301
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Moraud EM, von Zitzewitz J, Miehlbradt J, Wurth S, Formento E, DiGiovanna J, Capogrosso M, Courtine G, Micera S. Closed-loop control of trunk posture improves locomotion through the regulation of leg proprioceptive feedback after spinal cord injury. Sci Rep 2018; 8:76. [PMID: 29311614 PMCID: PMC5758718 DOI: 10.1038/s41598-017-18293-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 12/05/2017] [Indexed: 01/09/2023] Open
Abstract
After spinal cord injury (SCI), sensory feedback circuits critically contribute to leg motor execution. Compelled by the importance to engage these circuits during gait rehabilitation, assistive robotics and training protocols have primarily focused on guiding leg movements to reinforce sensory feedback. Despite the importance of trunk postural dynamics on gait and balance, trunk assistance has comparatively received little attention. Typically, trunk movements are either constrained within bodyweight support systems, or manually adjusted by therapists. Here, we show that real-time control of trunk posture re-established dynamic balance amongst bilateral proprioceptive feedback circuits, and thereby restored left-right symmetry, loading and stepping consistency in rats with severe SCI. We developed a robotic system that adjusts mediolateral trunk posture during locomotion. This system uncovered robust relationships between trunk orientation and the modulation of bilateral leg kinematics and muscle activity. Computer simulations suggested that these modulations emerged from corrections in the balance between flexor- and extensor-related proprioceptive feedback. We leveraged this knowledge to engineer control policies that regulate trunk orientation and postural sway in real-time. This dynamical postural interface immediately improved stepping quality in all rats regardless of broad differences in deficits. These results emphasize the importance of trunk regulation to optimize performance during rehabilitation.
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Affiliation(s)
- Eduardo Martin Moraud
- Bertarelli Foundation Chair in Translational Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, Swiss Federal Institute of Technology (EPFL), CH-1202, Geneva, Switzerland.
| | - Joachim von Zitzewitz
- International Paraplegic Foundation Chair in Spinal Cord Repair, Center for Neuroprosthetics and Brain Mind Institute, Swiss Federal Institute of Technology (EPFL), CH-1202, Geneva, Switzerland
| | - Jenifer Miehlbradt
- Bertarelli Foundation Chair in Translational Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, Swiss Federal Institute of Technology (EPFL), CH-1202, Geneva, Switzerland
| | - Sophie Wurth
- Bertarelli Foundation Chair in Translational Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, Swiss Federal Institute of Technology (EPFL), CH-1202, Geneva, Switzerland
| | - Emanuele Formento
- Bertarelli Foundation Chair in Translational Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, Swiss Federal Institute of Technology (EPFL), CH-1202, Geneva, Switzerland
| | - Jack DiGiovanna
- Bertarelli Foundation Chair in Translational Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, Swiss Federal Institute of Technology (EPFL), CH-1202, Geneva, Switzerland
| | | | - Grégoire Courtine
- International Paraplegic Foundation Chair in Spinal Cord Repair, Center for Neuroprosthetics and Brain Mind Institute, Swiss Federal Institute of Technology (EPFL), CH-1202, Geneva, Switzerland.
| | - Silvestro Micera
- Bertarelli Foundation Chair in Translational Neuroengineering, Center for Neuroprosthetics and Institute of Bioengineering, Swiss Federal Institute of Technology (EPFL), CH-1202, Geneva, Switzerland.,The BioRobotics Institute, Scuola Superiore Sant'Anna, 56127, Pisa, Italy
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302
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303
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Donoghue JP. Brain–Computer Interfaces. Neuromodulation 2018. [DOI: 10.1016/b978-0-12-805353-9.00025-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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304
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Rapid fabrication of microneedles using magnetorheological drawing lithography. Acta Biomater 2018; 65:283-291. [PMID: 29107057 DOI: 10.1016/j.actbio.2017.10.030] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 09/22/2017] [Accepted: 10/17/2017] [Indexed: 12/12/2022]
Abstract
Microneedles are micron-sized needles that are widely applied in biomedical fields owing to their painless, minimally invasive, and convenient operation. However, most microneedle fabrication approaches are costly, time consuming, involve multiple steps, and require expensive equipment. In this study, we present a novel magnetorheological drawing lithography (MRDL) method to efficiently fabricate microneedle, bio-inspired microneedle, and molding-free microneedle array. With the assistance of an external magnetic field, the 3D structure of a microneedle can be directly drawn from a droplet of curable magnetorheological fluid. The formation process of a microneedle consists of two key stages, elasto-capillary self-thinning and magneto-capillary self-shrinking, which greatly affect the microneedle height and tip radius. Penetration and fracture tests demonstrated that the microneedle had sufficient strength and toughness for skin penetration. Microneedle arrays and a bio-inspired microneedle were also fabricated, which further demonstrated the versatility and flexibility of the MRDL method. STATEMENT OF SIGNIFICANCE Microneedles have been widely applied in biomedical fields owing to their painless, minimally invasive, and convenient operation. However, most microneedle fabrication approaches are costly, time consuming, involve multiple steps, and require expensive equipment. Furthermore, most researchers have focused on the biomedical applications of microneedles but have given little attention to the optimization of the fabrication process. This research presents a novel magnetorheological drawing lithography (MRDL) method to fabricate microneedle, bio-inspired microneedle, and molding-free microneedle array. In this proposed technique, a droplet of curable magnetorheological fluid (CMRF) is drawn directly from almost any substrate to produce a 3D microneedle under an external magnetic field. This method not only inherits the advantages of thermal drawing approach without the need for a mask and light irradiation but also eliminates the requirement for drawing temperature adjustment. The MRDL method is extremely simple and can even produce the complex and multiscale structure of bio-inspired microneedle.
