The brain's electrical signals enable people without muscle control to physically interact with the world.

Brain-computer interfaces for communication and control

Two people with long-standing tetraplegia use neural interface system-based control of a robotic arm to perform three-dimensional reach and grasp movements. John Donoghue and colleagues have previously demonstrated that people with tetraplegia can learn to use neural signals from the motor cortex to control a computer cursor. Work from another lab has also shown that monkeys can learn to use such signals to feed themselves with a robotic arm. Now, Donoghue and colleagues have advanced the technology to a level at which two people with long-standing paralysis — a 58-year-old woman and a 66-year-old man — are able to use a neural interface to direct a robotic arm to reach for and grasp objects. One subject was able to learn to pick up and drink from a bottle using a device implanted 5 years earlier, demonstrating not only that subjects can use the brain–machine interface, but also that it has potential longevity. Paralysis following spinal cord injury, brainstem stroke, amyotrophic lateral sclerosis and other disorders can disconnect the brain from the body, eliminating the ability to perform volitional movements. A neural interface system1,2,3,4,5 could restore mobility and independence for people with paralysis by translating neuronal activity directly into control signals for assistive devices. We have previously shown that people with long-standing tetraplegia can use a neural interface system to move and click a computer cursor and to control physical devices6,7,8. Able-bodied monkeys have used a neural interface system to control a robotic arm9, but it is unknown whether people with profound upper extremity paralysis or limb loss could use cortical neuronal ensemble signals to direct useful arm actions. Here we demonstrate the ability of two people with long-standing tetraplegia to use neural interface system-based control of a robotic arm to perform three-dimensional reach and grasp movements. Participants controlled the arm and hand over a broad space without explicit training, using signals decoded from a small, local population of motor cortex (MI) neurons recorded from a 96-channel microelectrode array. One of the study participants, implanted with the sensor 5 years earlier, also used a robotic arm to drink coffee from a bottle. Although robotic reach and grasp actions were not as fast or accurate as those of an able-bodied person, our results demonstrate the feasibility for people with tetraplegia, years after injury to the central nervous system, to recreate useful multidimensional control of complex devices directly from a small sample of neural signals.

/pdf/reach-and-grasp-by-people-with-tetraplegia-using-a-neurally-u1xyn3on0d.pdf

Reach and grasp by people with tetraplegia using a neurally controlled robotic arm

Brain-machine interfaces have mostly been used previously to move cursors on computer displays. Now experiments on macaque monkeys show that brain activity signals can control a multi-jointed prosthetic device in real-time. The monkeys used motor cortical activity to control a human-like prosthetic arm in a self-feeding task, with a greater sophistication of control than previously possible. This work could be important for the development of more practical neuro-prosthetic devices in the future. A system where monkeys use their motor cortical activity to control a robotic arm in a real-time self-feeding task, showing a significantly greater sophisitication of control than in previous studies, is demonstrated. This work could be important for the development of more practical neuro-prosthetic devices in the future. Arm movement is well represented in populations of neurons recorded from the motor cortex1,2,3,4,5,6,7. Cortical activity patterns have been used in the new field of brain–machine interfaces8,9,10,11 to show how cursors on computer displays can be moved in two- and three-dimensional space12,13,14,15,16,17,18,19,20,21,22. Although the ability to move a cursor can be useful in its own right, this technology could be applied to restore arm and hand function for amputees and paralysed persons. However, the use of cortical signals to control a multi-jointed prosthetic device for direct real-time interaction with the physical environment (‘embodiment’) has not been demonstrated. Here we describe a system that permits embodied prosthetic control; we show how monkeys (Macaca mulatta) use their motor cortical activity to control a mechanized arm replica in a self-feeding task. In addition to the three dimensions of movement, the subjects’ cortical signals also proportionally controlled a gripper on the end of the arm. Owing to the physical interaction between the monkey, the robotic arm and objects in the workspace, this new task presented a higher level of difficulty than previous virtual (cursor-control) experiments. Apart from an example of simple one-dimensional control23, previous experiments have lacked physical interaction even in cases where a robotic arm16,19,24 or hand20 was included in the control loop, because the subjects did not use it to interact with physical objects—an interaction that cannot be fully simulated. This demonstration of multi-degree-of-freedom embodied prosthetic control paves the way towards the development of dexterous prosthetic devices that could ultimately achieve arm and hand function at a near-natural level.

