Solaiman Shokur

École Polytechnique Fédérale de Lausanne | EPFL · neurorehabilitation

Balance impairment is a common symptom of Parkinson’s disease (PD), suggesting the reclassification of the PD to a tetrad: rest tremor, rigidity, bradykinesia, and balance impairment. Falling is the most evident symptom of inadequate balance. Falls are expected to be twice as likely in individuals with PD compared to age-matched controls, and PD ha...

Human-machine interfaces (HMIs) can be used to decode a user's motor intention to control an external device. People that suffer from motor disabilities, such as spinal cord injury, can benefit from the uses of these interfaces. While many solutions can be found in this direction, there is still room for improvement both from a decoding, hardware,...

The use of hands for gathering rich sensory information is essential for proper interaction with the environment; therefore, the restoration of sensation is critical for reestablishing the sense of embodiment in hand amputees. Here, we show that a noninvasive wearable device can be used to provide thermal sensations on amputees' phantom hands. The...

Full-text available at: https://rdcu.be/daaqL

Introduction: This study aims to evaluate the effects of medication, and the freezing of gait (FoG) on the kinematic and kinetic parameters of gait in people with Parkinson's disease (pwPD) compared to neurologically healthy. Methods: Twenty-two people with a clinical diagnosis of idiopathic PD in ON and OFF medication (11 FoG), and 18 healthy p...

In recent years, our group and others have reported multiple cases of consistent neurological recovery in people with spinal cord injury (SCI) following a protocol that integrates locomotion training with brain machine interfaces (BMI). The primary objective of this pilot study was to compare the neurological outcomes (motor, tactile, nociception,...

Brain-body interfaces (BBIs) are neuroprostheses that can restore the connection between brain activity and body movements. They have emerged as a radical solution for restoring voluntary hand control in people with upper-limb paralysis. The BBI module decoding motor commands to actuate the limb from brain signals should provide the user with intui...

Background Joint biomechanics and spatiotemporal gait parameters change with age or disease and are used in treatment decision-making. Research question: To investigate whether kinematic predictors of spatiotemporal parameters during gait differ by age in healthy individuals. Methods: We used an open dataset with the gait data of 114 young adults (...

The emergence of robotic body augmentation provides exciting innovations that will revolutionize the fields of robotics, human–machine interaction and wearable electronics. Although augmentative devices such as extra robotic arms and fingers are informed by restorative technologies in many ways, they also introduce unique challenges for bidirection...

Background The freezing episode (FE) management during gait in Parkinson's disease is inefficient with current medications, neurosurgery, and physical interventions. Knowing the biomechanical change patients suffer preceding FE would be the ultimate goal to measure, predict, and prevent these events. Objective We performed a systematic review to s...

Neuroprosthetics is a discipline that aims at restoring lost functions to people affected by a variety of neurological disorders or neurotraumatic lesions. It combines the expertise of computer science and electrical, mechanical, and micro/nanotechnology with cellular, molecular, and systems neuroscience. Rapid breakthroughs in the field during the...

The desire for functional replacement of a missing hand is an ancient one. Historically, humans have replaced a missing limb with a prosthesis for cosmetic, vocational, or personal autonomy reasons. The hand is a powerful tool, and its loss causes severe physical and often mental debilitation. Technological advancements have allowed the development...

We recently interviewed Solaiman Shokur about the project that his team submitted to the BCI Research Award in 2019. We then edited the interview and added images that Dr. Shokur kindly shared to provide more information about the team and project. Their project showed how a BMI-based protocol could provide partial neurological improvements for per...

The emergence of robot-based body augmentation promises exciting innovations that will inform robotics, human-machine interaction, and wearable electronics. Even though augmentative devices like extra robotic arms and fingers in many ways build on restorative technologies, they introduce unique challenges for bidirectional human-machine collaborati...

Bidirectional hand neuroprostheses for amputee subjects aim to restore sensory–motor functions via the decoding of motor intentions in efferent channels and the stimulation of afferent nerves with electrical pulses conveying sensory information and closing the control loop. To optimize sensory feedback, neural stimulation should evoke both informat...