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305
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Knudsen EB, Moxon KA. Restoration of Hindlimb Movements after Complete Spinal Cord Injury Using Brain-Controlled Functional Electrical Stimulation. Front Neurosci 2017; 11:715. [PMID: 29311792 PMCID: PMC5742140 DOI: 10.3389/fnins.2017.00715] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 12/07/2017] [Indexed: 11/20/2022] Open
Abstract
Single neuron and local field potential signals recorded in the primary motor cortex have been repeatedly demonstrated as viable control signals for multi-degree-of-freedom actuators. Although the primary source of these signals has been fore/upper limb motor regions, recent evidence suggests that neural adaptation underlying neuroprosthetic control is generalizable across cortex, including hindlimb sensorimotor cortex. Here, adult rats underwent a longitudinal study that included a hindlimb pedal press task in response to cues for specific durations, followed by brain machine interface (BMI) tasks in healthy rats, after rats received a complete spinal transection and after the BMI signal controls epidural stimulation (BMI-FES). Over the course of the transition from learned behavior to BMI task, fewer neurons were responsive after the cue, the proportion of neurons selective for press duration increased and these neurons carried more information. After a complete, mid-thoracic spinal lesion that completely severed both ascending and descending connections to the lower limbs, there was a reduction in task-responsive neurons followed by a reacquisition of task selectivity in recorded populations. This occurred due to a change in pattern of neuronal responses not simple changes in firing rate. Finally, during BMI-FES, additional information about the intended press duration was produced. This information was not dependent on the stimulation, which was the same for short and long duration presses during the early phase of stimulation, but instead was likely due to sensory feedback to sensorimotor cortex in response to movement along the trunk during the restored pedal press. This post-cue signal could be used as an error signal in a continuous decoder providing information about the position of the limb to optimally control a neuroprosthetic device.
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Affiliation(s)
- Eric B Knudsen
- School of Biomedical Engineering, Science, and Health Systems, Drexel University, Philadelphia, PA, United States
| | - Karen A Moxon
- School of Biomedical Engineering, Science, and Health Systems, Drexel University, Philadelphia, PA, United States.,Department of Biomedical Engineering, University of California, Davis, Davis, CA, United States
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306
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Jack AS, Hurd C, Forero J, Nataraj A, Fenrich K, Blesch A, Fouad K. Cortical electrical stimulation in female rats with a cervical spinal cord injury to promote axonal outgrowth. J Neurosci Res 2017; 96:852-862. [DOI: 10.1002/jnr.24209] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/27/2017] [Accepted: 11/27/2017] [Indexed: 01/13/2023]
Affiliation(s)
- Andrew S. Jack
- Division of Neurosurgery, Department of Surgery, Faculty of Medicine and Dentistry; University of Alberta Hospital; Edmonton Alberta Canada
- Neuroscience and Mental Health Institute, Faculty of Medicine and Dentistry; University of Alberta; Edmonton Alberta Canada
| | - Caitlin Hurd
- Department of Physical Therapy, Faculty of Rehabilitation Medicine; University of Alberta; Edmonton Alberta Canada
| | - Juan Forero
- Department of Physical Therapy, Faculty of Rehabilitation Medicine; University of Alberta; Edmonton Alberta Canada
| | - Andrew Nataraj
- Division of Neurosurgery, Department of Surgery, Faculty of Medicine and Dentistry; University of Alberta Hospital; Edmonton Alberta Canada
- Neuroscience and Mental Health Institute, Faculty of Medicine and Dentistry; University of Alberta; Edmonton Alberta Canada
| | - Keith Fenrich
- Department of Physical Therapy, Faculty of Rehabilitation Medicine; University of Alberta; Edmonton Alberta Canada
| | - Armin Blesch
- Stark Neuroscience Research Institute; Indiana University; Indianapolis Indiana
| | - Karim Fouad
- Neuroscience and Mental Health Institute, Faculty of Medicine and Dentistry; University of Alberta; Edmonton Alberta Canada
- Department of Physical Therapy, Faculty of Rehabilitation Medicine; University of Alberta; Edmonton Alberta Canada
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307
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Höller Y, Tadzic A, Thomschewski AC, Höller P, Leis S, Tomasi SO, Hofer C, Bathke A, Nardone R, Trinka E. Factors Affecting Volume Changes of the Somatosensory Cortex in Patients with Spinal Cord Injury: To Be Considered for Future Neuroprosthetic Design. Front Neurol 2017; 8:662. [PMID: 29321758 PMCID: PMC5732216 DOI: 10.3389/fneur.2017.00662] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Accepted: 11/23/2017] [Indexed: 01/10/2023] Open
Abstract
Spinal cord injury (SCI) leads to severe chronic disability, but also to secondary adaptive changes upstream to the injury in the brain which are most likely induced due to the lack of afferent information. These neuroplastic changes are a potential target for innovative therapies such as neuroprostheses, e.g., by stimulation in order to evoke sensation or in order to suppress phantom limb pain. Diverging results on gray matter atrophy have been reported in patients with SCI. Detectability of atrophy seems to depend on the selection of the regions of interest, while whole-brain approaches are not sensitive enough. In this study, we discussed previous research approaches and analyzed differential atrophic changes in incomplete SCI using manual segmentation of the somatosensory cortex. Patients with incomplete SCI (ASIA C-D), with cervical (N = 5) and thoracic (N = 6) injury were included. Time since injury was ≤12 months in 7 patients, and 144, 152, 216, and 312 months in the other patients. Age at the injury was ≤26 years in 4 patients and ≥50 years in 7 patients. A sample of 12 healthy controls was included in the study. In contrast to all previous studies that used voxel-based morphometry, we performed manual segmentation of the somatosensory cortex in the postcentral gyrus from structural magnetic resonance images and normalized the calculated volumes against the sum of volumes of an automated whole-head segmentation. Volumes were smaller in patients than in controls (p = 0.011), and as a tendency, female patients had smaller volumes than male patients (p = 0.017, uncorrected). No effects of duration (subacute vs. chronic), level of lesion (cervical vs. thoracic), region (left vs. right S1), and age at onset (≤26 vs. ≥50 years) was found. Our results demonstrate volume loss of S1 in incomplete SCI and encourage further research with larger sample sizes on volumetric changes in the acute and chronic stage of SCI, in order to document the moderating effect of type and location of injury on neuroplastic changes. A better understanding of neuroplastic changes in the sensorimotor cortex after SCI and its interaction with sex is needed in order to develop efficient rehabilitative interventions and neuroprosthetic technologies.
