Posts Tagged plasticity

[Abstract] The Effect of Priming on Outcomes of Task-Oriented Training for the Upper Extremity in Chronic Stroke: A Systematic Review and Meta-analysis

Background. Priming results in a type of implicit memory that prepares the brain for a more plastic response, thereby changing behavior. New evidence in neurorehabilitation points to the use of priming interventions to optimize functional gains of the upper extremity in poststroke individuals. Objective. To determine the effects of priming on task-oriented training on upper extremity outcomes (body function and activity) in chronic stroke.

Methods. The PubMed, CINAHL, Web of Science, EMBASE, and PEDro databases were searched in October 2019. Outcome data were pooled into categories of measures considering the International Classification Functional (ICF) classifications of body function and activity. Means and standard deviations for each group were used to determine group effect sizes by calculating mean differences (MDs) and 95% confidence intervals via a fixed effects model. Heterogeneity among the included studies for each factor evaluated was measured using the I2 statistic.

Results. Thirty-six studies with 814 patients undergoing various types of task-oriented training were included in the analysis. Of these studies, 17 were associated with stimulation priming, 12 with sensory priming, 4 with movement priming, and 3 with action observation priming. Stimulation priming showed moderate-quality evidence of body function. Only the Wolf Motor Function Test (time) in the activity domain showed low-quality evidence. However, gains in motor function and in use of extremity members were measured by the Fugl-Meyer Assessment (UE-FMA). Regarding sensory priming, we found moderate-quality evidence and effect size for UE-FMA, corresponding to the body function domain (MD 4.77, 95% CI 3.25-6.29, Z = 6.15, P < .0001), and for the Action Research Arm Test, corresponding to the activity domain (MD 7.47, 95% CI 4.52-10.42, Z = 4.96, P < .0001). Despite the low-quality evidence, we found an effect size (MD 8.64, 95% CI 10.85-16.43, Z = 2.17, P = .003) in movement priming. Evidence for action observation priming was inconclusive.

Conclusion. Combining priming and task-oriented training for the upper extremities of chronic stroke patients can be a promising intervention strategy. Studies that identify which priming techniques combined with task-oriented training for upper extremity function in chronic stroke yield effective outcomes in each ICF domain are needed and may be beneficial for the recovery of upper extremities poststroke.

via The Effect of Priming on Outcomes of Task-Oriented Training for the Upper Extremity in Chronic Stroke: A Systematic Review and Meta-analysis – Erika Shirley Moreira da Silva, Gabriela Nagai Ocamoto, Gabriela Lopes dos Santos-Maia, Roberta de Fátima Carreira Moreira Padovez, Claudia Trevisan, Marcos Amaral de Noronha, Natalia Duarte Pereira, Alexandra Borstad, Thiago Luiz Russo,

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[Abstract] A Novel Wearable Device for Motor Recovery of Hand Function in Chronic Stroke Survivors

Background. In monkey, reticulospinal connections to hand and forearm muscles are spontaneously strengthened following corticospinal lesions, likely contributing to recovery of function. In healthy humans, pairing auditory clicks with electrical stimulation of a muscle induces plastic changes in motor pathways (probably including the reticulospinal tract), with features reminiscent of spike-timing dependent plasticity. In this study, we tested whether pairing clicks with muscle stimulation could improve hand function in chronic stroke survivors.

Methods. Clicks were delivered via a miniature earpiece; transcutaneous electrical stimuli at motor threshold targeted forearm extensor muscles. A wearable electronic device (WD) allowed patients to receive stimulation at home while performing normal daily activities. A total of 95 patients >6 months poststroke were randomized to 3 groups: WD with shock paired 12 ms before click; WD with clicks and shocks delivered independently; standard care. Those allocated to the device used it for at least 4 h/d, every day for 4 weeks. Upper-limb function was assessed at baseline and weeks 2, 4, and 8 using the Action Research Arm Test (ARAT), which has 4 subdomains (Grasp, Grip, Pinch, and Gross).

Results. Severity across the 3 groups was comparable at baseline. Only the paired stimulation group showed significant improvement in total ARAT (median baseline: 7.5; week 8: 11.5; P = .019) and the Grasp subscore (median baseline: 1; week 8: 4; P = .004).

