with the right hemisphere and vice versa," Sainburg said. "This is a revolutionarily new perspective on sensorimotor control: each hemisphere contributes different control mechanisms to the coordination of both arms, regardless of which arm is considered dominant."

Sainburg and his colleagues are currently designing follow-up studies that will aid the development of new rehabilitation protocols addressing the specific motor deficits associated with each hemisphere.

New Research on the Effects of Traumatic Brain Injury (TBI)

Considerable opportunity exists to improve interventions and outcomes of traumatic brain injury (TBI) in older adults, according to three studies published in the recent online issue of NeuroRehabilitation by researchers from the Icahn School of Medicine at Mount Sinai.

An Exploration of Clinical Dementia Phenotypes Among Individuals With and Without Traumatic Brain Injury

Some evidence suggests that a history of TBI is associated with an increased risk of dementia later in life, but the clinical features of dementia associated with TBI have not been well investigated.  Researchers at the Icahn School of Medicine as well as other institutions analyzed data from elderly individuals with dementia with and without a history of TBI to characterize the clinical profiles of patients with post-TBI dementia.

The results of the study indicate that compared to older adults with dementia with no history of TBI, those with a history of TBI had higher fluency and verbal memory scores and later onset of decline. However, their general health was worse, they were more likely to have received medical attention for depression, and were more likely to have a gait disorder, falls, and motor slowness.  These findings suggest that dementia among individuals with a history of TBI may represent a unique clinical phenotype that is distinct from that seen among elderly individuals who develop dementia without a history of TBI.

"Our study indicates that individuals with dementia and without a history of TBI may present clinical characteristics that differ in subtle but meaningful ways," said Kristen Dams-O’Connor, PhD, first author of the study and an Assistant Professor of Rehabilitation Medicine at the Icahn School of Medicine at Mount Sinai. "It is imperative that clinicians take a history of TBI into account when making dementia diagnoses."

For this study, researchers used data from the National Alzheimer’s Coordinating Center (NACC) Uniform Data Set (UDS) collected between September 2005 and May 2012 to analyze 332 elderly individuals with dementia and a history of TBI and 664 elderly individuals without dementia who do have a history of TBI. Statistical analyses focused on evaluating differences in the areas of neurocognitive functioning, psychiatric functioning, medical history and health, clinical characteristics of dementia, and dementia diagnosis using data collected at the baseline (first) NACC study visit.

Mortality of Elderly Individuals with TBI in the First 5 Years Following Injury

After observing a high rate of mortality among patients over the age of 55 in the first five years after sustaining a TBI, researchers at the Icahn School of Medicine at Mount Sinai were interested in learning more about the precise causes for what may be considered a premature death.

The results of this study indicate that for approximately a third of the patients, death one to five years after TBI resulted from health conditions that were present at the time of injury before the onset of TBI, suggesting a continuation of an already ongoing process. The remainder of patients died from conditions that appeared to unfold in the years after injury. According to the authors, each cause of death in this sample would have required pro-active medical management, medical intervention and medication compliance.

"Like those with other chronic health conditions, individuals with TBI could benefit from the development of a disease management model of primary care," said one of the study authors, Wayne Gordon, PhD, Jack Nash Professor and Vice Chair of the Department of Rehabilitation Medicine at the Icahn School of Medicine at Mount Sinai and Chief of the Rehabilitation Psychology and Neuropsychology service. "This study suggests that close medical management and lifestyle interventions may help to prevent premature death among elderly survivors of TBI in the future."

Researchers reviewed the charts of 30 individuals over the age of 55 who completed inpatient acute rehabilitation during the period from 2003-2009 and who died one to four years after TBI, and then compared that data to a matched sample of 30 patients who did not die. They found that 53 percent of deceased subjects had been diagnosed with gait abnormalities, 32 percent were taking respiratory medications at admission, and 17 percent were taking respiratory medications at discharge. Compared to patients who survived several years after injury, deceased patients were discharged from the hospital with significantly more medications.

