Posts Tagged Non-invasive

[BLOG POST] PathMaker Neurosystems – Publication of First Clinical Trial Results for MyoRegulator® Device for Non-Invasive Treatment of Spasticity

PathMaker Neurosystems Inc. (“PathMaker”), a clinical-stage bioelectronic medicine company developing breakthrough non-invasive systems for the treatment of patients with spasticity and paralysis has announced the first publication of clinical trial results for its MyoRegulator® device for the non-invasive treatment of spasticity. Published in Bioelectronic Medicine, the results provide the first clinical evidence using MyoRegulator to treat upper extremity spasticity in subjects with chronic stroke. MyoRegulator is an investigational medical device and is limited by US Federal law to investigational use only.

Spasticity is a chronic condition characterised by painful muscle contractions and is common in patients suffering from stroke, cerebral palsy, multiple sclerosis, spinal cord injury, traumatic brain injury and other neurological disorders. Management of spasticity is a difficult challenge and is currently managed primarily by pharmacological agents and injected botulinum neurotoxins, and there is tremendous unmet medical need.  MyoRegulator is a first-in-class non-invasive device based on PathMaker’s proprietary DoubleStim™ technology (combining anodal trans-spinal direct current stimulation (tsDCS) and peripheral nerve direct current stimulation (pDCS)), which provides simultaneous non-invasive stimulation intended to suppress hyperexcitable spinal neurons involved with spasticity.

“Current pharmacological approaches to managing spasticity have, at best, short-term efficacy, are confounded by adverse effects, and are often unpleasant for the patient,” said co-author Zaghloul Ahmed, Ph.D., Professor and Chairman, Department of Physical Therapy and Professor, Center for Developmental Neuroscience, CUNY and Scientific Founder of PathMaker Neurosystems. “The initial study results demonstrate the potential of a novel, non-invasive treatment to reduce spasticity and improve functional recovery in patients with upper motor neuron syndrome after stroke.”

The publication, Non-Invasive Treatment of Patients with Upper Extremity Spasticity Following Stroke Using Paired Trans-spinal and Peripheral Direct Current Stimulation, was authored by researchers at Feinstein Institute for Medical Research at Northwell Health (Manhasset, NY) led by Bruce Volpe, M.D. The study included patients with upper limb hemiparesis and wrist spasticity at least 6 months after their initial stroke in a single-blind, sham-controlled, crossover design study to test whether MyoRegulator treatment reduces chronic upper-extremity spasticity.

Twenty subjects received five consecutive 20-minute daily treatments with sham stimulation followed by a 1-week washout period, then five consecutive 20-minute daily treatments with active stimulation. Subjects were told that the order of active or sham stimulation would be randomized. Clinical and objective measures of spasticity and motor function were collected before the first session of each condition (baseline), immediately following the last session of each condition, and weekly for 5 weeks after the completion of active treatments. The results demonstrated significant group mean reductions from baseline in both Modified Tardieu Scale scores (summed across the upper limb, P<0.05), and in objectively measured muscle resistance at the wrist flexor (P<0.05) following active treatment as compared to following sham treatment. Motor function also improved significantly (measured by the Fugl-Meyer and Wolf Motor Function Test; P<0.05 for both tests) after active treatment, even without additional prescribed activity or training. The effect of the active MyoRegulator treatment was durable for the 5-week follow-up period.

We are highly encouraged by these clinical results which demonstrate the potential of MyoRegulator to improve outcomes for patients suffering from spasticity, without the need for surgery or drugs. Building on these results and our ongoing clinical trial in Europe, we expect to initiate a US multi-center, pivotal, double-blind clinical trial supported by the National Institute of Neurological Disorders and Stroke (NINDS) in early 2020.

Nader Yaghoubi, M.D., Ph.D., President and Chief Executive Officer of PathMaker

 

About PathMaker Neurosystems Inc.

PathMaker Neurosystems is a clinical stage bioelectronic medicine company developing breakthrough non-invasive systems for the treatment of patients with chronic neuromotor conditions. With offices in Boston (US) and Paris (France), we are collaborating with world-class institutions to rapidly bring to market disruptive products for treating spasticity, paralysis and muscle weakness. In January 2019, we announced a collaboration and distribution agreement with WeHealth Digital Medicine to commercialise the MyoRegulator® device worldwide, excluding US and Japan territories retained by PathMaker.  More than 48 million patients in the US, Europe and China suffer disabilities due to stroke, cerebral palsy, multiple sclerosis, spinal cord injury, traumatic brain injury, Parkinson’s disease and other neurological disorders. At PathMaker, we are opening up a new era of non-invasive neurotherapy for patients suffering from chronic neuromotor conditions. For more information, please visit the company website at www.pmneuro.com.