Conclusion. A wearable device delivering paired clicks and shocks over 4 weeks can produce a small but significant improvement in upper-limb function in stroke survivors.

via A Novel Wearable Device for Motor Recovery of Hand Function in Chronic Stroke Survivors – Supriyo Choudhury, Ravi Singh, A. Shobhana, Dwaipayan Sen, Sidharth Shankar Anand, Shantanu Shubham, Suparna Gangopadhyay, Mark R. Baker, Hrishikesh Kumar, Stuart N. Baker,

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[WEB SITE] Why Your Brain Needs Exercise

Why Your Brain Needs Exercise

Credit: Bryan Christie Design

Why Your Brain Needs Exercise

The evolutionary history of humans explains why physical activity is important for brain health

IN BRIEF

  • It is by now well established that exercise has positive effects on the brain, especially as we age.
  • Less clear has been why physical activity affects the brain in the first place.
  • Key events in the evolutionary history of humans may have forged the link between exercise and brain function.
  • Cognitively challenging exercise may benefit the brain more than physical activity that makes fewer cognitive demands.

 

In the 1990s researchers announced a series of discoveries that would upend a bedrock tenet of neuroscience. For decades the mature brain was understood to be incapable of growing new neurons. Once an individual reached adulthood, the thinking went, the brain began losing neurons rather than gaining them. But evidence was building that the adult brain could, in fact, generate new neurons. In one particularly striking experiment with mice, scientists found that simply running on a wheel led to the birth of new neurons in the hippocampus, a brain structure that is associated with memory. Since then, other studies have established that exercise also has positive effects on the brains of humans, especially as we age, and that it may even help reduce the risk of Alzheimer’s disease and other neurodegenerative conditions. But the research raised a key question: Why does exercise affect the brain at all?

Physical activity improves the function of many organ systems in the body, but the effects are usually linked to better athletic performance. For example, when you walk or run, your muscles demand more oxygen, and over time your cardiovascular system responds by increasing the size of the heart and building new blood vessels. The cardiovascular changes are primarily a response to the physical challenges of exercise, which can enhance endurance. But what challenge elicits a response from the brain?

Answering this question requires that we rethink our views of exercise. People often consider walking and running to be activities that the body is able to perform on autopilot. But research carried out over the past decade by us and others would indicate that this folk wisdom is wrong. Instead exercise seems to be as much a cognitive activity as a physical one. In fact, this link between physical activity and brain health may trace back millions of years to the origin of hallmark traits of humankind. If we can better understand why and how exercise engages the brain, perhaps we can leverage the relevant physiological pathways to design novel exercise routines that will boost people’s cognition as they age—work that we have begun to undertake.

FLEXING THE BRAIN

To explore why exercise benefits the brain, we need to first consider which aspects of brain structure and cognition seem most responsive to it. When researchers at the Salk Institute for Biological Studies in La Jolla, Calif., led by Fred Gage and Henriette Van Praag, showed in the 1990s that running increased the birth of new hippocampal neurons in mice, they noted that this process appeared to be tied to the production of a protein called brain-derived neurotrophic factor (BDNF). BDNF is produced throughout the body and in the brain, and it promotes both the growth and the survival of nascent neurons. The Salk group and others went on to demonstrate that exercise-induced neurogenesis is associated with improved performance on memory-related tasks in rodents. The results of these studies were striking because atrophy of the hippocampus is widely linked to memory difficulties during healthy human aging and occurs to a greater extent in individuals with neurodegenerative diseases such as Alzheimer’s. The findings in rodents provided an initial glimpse of how exercise could counter this decline.

Following up on this work in animals, researchers carried out a series of investigations that determined that in humans, just like in rodents, aerobic exercise leads to the production of BDNF and augments the structure—that is, the size and connectivity—of key areas of the brain, including the hippocampus. In a randomized trial conducted at the University of Illinois at Urbana-Champaign by Kirk Erickson and Arthur Kramer, 12 months of aerobic exercise led to an increase in BDNF levels, an increase in the size of the hippocampus and improvements in memory in older adults.

Other investigators have found associations between exercise and the hippocampus in a variety of observational studies. In our own study of more than 7,000 middle-aged to older adults in the U.K., published in 2019 in Brain Imaging and Behavior, we demonstrated that people who spent more time engaged in moderate to vigorous physical activity had larger hippocampal volumes. Although it is not yet possible to say whether these effects in humans are related to neurogenesis or other forms of brain plasticity, such as increasing connections among existing neurons, together the results clearly indicate that exercise can benefit the brain’s hippocampus and its cognitive functions.

Researchers have also documented clear links between aerobic exercise and benefits to other parts of the brain, including expansion of the prefrontal cortex, which sits just behind the forehead. Such augmentation of this region has been tied to sharper executive cognitive functions, which involve aspects of planning, decision-making and multitasking—abilities that, like memory, tend to decline with healthy aging and are further degraded in the presence of Alzheimer’s. Scientists suspect that increased connections between existing neurons, rather than the birth of new neurons, are responsible for the beneficial effects of exercise on the prefrontal cortex and other brain regions outside the hippocampus.