Inpatient Rehabilitation for Traumatic Brain Injury: The Influence of Age on Treatments and Outcomes

For this study, researchers analyzed the difference in treatment and outcomes between elderly and younger patients with TBI. They found that patients over 65 had lower brain injury severity and a shorter length of stay in acute care. Elderly patients also received fewer hours of rehabilitation therapy, due to a shorter length of stay, and fewer hours of treatment per day, especially from psychology and therapeutic recreation. They gained less functional ability during and after rehabilitation, and had a very high mortality rate.

"We know significantly more about the treatment received by adolescents and young adults with TBI than we do about those over 65," said Marcel Dijkers, PhD, lead author and Research Professor in the Department of Rehabilitation Medicine at Mount Sinai.  "Our data indicates that elderly people can be rehabilitated successfully, but it raises a number of questions. For instance: is the high mortality due to the TBI or is it the result of the continuation of a condition that began pre-TBI?"

The researchers analyzed data on 1,419 patients with TBI admitted to nine TBI rehabilitation inpatient programs across the country between 2009 and 2011. They collected data through abstracting of medical records, point-of-care forms completed by therapists, and interviews conducted three and nine months after discharge.

Gets stroke patients back on their feet

A robot is now being built to help stroke patients with training, motivation and walking.

In Europe, strokes are the most common cause of physical disability among the elderly. This often result in paralysis of one side of the body, and many patients suffer much reduced physical mobility and are often unable to walk on their own. These are the hard facts the EU project CORBYS has taken seriously. Researchers in six countries are currently developing a robotic system designed to help stroke patients re-train their bodies. The concept is based on helping the patient by constructing a system consisting of powered orthosis to help patient in moving his/her legs and a mobile platform providing patient mobility.

The CORBYS researchers are also working with the cognitive aspects. The aim is to enable the robot to interpret data from the patient and adapt the training programme to his or her capabilities and intention. This will bring rehabilitation robots to the next level.

Back to walking normally
It is vital to get stroke patients up on their feet as soon as possible. They must have frequent training exercises, and re-learn how to walk so that they can function as good as possible on their own.
Why a robot? “Absolutely, because it is difficult to meet these requirements using today’s work-intensive manual method where two therapists assisting the patient by lifting one leg after the other”, says ICT researcher Anders Liverud at SINTEF, which is one of the CORBYS project partners.

Robot-patient learning
CORBYS involves the use of physiological data such as heart rate, temperature and muscle activity measurements to provide feedback to the therapist and help control the robot. Do the patient’s legs always go where the patient want? Is the patient getting tired and stressed?

“The walking robot has several settings, and the therapist selects the correct mode based on how far the patient has come in his or her rehabilitation”, says Liverud. “The first step is to attach sensors to the patient’s body and let them walk on a treadmill. A therapist manually corrects the walking pattern and, with the help of the sensors, create a model of the patient’s walking pattern”, he says.

In the next mode, the system adjusts the walking pattern to the defined model. New adjustments are made and are used to improve optimisation of the walking pattern.

“The patient wears an EEG cap which measures brain activity”, says Liverud. “By using these signals combined with input from other physiological and system sensors, the robotic system registers whether the patient wants to stop, change speed or turn, and can adapt immediately”, he says. “The robot continues to correct any walking pattern errors. However, since it also allows the patient the freedom to decide where and how he or she walks, the patient experiences control and keeps motivation to continue with the training”, says Liverud.

Working with Europe
The European researchers have now completed specification of the system and its components, and construction of the robot is underway.
Construction involves a large team. The University of Bremen is heading the project and developing the architecture to integrate all system modules, and German wheelchair, orthosis and robotics experts are constructing the mechanical components, while two UK universities are working with cognitive aspects. Spanish specialists are addressing brain activity measurements and the University of Brussels is looking into robot control. SINTEF is working with the sensors and the final functional integration of the system. In a year’s time construction will be completed and the robot will be tested on stroke patients at rehabilitation institutes in Slovenia and Germany. The CORBYS project has a total budget of EUR 8.7 million.

Lower Extremity Functional Electrical Stimulation Cycling Promotes Physical & Neurological Recovery In Chronic Spinal Cord Injury

A new study by Kennedy Krieger Institute’s International Center for Spinal Cord Injury (Epub ahead of print) finds that long-term lower extremity functional electrical stimulation (FES) cycling, as part of a rehabilitation regimen, is associated with substantial improvements in individuals with chronic spinal cord injury (SCI). Improvements include neurological and functional gains, as well as enhanced physical health demonstrated by decreased fat, increased muscle mass and improved lipid profile. Prior to this study’s publication in the Journal of Spinal Cord Medicine, the benefits of activity-based restorative therapy (ABRT) programs, such as FES cycling, were largely anecdotal despite publicity in conjunction with the recovery of actor and activist Christopher Reeve.