Source: PathMaker Neurosystems Inc.

via PathMaker Neurosystems – Publication of First Clinical Trial Results for MyoRegulator® Device for Non-Invasive Treatment of Spasticity | ACNR | Online Neurology Journal

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[WEB PAGE] Results from MyoRegulator for Spasticity Trial Published

myoregulator

Results from a clinical trial testing the MyoRegulator device for the non-invasive treatment of spasticity, published recently in Bioelectronic Medicine, suggest evidence for using MyoRegulator to treat upper extremity spasticity in subjects with chronic stroke, PathMaker Neurosystems Inc announces.

PathMaker Neurosystems Inc is a clinical-stage bioelectronic medicine company that develops non-invasive systems for the treatment of patients with spasticity and paralysis. The MyoRegulator is an investigational medical device and is limited by US Federal law to investigational use only.

The device is based on PathMaker’s proprietary DoubleStim technology (combining anodal trans-spinal direct current stimulation (tsDCS) and peripheral nerve direct current stimulation (pDCS)), which provides simultaneous non-invasive stimulation intended to suppress hyperexcitable spinal neurons involved with spasticity, the company explains in a media release.

“Current pharmacological approaches to managing spasticity have, at best, short-term efficacy, are confounded by adverse effects, and are often unpleasant for the patient,” said co-author Zaghloul Ahmed, PhD, professor and chairman, Department of Physical Therapy and Professor, Center for Developmental Neuroscience, CUNY and Scientific Founder of PathMaker Neurosystems.

“The initial study results demonstrate the potential of a novel, non-invasive treatment to reduce spasticity and improve functional recovery in patients with upper motor neuron syndrome after stroke.”

The single-blind, sham-controlled, crossover design study, authored by researchers at Feinstein Institute for Medical Research at Northwell Health (and led by Bruce Volpe, MD, included patients with upper limb hemiparesis and wrist spasticity at least 6 months after their initial stroke to test whether MyoRegulator treatment reduces chronic upper-extremity spasticity.

Twenty subjects received five consecutive 20-minute daily treatments with sham stimulation followed by a 1-week washout period, then five consecutive 20-minute daily treatments with active stimulation. Subjects were told that the order of active or sham stimulation would be randomized.

Clinical and objective measures of spasticity and motor function were collected before the first session of each condition (baseline), immediately following the last session of each condition, and weekly for 5 weeks after the completion of active treatments.

The results demonstrated significant group mean reductions from baseline in both Modified Tardieu Scale scores (summed across the upper limb, P<0.05), and in objectively measured muscle resistance at the wrist flexor (P<0.05) following active treatment as compared to following sham treatment.

Motor function also improved significantly (measured by the Fugl-Meyer and Wolf Motor Function Test; P<0.05 for both tests) after active treatment, even without additional prescribed activity or training. The effect of the active MyoRegulator treatment was durable for the 5-week follow-up period, the release continues.

“We are highly encouraged by these clinical results which demonstrate the potential of MyoRegulator to improve outcomes for patients suffering from spasticity, without the need for surgery or drugs,” says Nader Yaghoubi, MD, PhD, president and chief executive officer of PathMaker.

“Building on these results and our ongoing clinical trial in Europe, we expect to initiate a US multi-center, pivotal, double-blind clinical trial supported by the National Institute of Neurological Disorders and Stroke (NINDS) in early 2020.”

[Source: PathMaker Neurosystems Inc]

 

via Results from MyoRegulator for Spasticity Trial Published – Rehab Managment

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[WEB SITE] Medical Device as Post-Stroke Spasticity Reducer Shows Promise

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An investigational, non-invasive medical device shows promise as a possible treatment for spasticity in patients who have experienced a stroke, Feinstein Institutes for Medical Research scientists report.

Their study, published in Springer Nature’s Bioelectronic Medicine, suggests that trans-spinal direct current stimulation and peripheral nerve direct current stimulation significantly reduced upper limb spasticity in participants who experienced a stroke.

Spasticity is a residual inability of the brain to control muscle tone. It increases muscle stiffness, which inhibits movement of the hands, arms, and legs; can affect the face and throat; and sometimes causes pain.

Efforts to treat upper limb spasticity have focused on intensive, repetitive, activity-dependent learning; however, it is common to experience residual spasticity despite aggressive therapy. When spasticity continues to worsen and causes pain, the standard-of-care is botox (botulinum toxin) injection, according to a media release from Feinstein Institutes for Medical Research.