/pdf/cortical-control-of-a-prosthetic-arm-for-self-feeding-1ethevoxtu.pdf

Cortical control of a prosthetic arm for self-feeding

A brain-computer interface (BCI) is a hardware and software communications system that permits cerebral activity alone to control computers or external devices. The immediate goal of BCI research is to provide communications capabilities to severely disabled people who are totally paralyzed or 'locked in' by neurological neuromuscular disorders, such as amyotrophic lateral sclerosis, brain stem stroke, or spinal cord injury. Here, we review the state-of-the-art of BCIs, looking at the different steps that form a standard BCI: signal acquisition, preprocessing or signal enhancement, feature extraction, classification and the control interface. We discuss their advantages, drawbacks, and latest advances, and we survey the numerous technologies reported in the scientific literature to design each step of a BCI. First, the review examines the neuroimaging modalities used in the signal acquisition step, each of which monitors a different functional brain activity such as electrical, magnetic or metabolic activity. Second, the review discusses different electrophysiological control signals that determine user intentions, which can be detected in brain activity. Third, the review includes some techniques used in the signal enhancement step to deal with the artifacts in the control signals and improve the performance. Fourth, the review studies some mathematic algorithms used in the feature extraction and classification steps which translate the information in the control signals into commands that operate a computer or other device. Finally, the review provides an overview of various BCI applications that control a range of devices.

/pdf/brain-computer-interfaces-a-review-2z42gnpdfy.pdf

Brain Computer Interfaces, a Review

https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(11)61346-9.pdf

Primary brain tumours in adults

UNLABELLED {\it OBJECTIVE } To evaluate the efficacy of pain management in a clinical pathway for rehabilitation after hip and knee arthroplasty, in which scheduled medications are rapidly tapered and prn medications are continued throughout the inpatient stay. {\it STUDY DESIGN } A prospective cross-sectional study. {\it SETTING } General rehabilitation unit of a regional acute rehabilitation center. {\it PATIENTS } Twenty-nine patients admitted consecutively to the rehabilitation unit in three months. {\it OUTCOME MEASURES } Number of pills/day of prn pain medication, pain scores at admission and discharge, frequency of constipation and nausea, Functional Independence Measure (FIM) gain, and length of stay (LOS). {\it RESULTS } For all patients, prn pain medication use was 2.4 pills/day/patient; the mean FIM gain was 22.1; and the average LOS was 9.8 days. In comparison to the Vicodin group, patients on Darvocet N-100 had significantly fewer requests for prn pain medication each day (3.1 vs. 1.1, p < 0.01), significantly better FIM gains better (18.9 vs. 24.1, p < 0.05), and fewer side effects (nausea and constipation). {\it CONCLUSION } Choosing the right pain medication is imperative for achieving optimal efficiency in clinical pathways for orthopedic rehabilitation. In this pilot study, Darvocet N-100 is the preferred narcotic over codeine and its derivatives.

A pilot study of pain management during rehabilitation for hip and knee arthroplasty.

Patients at various stages of human immunodeficiency virus (HIV) infection require rehabilitation services. These patients present problems for each of the disciplines in a rehabilitation team, and all team members must confront the psychosocial and ethical issues involved with the disease. Patients with HIV infection may have polyneuropathy with multisystem involvement, including dysphagia, autonomic dysfunction, respiratory failure, bowel and bladder dysfunction, generalized weakness, a painful sensory neuropathy, and depression. Guidelines are presented for determining if inpatient rehabilitation or other settings are appropriate. Case management is a valuable strategy for the rehabilitation of patients with this complicated disorder.

Human immunodeficiency virus infection and diffuse polyneuropathy. Implications for rehabilitation medicine.