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Affiliation(s)
- Yvonne Höller
- Department of Neurology, Christian Doppler Medical Centre and Centre for Cognitive Neuroscience, Paracelsus Medical University Salzburg, Salzburg, Austria
| | - Arijan Tadzic
- Department of Neurology, Christian Doppler Medical Centre and Centre for Cognitive Neuroscience, Paracelsus Medical University Salzburg, Salzburg, Austria
| | - Aljoscha C. Thomschewski
- Department of Neurology, Christian Doppler Medical Centre and Centre for Cognitive Neuroscience, Paracelsus Medical University Salzburg, Salzburg, Austria
- Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria
| | - Peter Höller
- Department of Neurology, Christian Doppler Medical Centre and Centre for Cognitive Neuroscience, Paracelsus Medical University Salzburg, Salzburg, Austria
- Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria
| | - Stefan Leis
- Department of Neurology, Christian Doppler Medical Centre and Centre for Cognitive Neuroscience, Paracelsus Medical University Salzburg, Salzburg, Austria
- Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria
| | - Santino Ottavio Tomasi
- Department of Neurosurgery, Paracelsus Medical University of Salzburg, Salzburg, Austria
| | - Christoph Hofer
- Wavelab, Department of Computer Sciences, University of Salzburg, Salzburg, Austria
| | - Arne Bathke
- Department of Mathematics, University of Salzburg, Salzburg, Austria
| | - Raffaele Nardone
- Department of Neurology, Christian Doppler Medical Centre and Centre for Cognitive Neuroscience, Paracelsus Medical University Salzburg, Salzburg, Austria
- Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria
- Department of Neurology, Franz Tappeiner Hospital, Merano, Italy
| | - Eugen Trinka
- Department of Neurology, Christian Doppler Medical Centre and Centre for Cognitive Neuroscience, Paracelsus Medical University Salzburg, Salzburg, Austria
- Spinal Cord Injury and Tissue Regeneration Center, Paracelsus Medical University, Salzburg, Austria
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308
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Mazurek KA, Schieber MH. Injecting Instructions into Premotor Cortex. Neuron 2017; 96:1282-1289.e4. [PMID: 29224724 DOI: 10.1016/j.neuron.2017.11.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Revised: 07/10/2017] [Accepted: 11/02/2017] [Indexed: 10/18/2022]
Abstract
The premotor cortex (PM) receives inputs from parietal cortical areas representing processed visuospatial information, translates that information into programs for particular movements, and communicates those programs to the primary motor cortex (M1) for execution. Consistent with this general function, intracortical microstimulation (ICMS) in the PM of sufficient frequency, amplitude, and duration has been shown to evoke complex movements of the arm and hand that vary systematically depending on the locus of stimulation. Using frequencies and amplitudes too low to evoke muscle activity, however, we found that ICMS in the PM can provide instructions to perform specific reach, grasp, and manipulate movements. These instructed actions were not fixed but rather were learned through associations between the arbitrary stimulation locations and particular movements. Low-amplitude ICMS at different PM locations thus evokes distinguishable experiences that can become associated with specific movements arbitrarily, providing a novel means of injecting information into the nervous system.
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Affiliation(s)
- Kevin A Mazurek
- Department of Neurology, University of Rochester, Rochester, NY, USA; Del Monte Institute for Neuroscience, University of Rochester, Rochester, NY, USA.
| | - Marc H Schieber
- Department of Neurology, University of Rochester, Rochester, NY, USA; Department of Neuroscience, University of Rochester, Rochester, NY, USA; Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA; Del Monte Institute for Neuroscience, University of Rochester, Rochester, NY, USA.
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309
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Central nervous system microstimulation: Towards selective micro-neuromodulation. CURRENT OPINION IN BIOMEDICAL ENGINEERING 2017. [DOI: 10.1016/j.cobme.2017.09.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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310
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Changes in cortical network connectivity with long-term brain-machine interface exposure after chronic amputation. Nat Commun 2017; 8:1796. [PMID: 29180616 PMCID: PMC5703974 DOI: 10.1038/s41467-017-01909-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 10/24/2017] [Indexed: 11/23/2022] Open
Abstract
Studies on neural plasticity associated with brain–machine interface (BMI) exposure have primarily documented changes in single neuron activity, and largely in intact subjects. Here, we demonstrate significant changes in ensemble-level functional connectivity among primary motor cortical (MI) neurons of chronically amputated monkeys exposed to control a multiple-degree-of-freedom robot arm. A multi-electrode array was implanted in M1 contralateral or ipsilateral to the amputation in three animals. Two clusters of stably recorded neurons were arbitrarily assigned to control reach and grasp movements, respectively. With exposure, network density increased in a nearly monotonic fashion in the contralateral monkeys, whereas the ipsilateral monkey pruned the existing network before re-forming a denser connectivity. Excitatory connections among neurons within a cluster were denser, whereas inhibitory connections were denser among neurons across the two clusters. These results indicate that cortical network connectivity can be modified with BMI learning, even among neurons that have been chronically de-efferented and de-afferented due to amputation. Previous studies have shown short-term plasticity in single neurons or local field potentials during brain-machine interface (BMI) training. Here the authors report long-term changes in functional connectivity of motor cortex neuronal ensemble activity as chronically amputated monkeys learn to operate a BMI.