Nonhuman primates (NHPs) constitute an ideal model for the investigation of somatosensory feedback, as they can learn complex behavioral tasks and perform dexterous sensory-cued reaching and grasping movements. In addition, NHP models provide a meaningful way to functionally test neurotechnologies developed for human subjects, facilitating their tr...

Significance Sensory neuroprostheses offer the promise of restoring perceptual function to people with impaired sensation. Here, we developed a paradigm using intracortical microstimulation (ICMS) for encoding the sensation of fingertip motion against texture. Monkeys learned to interpret time-varying ICMS patterns, evoked by the interplay of their...

Spinal cord injury (SCI) impairs the flow of sensory and motor signals between the brain and the areas of the body located below the lesion level. Here, we describe a neurorehabilitation setup combining several approaches that were shown to have a positive effect in patients with SCI: gait training by means of non-invasive, surface functional elect...

Intracortical microstimulation (ICMS) of the primary somatosensory cortex (S1) can produce percepts that mimic somatic sensation and thus has potential as an approach to sensorize prosthetic limbs. However, it is not known whether ICMS could recreate active texture exploration-the ability to infer information about object texture by using one′s fin...

Exoskeletons are a perfect example of a mechatronics product. They illustrate the close integration and interdependence of mechanical design, drive train, sensors, control strategy and user interface. Recent developments of our lab will be discussed in detail. Application examples include paraplegics, amputees, muscular dystrophy patients. The moti...

Spinal cord injury (SCI) induces severe deficiencies in sensory-motor and autonomic functions and has a significant negative impact on patients’ quality of life. There is currently no systematic rehabilitation technique assuring recovery of the neurological impairments caused by a complete SCI. Here, we report significant clinical improvement in a...

ASIA score sheet for all patients at onset and at the end of the training. (PDF)

MRI of patients’ spinal cord. (A) MRI cuts of sagittal and (B) axial planes (T2 sequence) at SCI level for patients P2, P3, P4. Myelomalacia (hyperintense signal, 7mm length) is visible for patient P2 at the level of thoracic vertebra T2, and continuity of neural fibers are visible at the lesion level. For patient P3, we observed the spinal cord in...

3D MRI reconstruction. Three-dimensional reconstruction based on FIESTA sequence images for patient P4. The rendering was done with OsiriX Lite software. Published with permission of Associação Alberto Santos Dumont para Apoio à Pesquisa (AASDAP), Sao Paulo, Brazil. (MP4)

ASIA motor examination of patient P3. The motor exam is done 32 months after the onset of the training. The patient is asked to align the lower limbs, performing hip adduction and knee extension, for the left side and later for the right side. Published with permission of Associação Alberto Santos Dumont para Apoio à Pesquisa (AASDAP), Sao Paulo, B...

For each muscle, the corresponding nerve, nerve root range. The reported principal nerve is the one reported in ASIA assessment (except extensor digitorum longus which is not part of the ASIA assessment). (DOCX)

Patient’s proprioception score per movement after 28 months of training. (DOCX)

Motor examination in a suspended position for patient P1. The motor exam was done 9 and 22 months after the onset of the training. The patient is instructed to flex the right hip. Published with permission of Associação Alberto Santos Dumont para Apoio à Pesquisa (AASDAP), Sao Paulo, Brazil. (MP4)

Motor examination in a suspended position for patient P8. The motor exam was done 29 months after the training onset. The patient was instructed to move both legs alternatively backward (right and later left side) and forward (right and later left side); with 75–80% of body weight support during forward movement and 65–70% during backward movement....

WHOQOL-BREF set of questions per domain. (DOCX)

Spinal cord injuries disrupt bidirectional communication between the patient’s brain and body. Here, we demonstrate a new approach for reproducing lower limb somatosensory feedback in paraplegics by remapping missing leg/foot tactile sensations onto the skin of patients’ forearms. A portable haptic display was tested in eight patients in a setup wh...