In FES, small electrical pulses are applied to paralyzed muscles to stimulate movement. In the case of FES cycling, FES pulses prompt the legs of an individual with SCI to “cycle” on an adapted stationary recumbent bicycle. The repetitive activity offers cardiovascular exercise similar to that which an able-bodied individual achieves through walking, but this new research shows that the results go far beyond basic health benefits.

“Exercise has not been commonly advocated for individuals with paralysis because of the assumption that it is of little benefit and it is challenging to exercise limbs that an individual cannot voluntarily move,” said John W. McDonald, M.D., Ph.D., senior study author and director of the International Center for Spinal Cord Injury at the Kennedy Krieger Institute. “However, we found that FES cycling is a practical form of exercise that provides substantial benefits, including improved physical integrity, enhanced neurological and functional performance, increased muscle size and strength, reduced muscle spasticity and improved quality of life.”

Japan’s Robot Suit Gets Global Safety Certificate

A robot suit that can help the elderly or disabled get around was given its global safety certificate in Japan on Wednesday, paving the way for its worldwide rollout.

The Hybrid Assistive Limb, or HAL, is a power-assisted pair of legs developed by Japanese robot maker Cyberdyne, which has also developed similar robot arms.

A quality assurance body issued the certificate based on a draft version of an international safety standard for personal robots that is expected to be approved later this year, the ministry for the economy, trade and industry said.

The metal-and-plastic exoskeleton has become the first nursing-care robot certified under the draft standard, a ministry official said.

Battery-powered HAL, which detects muscle impulses to anticipate and support the user’s body movements, is designed to help the elderly with mobility or help hospital or nursing carers to lift patients.

Cyberdyne, based in Tsukuba, northeast of Tokyo, has so far leased some 330 suits to 150 hospitals, welfare and other facilities in Japan since 2010, at 178,000 yen ($1,950) per suit per year.

"It is very significant that Japan has obtained this certification before others in the world," said Yoshiyuki Sankai, the head of Cyberdyne.

The company is unrelated to the firm of the same name responsible for the cyborg assassin played by Arnold Schwarzenegger in the 1984 film “The Terminator”.

"This is a first step forward for Japan, the great robot nation, to send our message to the world about robots of the future," said Sankai, who is also a professor at Tsukuba University.

A different version of HAL — coincidentally the name of the evil supercomputer in Stanley Kubrick’s “2001: A Space Odyssey” — has been developed for workers who need to wear heavy radiation protection as part of the clean-up at the crippled Fukushima nuclear plant.

Industrial robots have long been used in Japan, and robo-suits are gradually making inroads into hospitals and retirement homes.

But critics say the government has been slow in creating a safety framework for such robots in a country whose rapidly-ageing population is expected to enjoy ever longer lives.

Japan to field test rehabilitation robots

Ten hospitals in Japan are set to begin testing the use of a robot known as “Robot Suit HAL” starting next month. The purpose of the test will be to determine whether use of the robot is beneficial to patients needing physical therapy to regain normal use of their legs.

When people experience nerve or muscle damage to their lower backs or legs due to illness, stroke or injury, the normal course of treatment involves undergoing physical therapy. Doing so causes the body to slowly repair the damage that has been done. In order for it to work however, the parts of the body that work properly have to coax the parts that do not into action, a laborious and quite often painful process. For this reason, professional physical therapists assist patients with the process to ensure that all of the body parts are exercised and to offer emotional support. But such experts can only help so much, and for that reason, robots have been developed to help. The thinking is that because they are sensor based and lack emotional involvement in the process, robots are likely to do a better job.