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311
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Phillips AA, Squair JW, Sayenko DG, Edgerton VR, Gerasimenko Y, Krassioukov AV. An Autonomic Neuroprosthesis: Noninvasive Electrical Spinal Cord Stimulation Restores Autonomic Cardiovascular Function in Individuals with Spinal Cord Injury. J Neurotrauma 2017; 35:446-451. [PMID: 28967294 PMCID: PMC5793952 DOI: 10.1089/neu.2017.5082] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Despite autonomic dysfunction after spinal cord injury (SCI) being the major cause of death and a top health priority, the clinical management options for these conditions are limited to drugs with delayed onset and nonpharmacological interventions with equivocal effectiveness. We tested the capacity of electrical stimulation, applied transcutaneously over the spinal cord, to manage autonomic dysfunction in the form of orthostatic hypotension after SCI. We assessed beat-by-beat blood pressure (BP), stroke volume, and cardiac contractility (dP/dt; Finometer), as well as cerebral blood flow (transcranial Doppler) in 5 individuals with motor-complete SCI (4 cervical, 1 thoracic) during an orthostatic challenge with and without transcutaneous electrical stimulation applied at the TVII level. During the orthostatic challenge, all individuals experienced hypotension characterized by a 37 ± 4 mm Hg decrease in systolic BP, a 52 ± 10% reduction in cardiac contractility, and a 23 ± 6% reduction in cerebral blood flow (all p < 0.05), along with severe self-reported symptoms. Electrical stimulation completely normalized BP, cardiac contractility, cerebral blood flow, and abrogated all symptoms. Noninvasive transcutaneous electrical spinal cord stimulation may be a viable therapy for restoring autonomic cardiovascular control after SCI.
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Affiliation(s)
- Aaron A Phillips
- 1 ICORD-BSCC, University of British Columbia , Vancouver, British Columbia, Canada
| | - Jordan W Squair
- 1 ICORD-BSCC, University of British Columbia , Vancouver, British Columbia, Canada
| | - Dimitry G Sayenko
- 2 Department of Integrative Biology and Physiology, University of California , Los Angeles, Los Angeles, California
| | - V Reggie Edgerton
- 2 Department of Integrative Biology and Physiology, University of California , Los Angeles, Los Angeles, California.,3 Neurobiology, University of California , Los Angeles, Los Angeles, California.,4 Department of Neurosurgery, David Geffen School of Medicine, University of California , Los Angeles, Los Angeles, California.,5 Brain Research Institute, University of California , Los Angeles, Los Angeles, California
| | - Yury Gerasimenko
- 2 Department of Integrative Biology and Physiology, University of California , Los Angeles, Los Angeles, California.,6 Pavlov Institute of Physiology , Saint-Petersburg, Russia
| | - Andrei V Krassioukov
- 1 ICORD-BSCC, University of British Columbia , Vancouver, British Columbia, Canada
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312
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Barriga-Rivera A, Tatarinoff V, Lovell NH, Morley JW, Suaning GJ. Long-term anesthetic protocol in rats: feasibility in electrophysiology studies in visual prosthesis. Vet Ophthalmol 2017; 21:290-297. [PMID: 29148158 DOI: 10.1111/vop.12507] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Electrical stimulation of excitable cells provides therapeutic benefits for a variety of medical conditions, including restoration of partial vision to those blinded via some types of retinal degeneration. To improve visual percepts elicited by the current technology, researchers are conducting acute electrophysiology experiments, mainly in cats. However, the rat can provide a model of a range of retinal diseases and possesses a sufficiently large eye to be used in this field. This article presents a long-term anesthetic protocol to enable electrophysiology experiments to further the development of visual prostheses. Six Long-Evans rats (aged between 14 and 16 weeks) were included in this study. Surgical anesthesia was maintained for more than 15 h by combining constant intravenous infusion of ketamine (24.0-34.5 mg/kg/h), xylazine (0.9-1.2 mg/kg/h), and inhaled isoflurane in oxygen (<0.5%). Overall heart rate, respiratory rate, and body temperature remained between 187-233 beats/min, 45-58 breaths/min, and 36-38 °C, respectively. Neural responses to 200-ms light pulses were recorded from the superior colliculus using a 32-channel neural probe at the beginning and before termination of the experiment. Robust responses were recorded from distinct functional types of retinal pathways. In addition, a platinum electrode was implanted in the retrobulbar space. The retina was electrically stimulated, and the activation threshold was determined to be 5.24 ± 0.24 μC/cm2 . This protocol may be used not only in the field of visual prosthesis research, but in other research areas requiring longer term acute experiments.
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Affiliation(s)
- Alejandro Barriga-Rivera
- Graduate School of Biomedical Engineering, UNSW, Sydney, NSW, 2052, Australia.,Division of Neuroscience, University Pablo de Olavide, Sevilla, 41013, Spain
| | - Veronica Tatarinoff
- Sydney Imaging Core Research Facility, The University of Sydney, NSW, 2006, Australia
| | - Nigel H Lovell
- Graduate School of Biomedical Engineering, UNSW, Sydney, NSW, 2052, Australia
| | - John W Morley
- School of Medicine, The University of Western Sydney, Sydney, NSW, Australia.,School of Medical Science, UNSW, Sydney, NSW, 2052, Australia
| | - Gregg J Suaning
- Sydney Medical School, The University of Sydney, NSW, 2006, Australia.,Faculty of Engineering and Information Technologies, The University of Sydney, NSW, 2006, Australia
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313
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Lacquaniti F, Ivanenko YP, Sylos-Labini F, La Scaleia V, La Scaleia B, Willems PA, Zago M. Human Locomotion in Hypogravity: From Basic Research to Clinical Applications. Front Physiol 2017; 8:893. [PMID: 29163225 PMCID: PMC5682019 DOI: 10.3389/fphys.2017.00893] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 10/24/2017] [Indexed: 01/07/2023] Open
Abstract
We have considerable knowledge about the mechanisms underlying compensation of Earth gravity during locomotion, a knowledge obtained from physiological, biomechanical, modeling, developmental, comparative, and paleoanthropological studies. By contrast, we know much less about locomotion and movement in general under sustained hypogravity. This lack of information poses a serious problem for human space exploration. In a near future humans will walk again on the Moon and for the first time on Mars. It would be important to predict how they will move around, since we know that locomotion and mobility in general may be jeopardized in hypogravity, especially when landing after a prolonged weightlessness of the space flight. The combination of muscle weakness, of wearing a cumbersome spacesuit, and of maladaptive patterns of locomotion in hypogravity significantly increase the risk of falls and injuries. Much of what we currently know about locomotion in hypogravity derives from the video archives of the Apollo missions on the Moon, the experiments performed with parabolic flight or with body weight support on Earth, and the theoretical models. These are the topics of our review, along with the issue of the application of simulated hypogravity in rehabilitation to help patients with deambulation problems. We consider several issues that are common to the field of space science and clinical rehabilitation: the general principles governing locomotion in hypogravity, the methods used to reduce gravity effects on locomotion, the extent to which the resulting behavior is comparable across different methods, the important non-linearities of several locomotor parameters as a function of the gravity reduction, the need to use multiple methods to obtain reliable results, and the need to tailor the methods individually based on the physiology and medical history of each person.