UPRIGHT AND ACTIVE

With mounting evidence that aerobic exercise can boost brain health, especially in older adults, the next step was to figure out exactly what cognitive challenges physical activity poses that trigger this adaptive response. We began to think that examining the evolutionary relation between the brain and the body might be a good place to start. Hominins (the group that includes modern humans and our close extinct relatives) split from the lineage leading to our closest living relatives, chimpanzees and bonobos, between six million and seven million years ago. In that time, hominins evolved a number of anatomical and behavioral adaptations that distinguish us from other primates. We think two of these evolutionary changes in particular bound exercise to brain function in ways that people can make use of today.

Graphic shows how increased production of the protein BDNF may promote neuron growth and survival in the adult brain.

Credit: Tami Tolpa

[…]

For more, visit —->  Why Your Brain Needs Exercise – Scientific American

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[WEB SITE] Play Therapeutic Games with EDNA to Aid Stroke Rehab

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A new touch-screen therapy tool could accelerate the recovery of patients who have experienced a stroke and change the way rehabilitation is delivered in hospitals and homes, RMIT University researchers suggest in a media release.

Designed for people with acquired brain injuries, EDNA is a digital rehabilitation software that delivers therapy through a series of fun and challenging therapeutic games via a touchscreen device.

Findings from a randomized clinical trial showed stroke patients who incorporated EDNA into their treatment programs experienced an improvement two to three times greater than those who received only conventional therapy, according to the release, from RMIT University.

The digital form of rehabilitation was intended to maintain patient engagement, improving compliance and recovery, says RMIT University lead researcher, Associate Professor Jonathan Duckworth.

“We designed EDNA so that patients could be doing therapy without it feeling like therapy,” he adds.

EDNA features a range of therapeutic games that involve tangible and graspable tools with augmented feedback, promoting brain plasticity to regain motor, cognitive and functional ability.

Performance data is then collected in the cloud, allowing therapists to remotely review the integrated data, monitor recovery and deliver tailored treatment programs.

While the results couldn’t yet be used to predict longer-term recovery, the findings were promising and showed the value of including EDNA as part of a therapy toolkit, Duckworth states.

“EDNA is the first upper-limb brain injury rehabilitation system to integrate clinic and home therapy to monitor recovery, so there’s great potential to transform the industry and improve outcomes for patients.”

The recent clinical trial, published in the Journal of NeuroEngineering and Rehabilitation, involved a specialized table-top touch screen.

A new study is now underway at Sydney’s Prince of Wales hospital using a portable version that allows for increased treatment frequency with independent therapy at home.

Principal investigator and neuropsychologist from the University of Sydney, Dr Jeff Rogers, shares in the release that the innovative technology had delivered benefits for stroke patients that had exceeded expectations.

“We’ve worked closely with patients in testing and designing EDNA to ensure it will actually be used and we’re really happy with the results,” he says.

Study co-author, Professor Peter Wilson from the Australian Catholic University, comments that a home-based therapeutic solution had the potential to reduce the number of weekly hospital visits and aligned with recent trends towards patient-centered rehabilitation.

“Patients can struggle to maintain therapy activities between sessions, so having a portable device to take home and use on their own could increase therapy uptake and speed up recovery,” he says.

[Source(s): RMIT University, MedicalXPRess]

 

via Play Therapeutic Games with EDNA to Aid Stroke Rehab – Rehab Managment

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[VIDEO] Harnessing the Power of Neuroplasticity: The Nuts and Bolts of Better Brains – YouTube

What if your brain at 77 were as plastic as it was at 7? What if you could learn Mandarin with the ease of a toddler or play Rachmaninoff without breaking a sweat? A growing understanding of neuroplasticity suggests these fantasies could one day become reality. Neuroplasticity may also be the key to solving diseases like Alzheimer’s, depression, and autism. In this program, leading neuroscientists discuss their most recent findings and both the tantalizing possibilities and pitfalls for our future cognitive selves.

PARTICIPANTS: Alvaro Pascual-Leone, Nim Tottenham, Carla Shatz

MODERATOR: Guy McKhann

MORE INFO ABOUT THE PROGRAM AND PARTICIPANTS: https://www.worldsciencefestival.com/…

This program is part of the BIG IDEAS SERIES, made possible with support from the JOHN TEMPLETON FOUNDATION.