“Spasticity is a persistent and common inhibitor of movement in patients with chronic stroke, and it has been a great hurdle as we continue to use intensive training to assist motor recovery,” says Bruce T. Volpe, MD, professor at the Feinstein Institutes and lead author of the paper, in the release.

“The surprise in these clinical results were the improved motor functions that apparently occurred with the focused treatment only of spasticity. We are eager to start a trial that couples motor training and anti-spasticity treatment.”

The treatment involves passing a direct electrical current across the spinal cord with a skin surface electrode, known as trans-spinal direct current stimulation (tsDCS), and adding a peripheral direct current stimulation (pDCS) in the paralyzed upper limb. There are additional benefits to patients when tsDCS is combined with pDCS.

Volpe, along with a team that includes Johanna Chang, MS, Alexandra Paget-Blanc, BS, and Maira Saul, MD, employed this device in patients with chronic stroke and hemiparesis to test whether treatment would decrease upper limb spasticity. The trial was a single-blind cross-over design study.

Twenty six participants were treated with five consecutive days of 20 minutes of active, paired tsDCS+pDCS. The participants received both active and sham stimulation conditions, but were not told the order of stimulation.

The device used in the trial was PathMaker Neurosystems Inc’s MyoRegulator, a non-invasive device designed to provide simultaneous, non-invasive stimulation intended to suppress hyperexcitable spinal neurons involved with spasticity.

The results demonstrated that the active treatment condition significantly reduced upper limb spasticity for up to five weeks and these patient responders saw significant improvements in motor function, the release explains.

[Source(s): Feinstein Institutes for Medical Research, PR Newswire]

 

via Medical Device as Post-Stroke Spasticity Reducer Shows Promise – Rehab Managment

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[WEB SITE] How to help patients recover after a stroke

stroke
Credit: CC0 Public Domain

The existing approach to brain stimulation for rehabilitation after a stroke does not take into account the diversity of lesions and the individual characteristics of patients’ brains. This was the conclusion made by researchers of the Higher School of Economics (HSE University) and the Max Planck Institute of Cognitive Sciences in their article, “Predicting the Response to Non-Invasive Brain Stimulation in Stroke.”

Among the most common causes of death worldwide,  ranks second only to myocardial infarction (heart attack). In addition, a stroke is also a chronic disease that leaves patients disabled for many years.

In , non-invasive neuromodulation methods such as electric and magnetic stimulation of various parts of the nervous system have been increasingly used to rehabilitate patients after a stroke. Stimulation selectively affects different parts of the , which allows you to functionally enhance activity in some areas while suppressing unwanted processes in others that impede the restoration of brain functions. This is a promising mean of rehabilitation after a stroke. However, its results in patients remain highly variable.

The study authors argue that the main reason for the lack of effectiveness in neuromodulation approaches after a stroke is an inadequate selection of patients for the application of a particular brain stimulation technique.

According to the authors, the existing approach does not take into account the diversity of lesions after a stroke and the variability of individual responses to brain stimulation as a whole. Researchers propose two criteria for selecting the optimal brain  strategy. The first is an analysis of the interactions between the hemispheres. Now, all patients, regardless of the severity of injury after a stroke, are offered a relatively standard treatment regimen. This approach relies on the idea of interhemispheric competition.

“For a long time, it was believed that when one hemisphere is bad, the second, instead of helping it, suppresses it even more,” explains Maria Nazarova, one of the authors of the article and a researcher at the HSE Institute of Cognitive Neurosciences. “In this regard, the suppression of the activity of the “unaffected” hemisphere should help restore the affected side of the brain. However, the fact is that this particular scheme does not work in many  after a stroke. Each time it is necessary to check what the impact of the unaffected hemisphere is—whether it is suppressive or activating.”

The second criterion, scientists call the neuronal phenotype. This is an individual characteristic of the activity of the brain, which is “as unique to each person as their fingerprints.” Such a phenotype is determined, firstly, by the ability of the brain to build effective structural and functional connections between different areas (connectivity). And, secondly, the individual characteristics of neuronal dynamics, including its ability to reach a . This is the state of the neuronal system in which it is the most plastic and capable of change.

Only by taking these criteria into account, the authors posit, can neuromodulation methods be brought to a new level and be effectively used in clinical practice. To do this, it is necessary to change the paradigm of the universal approach and select methods based on the individual characteristics of the brain of a particular person and the course of his or her disease.