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Affiliation(s)
- Francesco Lacquaniti
- Department of Systems Medicine, University of Rome Tor Vergata, Rome, Italy
- Center of Space BioMedicine, University of Rome Tor Vergata, Rome, Italy
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Yury P. Ivanenko
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Francesca Sylos-Labini
- Center of Space BioMedicine, University of Rome Tor Vergata, Rome, Italy
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Valentina La Scaleia
- Center of Space BioMedicine, University of Rome Tor Vergata, Rome, Italy
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Barbara La Scaleia
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
| | - Patrick A. Willems
- Laboratory of Biomechanics and Physiology of Locomotion, Institute of NeuroScience, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Myrka Zago
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy
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314
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Raffin E, Hummel FC. Restoring Motor Functions After Stroke: Multiple Approaches and Opportunities. Neuroscientist 2017; 24:400-416. [DOI: 10.1177/1073858417737486] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
More than 1.5 million people suffer a stroke in Europe per year and more than 70% of stroke survivors experience limited functional recovery of their upper limb, resulting in diminished quality of life. Therefore, interventions to address upper-limb impairment are a priority for stroke survivors and clinicians. While a significant body of evidence supports the use of conventional treatments, such as intensive motor training or constraint-induced movement therapy, the limited and heterogeneous improvements they allow are, for most patients, usually not sufficient to return to full autonomy. Various innovative neurorehabilitation strategies are emerging in order to enhance beneficial plasticity and improve motor recovery. Among them, robotic technologies, brain-computer interfaces, or noninvasive brain stimulation (NIBS) are showing encouraging results. These innovative interventions, such as NIBS, will only provide maximized effects, if the field moves away from the “one-fits all” approach toward a “patient-tailored” approach. After summarizing the most commonly used rehabilitation approaches, we will focus on NIBS and highlight the factors that limit its widespread use in clinical settings. Subsequently, we will propose potential biomarkers that might help to stratify stroke patients in order to identify the individualized optimal therapy. We will discuss future methodological developments, which could open new avenues for poststroke rehabilitation, toward more patient-tailored precision medicine approaches and pathophysiologically motivated strategies.
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Affiliation(s)
- Estelle Raffin
- Defitech Chair of Clinical Neuroengineering, Center for Neuroprosthetics (CNP) and Brain Mind Institute (BMI), Swiss Federal Institute of Technology (EPFL), Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Center for Neuroprosthetics (CNP) and Brain Mind Institute (BMI), Swiss Federal Institute of Technology (EPFL Valais), Clinique Romande de Réadaptation, Sion, Switzerland
| | - Friedhelm C. Hummel
- Defitech Chair of Clinical Neuroengineering, Center for Neuroprosthetics (CNP) and Brain Mind Institute (BMI), Swiss Federal Institute of Technology (EPFL), Geneva, Switzerland
- Defitech Chair of Clinical Neuroengineering, Center for Neuroprosthetics (CNP) and Brain Mind Institute (BMI), Swiss Federal Institute of Technology (EPFL Valais), Clinique Romande de Réadaptation, Sion, Switzerland
- Clinical Neuroscience, University of Geneva Medical School, Geneva, Switzerland
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315
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Lee S, Peh WYX, Wang J, Yang F, Ho JS, Thakor NV, Yen S, Lee C. Toward Bioelectronic Medicine-Neuromodulation of Small Peripheral Nerves Using Flexible Neural Clip. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2017; 4:1700149. [PMID: 29201608 PMCID: PMC5700646 DOI: 10.1002/advs.201700149] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2017] [Revised: 04/30/2017] [Indexed: 05/24/2023]
Abstract
Neural modulation technology and the capability to affect organ function have spawned the new field of bioelectronic medicine. Therapeutic interventions depend on wireless bioelectronic neural interfaces that can conformally and easily attach to small (few hundred micrometers) nerves located deep in the body without neural damage. Besides size, factors like flexibility and compliance to attach and adapt to visceral nerves associated moving organs are of paramount importance and have not been previously addressed. This study proposes a novel flexible neural clip (FNC) that can be used to interface with a variety of different peripheral nerves. To illustrate the flexibility of the design, this study stimulates the pelvic nerve, the vagus nerve, and branches of the sciatic nerve and evaluates the feasibility of the design in modulating the function of each of these nerves. It is found that this FNC allows fine-tuning of physiological processes such as micturition, heart rate, and muscle contractions. Furthermore, this study also tests the ability of wirelessly powered FNC to enable remote modulation of visceral pelvic nerves located deep in the body. These results show that the FNC can be used with a range of different nerves, providing one of the critical pieces in the field of bioelectronics medicines.