TOPICS: – Opening film 00:07 – What is neuroplasticity? 03:53 – Participant introductions 04:21 – Structure of the brain 05:21 – Is the brain fundamentally unwired at the start? 07:02 – Why does the process of human brain development seem inefficient? 08:30 – Balancing stability and plasticity 10:43 – Critical periods of brain development 13:01 – Extended human childhood development compared to other animals 14:54 – Stability and. plasticity in the visual system 17:37 – Reopening the visual system 25:13 – Pros and cons of brain plasticity vs. stability 27:28 – Plasticity in the autistic brain 29:55 – What is Transcranial magnetic stimulation (TMS) 31:25 – Phases of emotional development 33:10 – Schizophrenia and plasticity 37:40 – Recovery from brain injury 40:24 – Modern rehabilitation techniques 47:21 – Holy grail of Neuroscience 50:12 – Enhancing memory performance as we age 53:37 – Regulating emotions 57:19

PROGRAM CREDITS: – Produced by Nils Kongshaug – Associate Produced by Christine Driscoll – Opening film written / produced by Vin Liota – Music provided by APM – Additional images and footage provided by: Getty Images, Shutterstock, Videoblocks

This program was recorded live at the 2018 World Science Festival and has been edited and condensed for YouTube.

via Harnessing the Power of Neuroplasticity: The Nuts and Bolts of Better Brains – YouTube

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[WEB SITE] When it Comes to Stroke Recovery, Who You See Matters

(a) Top view of the experiment. A tablet monitor was placed over the participant’s right forearms on the desk in front of them. (b) Diagrammatic view of the experiment from the left. There is a space to open the hand, which made it easier to imagine the opening-clench hand movement. (Photo courtesy of Toshihisa Tanaka, TUAT)

For stroke patients, observing their own hand movements in a video-assisted therapy – as opposed to someone else’s hand – could enhance brain activity and speed up rehabilitation, according to researchers.

The scientists, from Tokyo University of Agriculture and Technology (TUAT), published their findings in IEEE Transactions on Neural Systems and Rehabilitation Engineering.

Brain plasticity, where a healthy region of the brain fulfills the function of a damaged region of the brain, is a key factor in the recovery of motor functions caused by stroke. Studies have shown that sensory stimulation of the neural pathways that control the sense of touch can promote brain plasticity, essentially rewiring the brain to regain movement and senses.

To promote brain plasticity, stroke patients may incorporate a technique called motor imagery in their therapy. Motor imagery allows a participant to mentally simulate a given action by imagining themselves going through the motions of performing that activity. This therapy may be enhanced by a brain-computer interface technology, which detects and records the patients’ motor intention while they observe the action of their own hand or the hand of another person, a media release from Tokyo University of Agriculture and Technology explains.

“We set out to determine whether it makes a difference if the participant is observing their own hand or that of another person while they’re imagining themselves performing the task,” says co-author Toshihisa Tanaka, a professor in the Department of Electrical and Electrical Engineering at TUAT in Japan and a researcher at the RIKEN Center for Brain Science and the RIKEN Center for Advanced Intelligent Project.

The researchers monitored brain activity of 15 healthy right-handed male participants under three different scenarios. In the first scenario, participants were asked to imagine their hand moving in synchrony with hand movements being displayed in a video clip showing their own hand performing the task, together with corresponding voice cues.

In the second scenario, they were asked to imagine their hand moving in synchrony with hand movements being displayed on a video clip showing another person’s hand performing the task, together with voice cues. In the third scenario, the participants were asked to open and close their hands in response to voice cues only.

Using electroencephalography (EEG), brain activity of the participants was observed as they performed each task.

The team found meaningful differences in EEG measurements when participants were observing their own hand movement and that of another person. The findings suggest that, in order for motor imagery-based therapy to be most effective, video footage of a patient’s own hand should be used.

“Visual tasks where a patient observes their own hand movement can be incorporated into brain-computer interface technology used for stroke rehabilitation that estimates a patient’s motor intention from variations in brain activity, as it can give the patient both visual and sense of movement feedback,” Tanaka explains.

[Source(s): Tokyo University of Agriculture and Technology, EurekAlert]

via When it Comes to Stroke Recovery, Who You See Matters – Rehab Managment

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[Abstract] Bilateral Contralaterally Controlled Functional Electrical Stimulation Reveals New Insights Into the Interhemispheric Competition Model in Chronic Stroke

Background. Upper-limb chronic stroke hemiplegia was once thought to persist because of disproportionate amounts of inhibition imposed from the contralesional on the ipsilesional hemisphere. Thus, one rehabilitation strategy involves discouraging engagement of the contralesional hemisphere by only engaging the impaired upper limb with intensive unilateral activities. However, this premise has recently been debated and has been shown to be task specific and/or apply only to a subset of the stroke population. Bilateral rehabilitation, conversely, engages both hemispheres and has been shown to benefit motor recovery. To determine what neurophysiological strategies bilateral therapies may engage, we compared the effects of a bilateral and unilateral based therapy using transcranial magnetic stimulation.