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How electrical stimulation reorganizes the brain

 

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[NEWS] Brain-controlled, non-invasive muscle stimulation allows chronic paraplegics to walk

Brain-controlled, non-invasive muscle stimulation allows chronic paraplegics to walk again and exhibit partial motor recovery

IMAGE

IMAGE: THE NON-INVASIVE CLOSED-LOOP NEUROREHABILITATION PROTOCOL: I) EEG: ELECTROENCEPHALOGRAPHY, NON-INVASIVE BRAIN-RECORDING. II) BRAIN-MACHINE INTERFACE: REAL-TIME DECODING OF MOTOR INTENTIONS. III) THE LEFT OR RIGHT LEG MUSCLES ARE STIMULATED TO TRIGGER THE… view more 
CREDIT: WALK AGAIN PROJECT – ASSOCIAÇÃO ALBERTO SANTOS DUMONT PARA APOIO À PESQUISA

In another major clinical breakthrough of the Walk Again Project, a non-profit international consortium aimed at developing new neuro-rehabilitation protocols, technologies and therapies for spinal cord injury, two patients with paraplegia regained the ability to walk with minimal assistance, through the employment of a fully non-invasive brain-machine interface that does not require the use of any invasive spinal cord surgical procedure. The results of this study appeared on the May 1 issue of the journal Scientific Reports.

The two patients with paraplegia (AIS C) used their own brain activity to control the non-invasive delivery of electrical pulses to a total of 16 muscles (eight in each leg), allowing them to produce a more physiological walk than previously reported, requiring only a conventional walker and a body weight support system as assistive devices. Overall, the two patients were able to produce more than 4,500 steps using this new technology, which combines a non-invasive brain-machine interface, based on a 16-channel EEG, to control a multi-channel functional electrical stimulation system (FES), tailored to produce a much smoother gait pattern than the state of the art of this technique.

“What surprised us was that, in addition to allowing these patients to walk with little help, one of them displayed a clear motor improvement by practicing with this new approach. Patients required approximatively 25 sessions to master the training before they were able to walk using this apparatus,” said Solaiman Shokur one of the authors of the study.

The two patients that used this new rehabilitation approach had previously participated in the long-term neurorehabilitation study carried out using the Walk Again Project Neurorehabilitation (WANR) protocol. As reported in a recent publication from the same team (Shokur et al., PLoS One, Nov. 2018), all seven patients who participated in that protocol for a period of 28 months improved their clinical status, from complete paraplegia (AIS A or B, meaning no motor functions below the level of the injury, according to the ASIA classification) to partial paraplegia (AIS C, meaning partial recovery of sensory and motor function below the injury level). This significant neurological recovery included major clinical improvements in sensory discrimination (tactile, nociception, vibration, and pressure), voluntary motor control of abdomen and leg muscles, and important gains in autonomic control, such as bladder, bowel, and sexual functions.

“The last two studies published by the Walk Again Project clearly indicate that partial neurological and functional recovery can be induced in chronic spinal cord injury patients by combining multiple non-invasive technologies that are based around the concept of using a brain-machine interface to control different types of actuators, like virtual avatars, robotic walkers, or muscle stimulating devices, to allow the total involvement of patients in their own rehabilitation routine,” said Miguel Nicolelis, scientific director of the Walk Again Project and one of the authors of the study.

In a recent report by another group, one AIS C and two AIS D patients were able to walk thanks to the employment of an invasive method for spinal cord electrical stimulation, which required a spinal surgical procedure. In contrast, in the present study two AIS C patients – which originally were AIS A (see Supplemental Material below)- and a third AIS B subject, who recently achieved similar results, were able to regain a significant degree of autonomous walking without the need for such invasive treatments. Instead, these patients only received electrical stimulation patterns delivered to the skin surface of their legs, so that a total of eight muscles in each limb could be electrically stimulated in a physiologically accurate sequence. This was done in order to produce a smoother and more natural pattern of locomotion.

“Crucial for this implementation was the development of a closed-loop controller that allowed real-time correction of the patients’ walking pattern, taking into account muscle fatigue and external perturbations, in order to produce a predefined gait trajectory. Another major component of our approach was the use of a wearable haptic display to deliver tactile feedback to the patients´ forearms in order to provide them with a continuous source of proprioceptive feedback related to their walking,” said Solaiman Shokur.

To control the pattern of electrical muscle stimulation in each leg, these patients utilized an EEG-based brain-machine interface. In this setup, patients learned to alternate the generation of “stepping motor imagery” activity in their right and left motor cortices, in order to create alternated movements of their left and right legs.

According to the authors, the patients exhibited not only “less dependency on walking assistance, but also partial neurological recovery, with substantial rates of motor improvement in one of them.” The improvement in motor control in this last AIS C patient was 9 points in the lower extremity motor score (LEMS), which was comparable with that observed using invasive spinal cord stimulation.