Brain-machine interfaces (BMIs) provide a new assistive strategy aimed at restoring mobility in severely paralyzed patients. Yet, no study in animals or in human subjects has indicated that long-term BMI training could induce any type of clinical recovery. Eight chronic (3–13 years) spinal cord injury (SCI) paraplegics were subjected to long-term t...

Everyday, people use numerous high-quality commercial software packages on desktop systems. Many times, these software packages are not able to access specialized virtual reality (VR) display and input devices, which can enhance interaction and visualization. To address this limitation, we have been using the well-known OpenGL intercept concept to...

We—as humans—can learn to use tools like hammers, tennis rackets, scalpels or robotic arms. Learning curves to become proficient in using the tools can be very different. Typical questions for learning use of a new tool are the level of complexity in manipulation, i.e. learning time and the ergonomy. We ask here these questions from a cognitive neu...

Worldwide, millions of people suffer from walking impairments. Brain-machine interfaces (BMI) offer a promising alternative for restoring motor behavior in patients affected by lower limb paralysis. Here, we present a new paradigm for patients affected by a complete lesion of the lower spinal cord to learn how to operate, in a safe and reliable man...

Brain-machine interfaces (BMIs) are artificial systems that aim to restore sensation and movement to paralyzed patients. So far, BMIs have enabled only one arm to be moved at a time. Control of bimanual arm movements remains a major challenge. We have developed and tested a bimanual BMI that enables rhesus monkeys to control two avatar arms simulta...

The brain representation of the body, called the body schema, is susceptible to plasticity. For instance, subjects experiencing a rubber hand illusion develop a sense of ownership of a mannequin hand when they view it being touched while tactile stimuli are simultaneously applied to their own hand. Here, the cortical basis of such an embodiment was...

Brain-machine interfaces use neuronal activity recorded from the brain to establish direct communication with external actuators, such as prosthetic arms. It is hoped that brain-machine interfaces can be used to restore the normal sensorimotor functions of the limbs, but so far they have lacked tactile sensation. Here we report the operation of a b...

This paper proposes a novel experimental environment to evaluate multimodal feedback strategies for augmented navigation of the visually impaired. The environment consists of virtual obstacles and walls, an optical tracking system and a simple device with audio and vibrotactile feedback that interacts with the virtual environment, and presents many...

This paper proposes a novel experimental environment to evaluate multimodal feedback strategies for augmented navigation of the visually impaired. The environment consists of virtual obstacles and walls, an optical tracking system and a simple device with audio and vibrotactile feedback that interacts with the virtual environment, and presents many...

Designed and evolved self-replicating structures in cellular automata have been extensively studied in the past as models of Artificial Life. However, CAs, unlike their biological counterpart, are very brittle: any faulty cell usually leads to the complete destruction of any emerging structures, let alone self-replicating structures. A way to desig...

Designed and evolved self-replicating structures in cellular automata have been extensively studied in the past as models of Artificial Life. However, CAs, unlike their biological counterpart, are very brittle: any faulty cell usually leads to the complete destruction of any emerging structures, let alone self-replicating structures. A way to desig...

In this article we described the attempt to build a robot able to locate and follow an human target moving in a domestic environment. After a brief review of the state of the art in relative location technologies, we described our approach that aims to develop robots provided with simple and robust relative location technologies that do not require...

We are interested in developing and building an experimental system for controlling a quadruped robot with a brain-derived signal of a rat. We recorded large ensembles of neurones in left M1 and right M1 and S1 using chronically implanted multi-electrodes arrays (up to 96 electrodes) in rats. The interpretation of such signals has proceeded to an a...

The possibility to use information from cortical neurons to drive neuroprosthetic devices is an area that has recently garnered a lot of attention within neuroscience. Most of this research has been directed towards restoring upper limb motility. In this study, we have started to assess the possibility of using cortical neurons to drive a lower lim...

Abstract: Recent advances in brain-machine interfaces (BMIs) have demonstrated the possibility of motor neuroprosthetics directly controlled by brain activity. Ideally neuroprosthetic limbs should be integrated in the body schema of the subject. To explore the ways to enhance such incorporation, we recorded modulations of neuronal ensemble activity...