Low back pain (LBP) is a common complaint in the United States, with an incidence of 6.3%-15.4% and yearly recurrence in 54%-90% of patients.1 Trends show more frequent diagnostic testing, opioid use, and surgical intervention as the incidence of LBP increases.2 LBP is defined as pain at and near the lumbosacral region that can vary with physical activity and time. LBP is usually related to pathology of muscles, ligaments, spinal column joints, nerve roots, and the spinal cord. During the assessment of LBP, practitioners must also consider less common causes of pain in that region. For instance, patients with indolent or nighttime pain may have infectious or malignant processes. Referred pain from injuries to pelvic musculature or abdominal contents should be considered, especially following a traumatic event. One of these injuries, which can present as acute low back pain, is rupture of the proximal hamstring tendon. On rare occasion, concomitant LBP, radiculopathy, and hamstring injuries can occur;. This diagnostic challenge is described in the following case.

http://rimed.org/rimedicaljournal/2015/12/2015-12-23-neuro-deren.pdf

Low back pain, radiculopathy, and bilateral proximal hamstring ruptures: a case report.

Delayed diagnosis of concomitant rotator cuff tear and brachial plexopathy in a patient with traumatic brain injury: a case report.

A variety of neurological conditions can lead to disability, pain, and a decline in quality of life. As the American population ages, the prevalence of neurological disability will increase due to conditions such as stroke and Alzheimer’s disease. Recent data show that about 800,000 strokes occur annually in the United States and someone dies of a stroke every four minutes.1 Stroke survivors have to contend with outcomes ranging from mild impairments to total dependence. In the younger population, there is an epidemic of concussion related to sports. Every year about 182,000 football players sustain at least one concussion, primarily in youth (99,000) and high school (80,000) programs, or about 1 in 30 youth players and 1 in 14 high school players. Brain damage at this early stage of life has adverse effects for a long time.2 My perspective on neurological disability is that of a rehabilitation medicine specialist and medical director of the Southern New England Rehabilitation Center (SNERC) and the Sargent Rehabilitation Center (SRC). SNERC follows Medicare criteria for acute inpatient rehabilitation (medical stability, ability to tolerate three hours of therapy/day, goals and potential for progress, etc.); the center treats adults with neurological conditions including strokes, brain injuries, spinal cord injuries, Parkinson’s disease, and multiple sclerosis. SRC is an outpatient facility that treats these conditions, especially stroke and brain injuries, as well as a variety of pediatric neurological problems (developmental delay, autism, learning disabilities, etc.). This issue of the Rhode Island Medical Journal focuses on neurorehabilitation. In the first article, Marilyn Serra (a speech language pathologist by training and the president of SRC) and I discuss the pathophysiology of and rehabilitation after sports concussions. The second article is by Amanda Dragga, a speech language pathologist at SNERC, who describes treatments for speech, swallow, and cognitive problems after a stroke. As a clinician and faculty member of the Orthopedic Surgery department at Brown University, I often collaborate with the orthopedic residents. Therefore, I’m pleased that some of these surgeons-in-training have contributed articles on orthopedic complications during neurorehabilitation. For instance, orthopedic surgeons can help with procedures such as tendon lengthening for spasticity when conservative measures are not working. In some cases, heterotopic ossification after a brain or spinal cord injury may require surgical intervention, so collaboration with orthopedic surgeons is important in neurorehabilitation. Back pain and radiculopathy are common conditions in the outpatient setting, but on occasion there can be concomitant conditions such as ruptured hamstring tendons, as described in a case report. During the difficult process of neurorehabilitation, I admire my patients, their families, and their clinical team as they contend with challenging disabilities. Inpatient facilities such as the Southern New England Rehabilitation Center and outpatient centers such as Sargent Rehabilitation Center offer a therapeutic haven for people with disabilities who wish to improve their independence and quality of life.

http://rimed.org/rimedicaljournal/2015/12/2015-12-15-neuro-mukand.pdf

Jon A. Mukand

Papers

A pilot study of pain management during rehabilitation for hip and knee arthroplasty.

Human immunodeficiency virus infection and diffuse polyneuropathy. Implications for rehabilitation medicine.

Low back pain, radiculopathy, and bilateral proximal hamstring ruptures: a case report.

Delayed diagnosis of concomitant rotator cuff tear and brachial plexopathy in a patient with traumatic brain injury: a case report.

Neurorehabilitation: achieving recovery after neural injuries.