Based on the results obtained over the past 5 years, the WAP now intends to combine all its neurorehabilitation tools into a single integrated, non-invasive platform to treat spinal cord injury patients. This platform will allow patients to begin training soon after the injury occurs. It will also allow the employment of a multi-dimensional integrated brain-machine interface capable of simultaneously controlling virtual and robotic actuators (like a lowerlimb exoskeleton), a multi-channel non-invasive electrical muscle stimulation system (like the FES used in the present study), and a novel non-invasive spinal cord stimulation approach. In this final configuration, this WAP platform will incorporate all these technologies together in order to maximize neurological and functional recovery in the shortest possible time, without the need of any invasive procedure.

According to Dr. Nicolelis, “there is no silver bullet to treat spinal cord injuries. More and more, it looks like we need to implement multiple techniques simultaneously to achieve the best neurorehabilitation results. In this context, it is also imperative to consider the occurrence of cortical plasticity as a major component in the planning of our rehabilitation approach.”

###

The other authors of this paper are Aurelie Selfslagh, Debora S.F. Campos, Ana R. C. Donati, Sabrina Almeida, Seidi Y. Yamauti, Daniel B. Coelho and Mohamed Bouri. This project was developed through a collaboration between the Neurorehabilitation Laboratory of the Associação Alberto Santos Dumont para Apoio à Pesquisa (AASDAP), the headquarters of the Walk Again Project, the Biomechanics and Motor Control Laboratory at the Federal University of ABC (UFABC), and the Laboratory of Robotic System at the Swiss Institute of Technology of Lausanne (EPFL). It was funded by a grant from the Brazilian Financing Agency for Studies and Projects (FINEP) 01.12.0514.00, Ministry of Science, Technology, Innovation and Communications (MCTIC), to AASDAP.

Supplemental Material:

https://www.youtube.com/watch?v=AZbQeuJiSOI

Supporting Research Studies:

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0206464

https://www.nature.com/articles/s41598-019-43041-9

 

via Brain-controlled, non-invasive muscle stimulation allows chronic paraplegics to walk | EurekAlert! Science News

 

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[NEWS] Focused ultrasound offers potential new epilepsy treatment

29 Jan 2019 Tami Freeman
Clinical trial
Researchers at the Ohio State University College of Medicine are studying how well focused ultrasound can treat medication-refractory lobe focal onset epilepsy. (Courtesy: Ohio State University)

Focused ultrasound treatments use multiple ultrasound beams focused deep within the body to provide non-invasive, targeted therapy for a wide range of clinical applications. Now, researchers at The Ohio State University College of Medicine have begun a clinical trial investigating the use of transcranial focused ultrasound to control a specific type of epilepsy in which seizures are not controlled by medication.

The study will enrol up to 10 patients with medication-refractory lobe focal onset epilepsy. Patients will receive MR-guided focused ultrasound through an intact skull to ablate tissue deep in the brain. The treatment works by passing 1024 ultrasound beams through the scalp, skull and brain tissue (without causing any harm) until they converge at a focal point to ablate a specific part of the brain involved in epilepsy.

“We’re pursuing this clinical trial because we know there’s a large unmet clinical need. More than 20 million people worldwide live with uncontrollable seizures because no available treatment works for them,” explains neurosurgeon Vibhor Krishna, who is leading the study. “Our goals are to test the safety of this procedure and study changes in seizure frequency in these patients.”

Earlier this month, a 58-year-old man became the first patient to be treated with focused ultrasound for epilepsy at Ohio State. During the three-hour surgery in an intraoperative MRI-surgical suite, he remained awake and alert, providing real-time feedback to the treatment team. His feedback helped the team safely ablate the brain region involved in spread of his epilepsy without causing undesirable side effects.

After treatment, the research team plan to monitor all the patients closely for one year. They will use neurological exams and neuro-psychological exams to assess language, memory and executive functioning.

“This is an important step in the evolution of focused ultrasound as a mainstream therapy for disorders affecting the brain,” said Neal Kassell, founder and chairman of the Focused Ultrasound Foundation, which is funding the clinical trial. “Ultimately, the results of this study could lead to new, more effective therapies for certain patients with epilepsy.”