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Affiliation(s)
- Sanghoon Lee
- Department of Electrical and Computer EngineeringNational University of Singapore4 Engineering Drive 3Singapore117583Singapore
- Singapore Institute for Neurotechnology (SINAPSE)National University of Singapore28 Medical Drive, #05‐CORSingapore117456Singapore
- Center for Intelligent Sensors and MEMSNational University of Singapore4 Engineering Drive 3Singapore117576Singapore
- NUS Suzhou Research Institute (NUSRI)Industrial ParkSuzhou215123P. R. China
| | - Wendy Yen Xian Peh
- Singapore Institute for Neurotechnology (SINAPSE)National University of Singapore28 Medical Drive, #05‐CORSingapore117456Singapore
| | - Jiahui Wang
- Department of Electrical and Computer EngineeringNational University of Singapore4 Engineering Drive 3Singapore117583Singapore
- Singapore Institute for Neurotechnology (SINAPSE)National University of Singapore28 Medical Drive, #05‐CORSingapore117456Singapore
- Center for Intelligent Sensors and MEMSNational University of Singapore4 Engineering Drive 3Singapore117576Singapore
- NUS Suzhou Research Institute (NUSRI)Industrial ParkSuzhou215123P. R. China
| | - Fengyuan Yang
- Department of Electrical and Computer EngineeringNational University of Singapore4 Engineering Drive 3Singapore117583Singapore
- Singapore Institute for Neurotechnology (SINAPSE)National University of Singapore28 Medical Drive, #05‐CORSingapore117456Singapore
| | - John S. Ho
- Department of Electrical and Computer EngineeringNational University of Singapore4 Engineering Drive 3Singapore117583Singapore
- Singapore Institute for Neurotechnology (SINAPSE)National University of Singapore28 Medical Drive, #05‐CORSingapore117456Singapore
| | - Nitish V. Thakor
- Department of Electrical and Computer EngineeringNational University of Singapore4 Engineering Drive 3Singapore117583Singapore
- Singapore Institute for Neurotechnology (SINAPSE)National University of Singapore28 Medical Drive, #05‐CORSingapore117456Singapore
- Graduate School for Integrative Science and EngineeringNational University of SingaporeSingapore117456Singapore
- Department of Biomedical EngineeringSchool of MedicineJohns Hopkins UniversityBaltimoreMD21205USA
| | - Shih‐Cheng Yen
- Department of Electrical and Computer EngineeringNational University of Singapore4 Engineering Drive 3Singapore117583Singapore
- Singapore Institute for Neurotechnology (SINAPSE)National University of Singapore28 Medical Drive, #05‐CORSingapore117456Singapore
| | - Chengkuo Lee
- Department of Electrical and Computer EngineeringNational University of Singapore4 Engineering Drive 3Singapore117583Singapore
- Singapore Institute for Neurotechnology (SINAPSE)National University of Singapore28 Medical Drive, #05‐CORSingapore117456Singapore
- Center for Intelligent Sensors and MEMSNational University of Singapore4 Engineering Drive 3Singapore117576Singapore
- NUS Suzhou Research Institute (NUSRI)Industrial ParkSuzhou215123P. R. China
- Graduate School for Integrative Science and EngineeringNational University of SingaporeSingapore117456Singapore
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316
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Kerschensteiner M. Neuroplasticity and its relevance for multiple sclerosis. Neurodegener Dis Manag 2017; 7:31-33. [DOI: 10.2217/nmt-2017-0039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Affiliation(s)
- Martin Kerschensteiner
- Institute of Clinical Neuroimmunology, Biomedical Center & Hospital of the Ludwig-Maximilians University, Munich, Germany
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317
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Ghafoor U, Kim S, Hong KS. Selectivity and Longevity of Peripheral-Nerve and Machine Interfaces: A Review. Front Neurorobot 2017; 11:59. [PMID: 29163122 PMCID: PMC5671609 DOI: 10.3389/fnbot.2017.00059] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2017] [Accepted: 10/17/2017] [Indexed: 11/22/2022] Open
Abstract
For those individuals with upper-extremity amputation, a daily normal living activity is no longer possible or it requires additional effort and time. With the aim of restoring their sensory and motor functions, theoretical and technological investigations have been carried out in the field of neuroprosthetic systems. For transmission of sensory feedback, several interfacing modalities including indirect (non-invasive), direct-to-peripheral-nerve (invasive), and cortical stimulation have been applied. Peripheral nerve interfaces demonstrate an edge over the cortical interfaces due to the sensitivity in attaining cortical brain signals. The peripheral nerve interfaces are highly dependent on interface designs and are required to be biocompatible with the nerves to achieve prolonged stability and longevity. Another criterion is the selection of nerves that allows minimal invasiveness and damages as well as high selectivity for a large number of nerve fascicles. In this paper, we review the nerve-machine interface modalities noted above with more focus on peripheral nerve interfaces, which are responsible for provision of sensory feedback. The invasive interfaces for recording and stimulation of electro-neurographic signals include intra-fascicular, regenerative-type interfaces that provide multiple contact channels to a group of axons inside the nerve and the extra-neural-cuff-type interfaces that enable interaction with many axons around the periphery of the nerve. Section Current Prosthetic Technology summarizes the advancements made to date in the field of neuroprosthetics toward the achievement of a bidirectional nerve-machine interface with more focus on sensory feedback. In the Discussion section, the authors propose a hybrid interface technique for achieving better selectivity and long-term stability using the available nerve interfacing techniques.