Methods. We adopted a peripheral electrical stimulation paradigm where participants received 1 session of bilateral contralaterally controlled functional electrical stimulation (CCFES) and 1 session of unilateral cyclic neuromuscular electrical stimulation (cNMES) in a repeated-measures design. In all, 15 chronic stroke participants with a wide range of motor impairments (upper extremity Fugl-Meyer score: 15 [severe] to 63 [mild]) underwent single 1-hour sessions of CCFES and cNMES. We measured whether CCFES and cNMES produced different effects on interhemispheric inhibition (IHI) to the ipsilesional hemisphere, ipsilesional corticospinal output, and ipsilateral corticospinal output originating from the contralesional hemisphere.

Results. CCFES reduced IHI and maintained ipsilesional output when compared with cNMES. We found no effect on ipsilateral output for either condition. Finally, the less-impaired participants demonstrated a greater increase in ipsilesional output following CCFES.

Conclusions. Our results suggest that bilateral therapies are capable of alleviating inhibition on the ipsilesional hemisphere and enhancing output to the paretic limb.

 

via Bilateral Contralaterally Controlled Functional Electrical Stimulation Reveals New Insights Into the Interhemispheric Competition Model in Chronic Stroke – David A. Cunningham, Jayme S. Knutson, Vishwanath Sankarasubramanian, Kelsey A. Potter-Baker, Andre G. Machado, Ela B. Plow, 2019

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[Abstract] Bilateral Contralaterally Controlled Functional Electrical Stimulation Reveals New Insights Into the Interhemispheric Competition Model in Chronic Stroke

Background. Upper-limb chronic stroke hemiplegia was once thought to persist because of disproportionate amounts of inhibition imposed from the contralesional on the ipsilesional hemisphere. Thus, one rehabilitation strategy involves discouraging engagement of the contralesional hemisphere by only engaging the impaired upper limb with intensive unilateral activities. However, this premise has recently been debated and has been shown to be task specific and/or apply only to a subset of the stroke population. Bilateral rehabilitation, conversely, engages both hemispheres and has been shown to benefit motor recovery. To determine what neurophysiological strategies bilateral therapies may engage, we compared the effects of a bilateral and unilateral based therapy using transcranial magnetic stimulation.

Methods. We adopted a peripheral electrical stimulation paradigm where participants received 1 session of bilateral contralaterally controlled functional electrical stimulation (CCFES) and 1 session of unilateral cyclic neuromuscular electrical stimulation (cNMES) in a repeated-measures design. In all, 15 chronic stroke participants with a wide range of motor impairments (upper extremity Fugl-Meyer score: 15 [severe] to 63 [mild]) underwent single 1-hour sessions of CCFES and cNMES. We measured whether CCFES and cNMES produced different effects on interhemispheric inhibition (IHI) to the ipsilesional hemisphere, ipsilesional corticospinal output, and ipsilateral corticospinal output originating from the contralesional hemisphere.

Results. CCFES reduced IHI and maintained ipsilesional output when compared with cNMES. We found no effect on ipsilateral output for either condition. Finally, the less-impaired participants demonstrated a greater increase in ipsilesional output following CCFES.

Conclusions. Our results suggest that bilateral therapies are capable of alleviating inhibition on the ipsilesional hemisphere and enhancing output to the paretic limb.

via Bilateral Contralaterally Controlled Functional Electrical Stimulation Reveals New Insights Into the Interhemispheric Competition Model in Chronic Stroke – David A. Cunningham, Jayme S. Knutson, Vishwanath Sankarasubramanian, Kelsey A. Potter-Baker, Andre G. Machado, Ela B. Plow,

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[ARTICLE] Efficacy and Brain Imaging Correlates of an Immersive Motor Imagery BCI-Driven VR System for Upper Limb Motor Rehabilitation: A Clinical Case Report – Full Text