 

 

via Focused ultrasound offers potential new epilepsy treatment – Physics World

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[Abstract] Cranial nerve non-invasive neuromodulation improves gait and balance in stroke survivors: A pilot randomised controlled trial

First page of article

Cranial nerve non-invasive neuromodulation (CN-NINM) is delivered using a Portable Neuromodulation Stimulation (PoNS™) device that stimulates two cranial nerve nuclei (trigeminal and facial nerve nuclei) using electrodes embedded in a mouthpiece that rests on the tongue. Danilov and colleagues reported that prolonged and repetitive (20 minutes or more) tongue stimulation coupled with specific training of balance and gait can initiate long-lasting neuronal reorganization that can be measured in participants’ behaviour [1].

via Cranial nerve non-invasive neuromodulation improves gait and balance in stroke survivors: A pilot randomised controlled trial – Brain Stimulation: Basic, Translational, and Clinical Research in Neuromodulation

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[ARTICLE] Brain Computer Interface issues on hand movement – Full Text

January 2018

Abstract

This paper focuses on the Brain Computer Interface (BCI) application and its issues. Further the attempt was made to implement left and right hand movement classification after removal of the artifacts in the acquired signals of the various hand movements.

 

1. Introduction

The Brain Computer Interface (BCI) involves a combination of the brain and device both sharing an interface to enable communication channel between the brain and an object that have to be controlled externally. The human brain has innumerable neurons which are connected to each other for transmission of impulses. As an electrode chip is implemented into the brain via surgical methodology the electrical signals produced by the neurons are transmitted to the computer which then translates the signals into data. These data are interpreted to control a computer device. In 2013, Lebedev successfully coupled the brains of two rats making use of an interface to enable direct sharing of information (Pais-Vieira et al., 2013). Minute fluctuations in voltages between neurons are measured and signals are amplified to produce graphs. While the Invasive BCIs focus on direct implementation into the grey matter of the brain to produce the highest quality of signals by neurosurgery, Non Invasive BCIs make use of techniques like Electroencephalography (EEG), Magneto Encephalography (MEG) and function Magnetic Resonance Imaging (fMRI). EEG techniques experience placing of electrodes on the scalp accompanied by a conductive gel or paste. Many systems are known to use electrodes which are attached to separate wires. Over the years, BCI has been instrumental in developing intelligent relaxation devices, providing enhanced control of devices like wheelchairs and vehicles, controlling robots and computer cursors and providing an additional channel of control in computer games. Bionic eyes have been known to restore sight for people having vision loss (Krishnaveni et al., 2012).

Considering the case of a motor imagery which refers to a mental process wherein an individual replicates an action. Thus, a mental representation of movement prevails without an actual body movement. Imagination efficiency is hard to control. Hence controlling EEG enables an individual to communicate despite the inability to control voluntary muscles. Interface substitute for nerves and muscles and the signals are incorporated into the hardware and software to be translated into physical actions. EEG based BCIs can record and classify EEG changes through different types of motor imagery like imagination of right and left hand and activity, consequently motor imagery as means to enhance motor function and motor learning. It has made a significant contribution in the field of neurological rehabilitation, cognitive neuroscience and cognitive psychology. Clinical applications have procured a great deal of aid from motor imagery ranging from enhancing mobility and locomotion to reduce neuropathic pain (Malouin and Richards, 2013). Analysis and interception of data are challenging as EEG signals are vulnerable to varying fluctuations often termed as noise. Various strategies have been devised for prevention and removal of noise. In this paper, we apply Butterworth filter mechanism to eliminate noise from the signals to enhance the data quality. Besides we concentrate on feature extraction to transform raw signals into informative signals. We make use of Support Vector Machine for the same. Feature extraction contributes significantly in image processing.

A step by step process involved in Brain Computer Interface system is shown in the Fig. 1. Signal is acquired through various means such as invasive (ECog, Neurosurgery) and Non-invasive (EEG, fMRI, MEG) techniques. The channel selection is one of the important considerations since most of the EEG channel represent redundant information (Sleight et al., 2009).
Process involved in brain computing interface system

Figure 1. Process involved in brain computing interface system.

Fig. 2 shows the EEG channel placement on the human scalp. Each scalp electrode is located at the brain centres. In 2001 Pfurtscheller (Wolpaw, 2002) identified that many of the neural activity related to fist movements are found in channels C3, C4 and Cz as shown in Fig. 2 B. F7 is for rational activities, Fz is for intentional and motivational data, P3, P4 and Pz contain perception and differentiation, T3, T4 is for emotional processes, T5, T6 has memory functions and O1 and O2 contain visualization data.