The Robot Suit HAL (Hybrid Assistive Limb) has been designed and built by Cyberdyne Inc. with assistance from researchers around the country. It’s described by its makers as a cyborg-type robot meant to supplement human muscles or to assist in their rehabilitation. Its part handrail, part sensor and part hydraulically controlled machinery. A patient stands between two handrails, holding on, while sensors are affixed to the skin of the legs. The sensors pick up nerve signals which are sent to an onboard computer. Those signals are then converted to action by small motors and power units that cause the muscle to be worked in the same way it would be were the person’s body able to move it on their own. The end result is a direct connection between nerve signals and movement, which the researchers believe, will result in faster and perhaps better recovery for the patient.

Initial testing will involve 30 volunteer patients. Representatives for Cyberdyne have also announced that the company is in the process of making arrangements for testing the robot in hospitals in Europe as well.

Innovative system for the rehabilitation of people with brain damage

The Biomechanics Institute of Valencia (IBV) is currently taking part in the European project WALKX with the aim of developing an innovative rehabilitation system to improve the quality of life of people who have suffered brain damage. This system will allow home rehabilitation and improve patient’s autonomy.

WALKX is a two-year research project for the benefit of small and medium sized enterprises (SMEs), co-funded by the European Commission through the Seventh Framework Programme.

The user friendly walking training device the partners are designing will support the patient in raising from sitting to standing position and enable the patient to perform walking training and improve his/her manoeuvrability. “An upper body stabilizing and controllable supporting vest will be developed. Early in the rehabilitation process it will be used under supervision of a therapist, but with greatly reduced need for physical support from the therapists. This is intended to reduce the need for help from others and increase freedom of movement and personal autonomy of the patient”, said Ignacio Bermejo, Market Innovation Director at IBV.

One of the novelties of this device consists of a vest with attachment points on the patient’s waist in order to regulate the mobility of the trunk. Also, the device will be modular and low cost. The role of IBV in this initiative has been to define the design specifications and preclinical testing to validate the prototype. Preclinical tests are done in collaboration with the Department of Physical Medicine and Rehabilitation at the Hospital Universitari i Politècnic La Fe of Valencia.

The project is coordinated by the Norwegian company Made for Movement Group. Besides Biomechanics Institute, other members of the consortium are Innovatsiooni Eesti Instituut (Estonia), INNORA ROBOTICS (Greece), Newtrim and MCT (UK), ENIX (France), Motus (Italy) and MOBILE ROBOTICS SWEDEN (Sweden).

Stroke (cerebrovascular accident) is the most common cause of adult disability in Europe. Roughly 75% of victims survive, but about half of these lose the ability to live independently in their own home. As strokes often result in long term disability rather than death, the rehabilitation and hospitalisation represent a major economic burden for the EU of about €34 Bn annually. Currently, the annual incidence is approximately 2 per 1,000 inhabitants in the EU, and the number is predicted to double over the next 50 years due to the aging of the population.

SMART Arm helps stroke survivors recover faster

A non-robotic device that helps stroke survivors regain upper limb movement is expected to be commercially available in Australia within the next 12 months.

Sensory-Motor Active Rehabilitation Training Arm (SMART Arm) is a device developed by researchers from The University of Queensland and James Cook University.

The device enables stroke survivors with upper limb weakness to drive their own rehabilitation through feedback on performance via an interactive computer program and incremental increases in load and reaching range.

Video games can be good for your health

Dr. Penelope McNulty, a neurophysiologist at Neuroscience Research Australia, will present new data that shows the Wii is an effective rehabilitation tool at an international conference of the Society of Electrophysiology and Kinesiology in Brisbane on 20 July.

Dr. McNulty’s data shows that an intensive, two-week training program based on the Wii can result in significant improvements in the way stroke patients are able to use their limbs, even for people that had a stroke many years ago.

“It was previously thought that the movement and function stroke patients had at the time they left hospital was the only recovery they would make,” says Dr. McNulty.

“But we have worked with people who have had strokes one month to 21 years ago, and excitingly, they all improve,” she added.

There are over 60,000 strokes in Australia each year and there is a crucial need to improve rehabilitation methods because this is the only method known to restore movement in stroke-affected limbs.

“The Wii is inexpensive, easy to use and, very importantly, fun. This type of rehabilitation motivates participants to actually complete their therapy, which is essential for maximum recovery,” Dr. McNulty says.

“Everyone notices improvements not just using the Wii, but in activities they do every day, such as opening a door or using a fork,” Dr. McNulty concluded.