To maximize brain plasticity after stroke, a plethora of rehabilitation strategies have been explored. These include the use of intensive motor training, motor-imagery (MI), and action-observation (AO). Growing evidence of the positive impact of virtual reality (VR) techniques on recovery following stroke has been shown. However, most VR tools are designed to exploit active movement, and hence patients with low level of motor control cannot fully benefit from them. Consequently, the idea of directly training the central nervous system has been promoted by utilizing MI with electroencephalography (EEG)-based brain-computer interfaces (BCIs). To date, detailed information on which VR strategies lead to successful functional recovery is still largely missing and very little is known on how to optimally integrate EEG-based BCIs and VR paradigms for stroke rehabilitation. The purpose of this study was to examine the efficacy of an EEG-based BCI-VR system using a MI paradigm for post-stroke upper limb rehabilitation on functional assessments, and related changes in MI ability and brain imaging. To achieve this, a 60 years old male chronic stroke patient was recruited. The patient underwent a 3-week intervention in a clinical environment, resulting in 10 BCI-VR training sessions. The patient was assessed before and after intervention, as well as on a one-month follow-up, in terms of clinical scales and brain imaging using functional MRI (fMRI). Consistent with prior research, we found important improvements in upper extremity scores (Fugl-Meyer) and identified increases in brain activation measured by fMRI that suggest neuroplastic changes in brain motor networks. This study expands on the current body of evidence, as more data are needed on the effect of this type of interventions not only on functional improvement but also on the effect of the intervention on plasticity through brain imaging.

Introduction

Worldwide, stroke is a leading cause of adult long-term disability (Mozaffarian et al., 2015). From those who survive, an increased number is suffering with severe cognitive and motor impairments, resulting in loss of independence in their daily life such as self-care tasks and participation in social activities (Miller et al., 2010). Rehabilitation following stroke is a multidisciplinary approach to disability which focuses on recovery of independence. There is increasing evidence that chronic stoke patients maintain brain plasticity, meaning that there is still potential for additional recovery (Page et al., 2004). Traditional motor rehabilitation is applied through physical therapy and/or occupational therapy. Current approaches of motor rehabilitation include functional training, strengthening exercises, and range of movement exercises. In addition, techniques based on postural control, stages of motor learning, and movement patterns have been proposed such as in the Bobath concept and Bunnstrom approach (amongst others) (Bobath, 1990). After patients complete subacute rehabilitation programs, many still show significant upper limb motor impairment. This has important functional implications that ultimately reduce their quality of life. Therefore, alternative methods to maximize brain plasticity after stroke need to be developed.

So far, there is growing evidence that action observation (AO) (Celnik et al., 2008) and motor imagery (MI) improve motor function (Mizuguchi and Kanosue, 2017) but techniques based on this paradigm are not widespread in clinical settings. As motor recovery is a learning process, the potential of MI as a training paradigm relies on the availability of an efficient feedback system. To date, a number of studies have demonstrated the positive impact of virtual-reality (VR) based on neuroscientific grounds on recovery, with proven effectiveness in the stroke population (Bermúdez i Badia et al., 2016). However, patients with no active movement cannot benefit from current VR tools due to low range of motion, pain, fatigue, etc. (Trompetto et al., 2014). Consequently, the idea of directly training the central nervous system was promoted by establishing an alternative pathway between the user’s brain and a computer system.

This is possible by using electroencephalography (EEG)-based Brain-Computer Interfaces (BCIs), since they can provide an alternative non-muscular channel for communication and control to the external world (Wolpaw et al., 2002), while they could also provide a cost-effective solution for training (Vourvopoulos and Bermúdez, 2016b). In rehabilitation, BCIs could offer a unique tool for rehabilitation since they can stimulate neural networks through the activation of mirror neurons (Rizzolatti and Craighero, 2004) by means of action-observation (Kim et al., 2016), motor-intent and motor-imagery (Neuper et al., 2009), that could potentially lead to post-stroke motor recovery. Thus, BCIs could provide a backdoor to the activation of motor neural circuits that are not stimulated through traditional rehabilitation techniques.

In EEG-based BCI systems for motor rehabilitation, Alpha (8–12 Hz) and Beta (12–30 Hz) EEG rhythms are utilized since they are related to motor planning and execution (McFarland et al., 2000). During a motor attempt or motor imagery, the temporal pattern of the Alpha rhythms desynchronizes. This rhythm is also named Rolandic Mu-rhythm or the sensorimotor rhythm (SMR) because of its localization over the sensorimotor cortices. Mu-rhythms are considered indirect indications of functioning of the mirror neuron system and general sensorimotor activity (Kropotov, 2016). These are often detected together with Beta rhythm changes in the form of an event-related desynchronization (ERD) when a motor action is executed (Pfurtscheller and Lopes da Silva, 1999). These EEG patterns are primarily detected during task-based EEG (e.g., when the participant is actively moving or imagining movement) and they are of high importance in MI-BCIs for motor rehabilitation.