EEG channel placements on the human scalp (http://static

In order to remove the noise from the obtained signal, any of the suitable filtering techniques may be adopted. Further the extracted data may move for classification phase. […]

Continue —-> Brain Computer Interface issues on hand movement – ScienceDirect

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[ARTICLE] Does non-invasive brain stimulation modify hand dexterity? Protocol for a systematic review and meta-analysis – Full Text

 

Abstract

Introduction Dexterity is described as coordinated hand and finger movement for precision tasks. It is essential for day-to-day activities like computer use, writing or buttoning a shirt. Integrity of brain motor networks is crucial to properly execute these fine hand tasks. When these networks are damaged, interventions to enhance recovery are frequently accompanied by unwanted side effects or limited in their effect. Non-invasive brain stimulation (NIBS) are postulated to target affected motor areas and improve hand motor function with few side effects. However, the results across studies vary, and the current literature does not allow us to draw clear conclusions on the use of NIBS to promote hand function recovery. Therefore, we developed a protocol for a systematic review and meta-analysis on the effects of different NIBS technologies on dexterity in diverse populations. This study will potentially help future evidence-based research and guidelines that use these NIBS technologies for recovering hand dexterity.

Methods and analysis This protocol will compare the effects of active versus sham NIBS on precise hand activity. Records will be obtained by searching relevant databases. Included articles will be randomised clinical trials in adults, testing the therapeutic effects of NIBS on continuous dexterity data. Records will be studied for risk of bias. Narrative and quantitative synthesis will be done.

Strengths and limitations of this study

  • This is a novel systematic review and meta-analysis focusing specifically on dexterity.

  • We use continuous data not dependent on the evaluator or participant.

  • This work will potentially help future evidence-based research and guidelines to refine non-invasive brain stimulation.

Introduction

The hand’s somatotopy is extensively represented in the human motor cortex.1 2 Phylogenetically, this relates to the development of corticomotoneuronal cells that specialise in creating patterns of muscle activity that synergises into highly skilled movements.3 This organised hand-and-finger movement to use objects during a specific task is known as dexterity.4 Evolutionary, dexterity played a pivotal role in human survival and is fundamental to actives of daily living, and hence quality of life.5 6

This precision motor movement relies on integration of information from the cerebral cortex, the spinal cord, several neuromusculoskeletal systems and the external world to coordinate finger force control, finger independence, timing and sequence performance.7 During these tasks, multivoxel pattern decoding shows bilateral primary motor cortex activation (M1), which was responsible for muscle recruitment timing and hand movement coordination.8 9 This is related to motor cortex connectivity through the corpus callosum, to motor regions of the cerebellum and white matter integrity.10–15 Adequate motor output translates into successfully executed tasks, like picking up objects, turning over cards, manipulating cutlery, writing, using computer–hand interfaces like smartphones, playing an instrument and performing many other similarly precise skills.16

These motor tasks are negatively impacted when motor output networks are affected, as seen in stroke or Parkinson’s disease.17 18 Therapeutic interventions that restore these damaged motor networks can be vital to restore fine motor movement after injury occurs. Pharmaceutical approaches often lead to adverse effects such as dyskinesias in Parkinson’s disease. Moreover, even after intensive rehabilitation programmes, only about 5%–20% of patients with stroke fully recover their motor function.19–21 Non-invasive brain stimulation (NIBS) techniques, like transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS), are proposed adjuvant or stand-alone interventions to target these affected areas and improve fine motor function.22 23 Briefly, these NIBS interventions are shown to influence the nervous system’s excitability and modulate long-term plasticity, which may be beneficial to the brain’s recovery of functions after injury.24–27

Fine hand motor ability is not studied as much in previous reviews of NIBS. Specifically, one narrative review focuses on rTMS in affected hand recovery poststroke; however, it does not consider the implications of varying International Classification of Functioning, Disability and Health (ICF) domains, data types and rater dependent outcomes, and its interpretability is limited without quantitative synthesis.28–31 The overarching conclusion was supportive of rTMS for paretic hand recovery, though with limited data to support its regular use, and a pressing need to study individualised patient parameters.28 One meta-analysis had positive and significant results when specifically studying the effects of rTMS on finger coordination and hand function after stroke.32 However, while various meta-analysis, and another systematic review, studied upper-limb movement after NIBS in distinct populations, they did not focus on precise hand function, pooled upper-limb outcomes with hand outcomes and presented mixed results.33–38

Motivated by this gap in the evidence for NIBS in dexterity, we will do a systematic review and meta-analysis of the literature on these brain stimulation technologies using outcomes that focus exactly on manual dexterity. These outcomes will be continuous and not dependent on the participant’s or rater’s observation (ie, they will be measured in seconds, or number of blocks/pegs placed, and not by an individual’s interpretation). They will be comprised of multiple domains as defined by the ICF, providing an appreciation of function rather than only condition or disease.29–31 By focusing on the ICF model, we will be able to study dexterity across a larger sample of studies, NIBS techniques and conditions in order to provide a better understanding of brain stimulation efficacy on hand function in various populations.[…]