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Affiliation(s)
- Usman Ghafoor
- School of Mechanical Engineering, Pusan National University, Busan, South Korea
| | - Sohee Kim
- Department of Robotics Engineering, Daegu Gyeongbuk Institute of Science and Technology, Daegu, South Korea
| | - Keum-Shik Hong
- School of Mechanical Engineering, Pusan National University, Busan, South Korea.,Department of Cogno-Mechatronics Engineering, Pusan National University, Busan, South Korea
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318
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Sartori M, Yavuz UŞ, Farina D. In Vivo Neuromechanics: Decoding Causal Motor Neuron Behavior with Resulting Musculoskeletal Function. Sci Rep 2017; 7:13465. [PMID: 29044165 PMCID: PMC5647446 DOI: 10.1038/s41598-017-13766-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Accepted: 09/14/2017] [Indexed: 12/30/2022] Open
Abstract
Human motor function emerges from the interaction between the neuromuscular and the musculoskeletal systems. Despite the knowledge of the mechanisms underlying neural and mechanical functions, there is no relevant understanding of the neuro-mechanical interplay in the neuro-musculo-skeletal system. This currently represents the major challenge to the understanding of human movement. We address this challenge by proposing a paradigm for investigating spinal motor neuron contribution to skeletal joint mechanical function in the intact human in vivo. We employ multi-muscle spatial sampling and deconvolution of high-density fiber electrical activity to decode accurate α-motor neuron discharges across five lumbosacral segments in the human spinal cord. We use complete α-motor neuron discharge series to drive forward subject-specific models of the musculoskeletal system in open-loop with no corrective feedback. We perform validation tests where mechanical moments are estimated with no knowledge of reference data over unseen conditions. This enables accurate blinded estimation of ankle function purely from motor neuron information. Remarkably, this enables observing causal associations between spinal motor neuron activity and joint moment control. We provide a new class of neural data-driven musculoskeletal modeling formulations for bridging between movement neural and mechanical levels in vivo with implications for understanding motor physiology, pathology, and recovery.
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Affiliation(s)
- Massimo Sartori
- Institute of Biomedical Technology and Technical Medicine, Department of Biomechanical Engineering, University of Twente, Enschede, The Netherlands
| | - Utku Ş Yavuz
- Pain Medicine, Department of Anaesthesiology, University Medical Center Göttingen, Georg-August University, Göttingen, Germany
| | - Dario Farina
- Department of Bioengineering, Imperial College London, London, United Kingdom.
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319
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320
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Brandman DM, Cash SS, Hochberg LR. Review: Human Intracortical Recording and Neural Decoding for Brain-Computer Interfaces. IEEE Trans Neural Syst Rehabil Eng 2017; 25:1687-1696. [PMID: 28278476 PMCID: PMC5815832 DOI: 10.1109/tnsre.2017.2677443] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Brain-computer interfaces (BCIs) use neural information recorded from the brain for the voluntary control of external devices. The development of BCI systems has largely focused on improving functional independence for individuals with severe motor impairments, including providing tools for communication and mobility. In this review, we describe recent advances in intracortical BCI technology and provide potential directions for further research.
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321
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Digital implementation of Hodgkin–Huxley neuron model for neurological diseases studies. ARTIFICIAL LIFE AND ROBOTICS 2017. [DOI: 10.1007/s10015-017-0397-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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322
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The brain during free movement - What can we learn from the animal model. Brain Res 2017; 1716:3-15. [PMID: 28893579 DOI: 10.1016/j.brainres.2017.09.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 08/11/2017] [Accepted: 09/04/2017] [Indexed: 11/21/2022]
Abstract
Animals, just like humans, can freely move. They do so for various important reasons, such as finding food and escaping predators. Observing these behaviors can inform us about the underlying cognitive processes. In addition, while humans can convey complicated information easily through speaking, animals need to move their bodies to communicate. This has prompted many creative solutions by animal neuroscientists to enable studying the brain during movement. In this review, we first summarize how animal researchers record from the brain while an animal is moving, by describing the most common neural recording techniques in animals and how they were adapted to record during movement. We further discuss the challenge of controlling or monitoring sensory input during free movement. However, not only is free movement a necessity to reflect the outcome of certain internal cognitive processes in animals, it is also a fascinating field of research since certain crucial behavioral patterns can only be observed and studied during free movement. Therefore, in a second part of the review, we focus on some key findings in animal research that specifically address the interaction between free movement and brain activity. First, focusing on walking as a fundamental form of free movement, we discuss how important such intentional movements are for understanding processes as diverse as spatial navigation, active sensing, and complex motor planning. Second, we propose the idea of regarding free movement as the expression of a behavioral state. This view can help to understand the general influence of movement on brain function. Together, the technological advancements towards recording from the brain during movement, and the scientific questions asked about the brain engaged in movement, make animal research highly valuable to research into the human "moving brain".
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323
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Mishra AM, Pal A, Gupta D, Carmel JB. Paired motor cortex and cervical epidural electrical stimulation timed to converge in the spinal cord promotes lasting increases in motor responses. J Physiol 2017; 595:6953-6968. [PMID: 28752624 PMCID: PMC5685837 DOI: 10.1113/jp274663] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2017] [Accepted: 07/13/2017] [Indexed: 12/04/2022] Open
Abstract
Key points Pairing motor cortex stimulation and spinal cord epidural stimulation produced large augmentation in motor cortex evoked potentials if they were timed to converge in the spinal cord. The modulation of cortical evoked potentials by spinal cord stimulation was largest when the spinal electrodes were placed over the dorsal root entry zone. Repeated pairing of motor cortex and spinal cord stimulation caused lasting increases in evoked potentials from both sites, but only if the time between the stimuli was optimal. Both immediate and lasting effects of paired stimulation are likely mediated by convergence of descending motor circuits and large diameter afferents onto common interneurons in the cervical spinal cord.