A meta-analysis of nine studies (combined N = 235, sample size variation 14 to 47) evaluated the clinical effectiveness of BCI-based rehabilitation of patients with post-stroke hemiparesis/hemiplegia and concluded that BCI technology could be effective compared to conventional treatment (Cervera et al., 2018). This included ischemic and hemorrhagic stroke in both subacute and chronic stages of stoke, between 2 to 8 weeks. Moreover, there is evidence that BCI-based rehabilitation promotes long-lasting improvements in motor function of chronic stroke patients with severe paresis (Ramos-Murguialday et al., 2019), while overall BCI’s are starting to prove their efficacy as rehabilitative technologies in patients with severe motor impairments (Chaudhary et al., 2016).

The feedback modalities used for BCI motor rehabilitation include: non-embodied simple two-dimensional tariffs on a screen (Prasad et al., 2010Mihara et al., 2013), embodied avatar representation of the patient on a screen or with augmented reality (Holper et al., 2010Pichiorri et al., 2015), neuromuscular electrical stimulation (NMES) (Kim et al., 2016Biasiucci et al., 2018). and robotic exoskeletal orthotic movement facilitation (Ramos-Murguialday et al., 2013Várkuti et al., 2013Ang et al., 2015). In addition, it has been shown that multimodal feedback lead to a significantly better performance in motor-imagery (Sollfrank et al., 2016) but also multimodal feedback combined with motor-priming, (Vourvopoulos and Bermúdez, 2016a). However, there is no evidence which modalities are more efficient in stroke rehabilitation are.

Taking into account all previous findings in the effects of multimodal feedback in MI training, the purpose of this case study is to examine the effect of the MI paradigm as a treatment for post-stroke upper limb motor dysfunction using the NeuRow BCI-VR system. This is achieved through the acquisition of clinical scales, dynamics of EEG during the BCI treatment, and brain activation as measured by functional MRI (fMRI). NeuRow is an immersive VR environment for MI-BCI training that uses an embodied avatar representation of the patient arms and haptic feedback. The combination of MI-BCIs with VR can reinforce activation of motor brain areas, by promoting the illusion of physical movement and the sense of embodiment in VR (Slater, 2017), and hence further engaging specific neural networks and mobilizing the desired neuroplastic changes. Virtual representation of body parts paves the way to include action observation during treatment. Moreover, haptic feedback is added since a combination of feedback modalities could prove to be more effective in terms of motor-learning (Sigrist et al., 2013). Therefore, the target of this system is to be used by patients with low or no levels of motor control. With this integrated BCI-VR approach, severe cases of stroke survivors may be admitted to a VR rehabilitation program, complementing traditional treatment.

Methodology

Patient Profile

In this pilot study we recruited a 60 years old male patient with left hemiparesis following cerebral infarct in the right temporoparietal region 10 months before. The participant had corrected vision through eyewear, he had 4 years of schooling and his experience with computers was reported as low. Moreover, the patient was on a low dose of diazepam (5 mg at night to help sleep), dual antiplatelet therapy, anti-hypertensive drug and metformin. Hemiparesis was associated with reduced dexterity and fine motor function; however, sensitivity was not affected. Other sequelae of the stroke included hemiparetic gait and dysarthria. Moreover, a mild cognitive impairment was identified which did not interfere with his ability to perform the BCI-VR training. The patient had no other relevant comorbidities. Finally, the patient was undergoing physiotherapy and occupational therapy at the time of recruitment and had been treated with botulinum toxin infiltration 2 months before due to focal spasticity of the biceps brachii.

Intervention Protocol

The patient underwent a 3-weeks intervention with NeuRow, resulting in 10 BCI sessions of a 15 min of exposure in VR training per session. Clinical scales, motor imagery capability assessment, and functional -together with structural- MRI data had been gathered in three time-periods: (1) before (serving as baseline), (2) shortly after the intervention and (3) one-month after the intervention (to assess the presence of long-term changes). Finally, electroencephalographic (EEG) data had been gathered during all sessions, resulting in more than 20 datasets of brain electrical activity.

The experimental protocol was designed in collaboration with the local healthcare system of Madeira, Portugal (SESARAM) and approved by the scientific and ethic committees of the Central Hospital of Funchal. Finally, written informed consent was obtained from the participant upon recruitment for participating to the study but also for the publication of the case report in accordance with the 1964 Declaration of Helsinki.

Assessment Tools

A set of clinical scales were acquired including the following:

1. Montreal Cognitive Assessment (MoCA). MoCA is a cognitive screening tool, with a score range between 0 and 30 (a score greater than 26 is considered to be normal) validated also for the Portuguese population, (Nasreddine et al., 2005).