Continue —. Does non-invasive brain stimulation modify hand dexterity? Protocol for a systematic review and meta-analysis | BMJ Open

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[ARTICLE] Non-Invasive Brain Stimulation to Enhance Upper Limb Motor Practice Poststroke: A Model for Selection of Cortical Site – Full Text

Motor practice is an essential part of upper limb motor recovery following stroke. To be effective, it must be intensive with a high number of repetitions. Despite the time and effort required, gains made from practice alone are often relatively limited, and substantial residual impairment remains. Using non-invasive brain stimulation to modulate cortical excitability prior to practice could enhance the effects of practice and provide greater returns on the investment of time and effort. However, determining which cortical area to target is not trivial. The implications of relevant conceptual frameworks such as Interhemispheric Competition and Bimodal Balance Recovery are discussed. In addition, we introduce the STAC (Structural reserve, Task Attributes, Connectivity) framework, which incorporates patient-, site-, and task-specific factors. An example is provided of how this framework can assist in selecting a cortical region to target for priming prior to reaching practice poststroke. We suggest that this expanded patient-, site-, and task-specific approach provides a useful model for guiding the development of more successful approaches to neuromodulation for enhancing motor recovery after stroke.

Poststroke Arm Impairment

Upper limb motor impairment following stroke is highly prevalent and often persists even after intensive rehabilitation efforts (14). It is also one of the most disabling of stroke sequela, limiting functional independence and precluding return to work and other roles (5).

Upper extremity motor control relies heavily on input transmitted via the corticospinal tract (CST). The CST descends through the posterior limb of the internal capsule, an area vulnerable to middle cerebral artery stroke and in which CST fibers are densely packed. Thus, even a small lesion in this location can have devastating effects on motor function (69). A loss of voluntary wrist and finger extension is particularly common and appears to be related to the extent of CST damage (10). There is also evidence that those who retain wrist extension and have considerable CST sparing are more likely to be responsive to existing therapies (7811).

However, even individuals who lack voluntary wrist and finger extension often retain some ability to move the shoulder and elbow. Unfortunately, only a few stereotyped movement patterns can be performed and these are often not functional. The combination of shoulder flexion with elbow extension that is required for most functional reaching tasks, for example, is frequently lost. Nevertheless, previous studies have demonstrated that reaching practice with trunk restraint can improve unconstrained reaching ability, even in patients who lack wrist and finger extension (1215). Still, a great deal of time and effort is required and the improvements are relatively small.

Non-Invasive Brain Stimulation

Non-invasive brain stimulation offers a potential method of enhancing the effects of practice and thus giving patients greater returns on their investment of time and effort. Approaches to non-invasive brain stimulation are rapidly expanding but generally fall into two major categories: transcranial magnetic stimulation (TMS) and transcranial electrical stimulation [TES; see Ref. (16) for overview of non-invasive techniques for neuromodulation]. These modalities are applied to the scalp overlying a specific cortical area that is being targeted. The level of spatial specificity varies depending on many factors including the modality used (TMS is generally more precise than TES), the stimulation intensity (higher intensity results in a more widespread effect), and the architecture of the underlying tissue. The excitability of the underlying pool of neurons can be modulated by varying stimulation parameters such as the frequency and temporal pattern of the stimuli. Therefore, stimulation can be used to temporarily inhibit or facilitate the underlying cortical area for a sustained period of time after the stimulation ends (usually 20–40 min). In this way, non-invasive brain stimulation could be used to “prime” relevant cortical areas before a bout of practice, potentially enhancing the effects of practice. However, there is little guidance for how such cortical sites might be selected and in which direction (inhibition or facilitation) their activity should be modulated. Conceptual models that could offer such guidance are considered below.

Mechanistic Models to Guide Neuromodulation

Continue —> Frontiers | Non-Invasive Brain Stimulation to Enhance Upper Limb Motor Practice Poststroke: A Model for Selection of Cortical Site | Neurology

Figure 1. On randomly delivered trials, transcranial magnetic stimulation (TMS) perturbation was applied just after a “Go” cue. The effect of this pre-movement perturbation on the speed of the subsequent reaching movement is expressed relative to that in trials with no TMS perturbation. The amount of slowing due to TMS perturbation of the lesioned vs. non-lesioned hemispheres is shown for patients with good structural reserve (left) and patients with poor structural reserve (right).

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