2. Modified Ashworth scale (MAS). MAS is a 6-point rating scale for measuring spasticity. The score range is 0, 1, 1+, 2, 3, and 4 (Ansari et al., 2008).

3. Fugl-Meyer Assessment (FMA). FMA is a stroke specific scale that assesses motor function, sensation, balance, joint range of motion and joint pain. The motor domain for the upper limb has a maximum score of 66 (Fugl-Meyer et al., 1975).

4. Stroke Impact Scale (SIS). SIS is a subjective scale of the perceived stroke impact and recovery as reported by the patient, validated for the Portuguese population. The score of each domain of the questionnaire ranges from 0 to 100 (Duncan et al., 1999).

5. Vividness of Movement Imagery Questionnaire (VMIQ2). VMIQ2 is an instrument that assess the capability of the participant to perform imagined movements from external perspective (EVI), internal perspective imagined movements (IVI) and finally, kinesthetic imagery (KI) (Roberts et al., 2008).

NeuRow BCI-VR System

EEG Acquisition

For EEG data acquisition, the Enobio 8 (Neuroelectrics, Barcelona, Spain) system was used. Enobio is a wearable wireless EEG sensor with 8 EEG channels for the recording and visualization of 24-bit EEG data at 500 Hz and a triaxial accelerometer. The spatial distribution of the electrodes followed the 10–20 system configuration (Klem et al., 1999) with the following electrodes over the somatosensory and motor areas: Frontal-Central (FC5, FC6), Central (C1, C2, C3, C4), and Central-Parietal (CP5, CP6) (Figure 1A). The EEG system was connected via Bluetooth to a dedicated desktop computer, responsible for the EEG signal processing and classification, streaming the data via UDP through the Reh@Panel (RehabNet Control Panel) for controlling the virtual environment. The Reh@Panel is a free tool that acts as a middleware between multiple interfaces and virtual environments (Vourvopoulos et al., 2013).

FIGURE 1

Figure 1. Experimental setup, including: (A) the wireless EEG system; (B) the Oculus HMD, together with headphones reproducing the ambient sound from the virtual environment; (C) the vibrotactile modules supported by a custom-made table-tray, similar to the wheelchair trays used for support; (D) the visual feedback with NeuRow game. A written informed consent was obtained for the publication of this image.

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Continue —->  Frontiers | Efficacy and Brain Imaging Correlates of an Immersive Motor Imagery BCI-Driven VR System for Upper Limb Motor Rehabilitation: A Clinical Case Report | Frontiers in Human Neuroscience

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[Conference Paper] Modelling of a wearable jacket with sensors and actuators for upper limb rehabilitation

Abstract

Introduction Spinal Cord Injury (SCI) affects a large number of young people and, if left  untreated, can deal irreversible damage to the human body. Several studies have demonstrated the positive impact of physical therapy to the rehabilitation process, promoting neuro-plasticity and thus at least partial restoration of functionality of the body and gait. These studies focus on the implementation of engineered solutions, such as robotic exoskeletons and virtual reality training regimens. The common denominator in most of them is the implementation of some form of Human-Machine Interface (HMI), for the control of these modalities by direct user feedback. These HMIs are based on a plethora of sensor arrays, ranging from direct motion-specific body data, such as Electroencephalography (EEG) and Electromyography (EMG) to more common sensor devices, such as accelerometers and gyroscopes. These sensors can provide direct measurements, tailored to the application at hand and provide the necessary data for the desired functionality. Materials and Methods The proposed device will function as a sensor array for the upper-body, providing live data for muscle activity, through the use of Electromyography (EMG) electrodes, as well as relative joint positioning and rotation, utilizing Inertial Measurement Units (IMUs), for the purpose of monitoring and Augmented Reality (AR) integration. Said motion data will be then used to enhance the users desired movement, through the use of Functional Electronic Stimulation (FES), by providing the necessary impulse to each muscle group, from the measured feedback. The relationship between sensor input and stimulation will allow for reinforcement of the users’ movements, promoting neuroplasticity and ease of movement in the process of neuro-rehabilitation. Furthermore, this modality will act as a platform for several other physiological measurements, such as heart rate and perspiration, essentially creating a functional Body-Area Network (BAN) of sensors. Integration with external motion actuators will be investigated, as a means to provide upper-body support, providing the necessary strength, as a means of easing the rehabilitation process and removing unnecessary stress from the user. Finally, interactions with implanted medical devices will be explored. Such devices could provide telemetry data from inside the body, to be used as a form of direct feedback for the designed Body Area Network (BAN), and the aforementioned stimulation and actuation.

via Modelling of a wearable jacket with sensors and actuators for upper limb rehabilitation

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