Abstract Convergent activity in neural circuits can generate changes at their intersection. The rules of paired electrical stimulation are best understood for protocols that stimulate input circuits and their targets. We took a different approach by targeting the interaction of descending motor pathways and large diameter afferents in the spinal cord. We hypothesized that pairing stimulation of motor cortex and cervical spinal cord would strengthen motor responses through their convergence. We placed epidural electrodes over motor cortex and the dorsal cervical spinal cord in rats; motor evoked potentials (MEPs) were measured from biceps. MEPs evoked from motor cortex were robustly augmented with spinal epidural stimulation delivered at an intensity below the threshold for provoking an MEP. Augmentation was critically dependent on the timing and position of spinal stimulation. When the spinal stimulation was timed to coincide with the descending volley from motor cortex stimulation, MEPs were more than doubled. We then tested the effect of repeated pairing of motor cortex and spinal stimulation. Repetitive pairing caused strong augmentation of cortical MEPs and spinal excitability that lasted up to an hour after just 5 min of pairing. Additional physiology experiments support the hypothesis that paired stimulation is mediated by convergence of descending motor circuits and large diameter afferents in the spinal cord. The large effect size of this protocol and the conservation of the circuits being manipulated between rats and humans makes it worth pursuing for recovery of sensorimotor function after injury to the central nervous system. Pairing motor cortex stimulation and spinal cord epidural stimulation produced large augmentation in motor cortex evoked potentials if they were timed to converge in the spinal cord. The modulation of cortical evoked potentials by spinal cord stimulation was largest when the spinal electrodes were placed over the dorsal root entry zone. Repeated pairing of motor cortex and spinal cord stimulation caused lasting increases in evoked potentials from both sites, but only if the time between the stimuli was optimal. Both immediate and lasting effects of paired stimulation are likely mediated by convergence of descending motor circuits and large diameter afferents onto common interneurons in the cervical spinal cord.
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Affiliation(s)
- Asht M Mishra
- Burke-Cornell Medical Research Institute, 785 Mamaroneck Avenue, White Plains, New York, 10605, USA
| | - Ajay Pal
- Burke-Cornell Medical Research Institute, 785 Mamaroneck Avenue, White Plains, New York, 10605, USA
| | - Disha Gupta
- Burke-Cornell Medical Research Institute, 785 Mamaroneck Avenue, White Plains, New York, 10605, USA.,Brain and Mind Research Institute and Departments of Neurology and Pediatrics, Weill Cornell Medical College, New York, NY, 10021, USA
| | - Jason B Carmel
- Burke-Cornell Medical Research Institute, 785 Mamaroneck Avenue, White Plains, New York, 10605, USA.,Brain and Mind Research Institute and Departments of Neurology and Pediatrics, Weill Cornell Medical College, New York, NY, 10021, USA
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324
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Arandia-Romero I, Nogueira R, Mochol G, Moreno-Bote R. What can neuronal populations tell us about cognition? Curr Opin Neurobiol 2017; 46:48-57. [PMID: 28806694 DOI: 10.1016/j.conb.2017.07.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 07/06/2017] [Accepted: 07/25/2017] [Indexed: 12/24/2022]
Abstract
Nowadays, it is possible to record the activity of hundreds of cells at the same time in behaving animals. However, these data are often treated and analyzed as if they consisted of many independently recorded neurons. How can neuronal populations be uniquely used to learn about cognition? We describe recent work that shows that populations of simultaneously recorded neurons are fundamental to understand the basis of decision-making, including processes such as ongoing deliberations and decision confidence, which generally fall outside the reach of single-cell analysis. Thus, neuronal population data allow addressing novel questions, but they also come with so far unsolved challenges.
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Affiliation(s)
- Iñigo Arandia-Romero
- Center for Brain and Cognition & Department of Information and Communications Technologies, University Pompeu Fabra, 08018 Barcelona, Spain
| | - Ramon Nogueira
- Center for Brain and Cognition & Department of Information and Communications Technologies, University Pompeu Fabra, 08018 Barcelona, Spain
| | - Gabriela Mochol
- Center for Brain and Cognition & Department of Information and Communications Technologies, University Pompeu Fabra, 08018 Barcelona, Spain
| | - Rubén Moreno-Bote
- Center for Brain and Cognition & Department of Information and Communications Technologies, University Pompeu Fabra, 08018 Barcelona, Spain; Serra Húnter Fellow Programme, 08018 Barcelona, Spain.
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325
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Kao JC, Ryu SI, Shenoy KV. Leveraging neural dynamics to extend functional lifetime of brain-machine interfaces. Sci Rep 2017; 7:7395. [PMID: 28784984 PMCID: PMC5547077 DOI: 10.1038/s41598-017-06029-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 06/07/2017] [Indexed: 01/09/2023] Open
Abstract
Intracortical brain-machine interfaces (BMIs) aim to restore lost motor function to people with neurological deficits by decoding neural activity into control signals for guiding prostheses. An important challenge facing BMIs is that, over time, the number of neural signals recorded from implanted multielectrode arrays will decline and result in a concomitant decrease of BMI performance. We sought to extend BMI lifetime by developing an algorithmic technique, implemented entirely in software, to improve performance over state-of-the-art algorithms as the number of recorded neural signals decline. Our approach augments the decoder by incorporating neural population dynamics remembered from an earlier point in the array lifetime. We demonstrate, in closed-loop experiments with two rhesus macaques, that after the loss of approximately 60% of recording electrodes, our approach outperforms state-of-the-art decoders by a factor of 3.2× and 1.7× (corresponding to a 46% and 22% recovery of maximal performance). Further, our results suggest that neural population dynamics in motor cortex are invariant to the number of recorded neurons. By extending functional BMI lifetime, this approach increases the clinical viability of BMIs.
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Affiliation(s)
- Jonathan C Kao
- Department of Electrical Engineering, University of California Los Angeles, Los Angeles, CA, 90095, USA.,Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Stephen I Ryu
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA.,Department of Neurosurgery, Palo Alto Medical Foundation, Palo Alto, CA, 94301, USA
| | - Krishna V Shenoy
- Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA. .,Department of Neurobiology, Stanford University, Stanford, CA, 94305, USA. .,Department of Bioengineering, Stanford University, Stanford, CA, 94305, USA. .,Neurosciences Program, Stanford University, Stanford, CA, 94305, USA. .,Howard Hughes Medical Institute, Stanford University, Stanford, CA, 94305, USA.
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326
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Artoni F, Fanciullacci C, Bertolucci F, Panarese A, Makeig S, Micera S, Chisari C. Unidirectional brain to muscle connectivity reveals motor cortex control of leg muscles during stereotyped walking. Neuroimage 2017; 159:403-416. [PMID: 28782683 PMCID: PMC6698582 DOI: 10.1016/j.neuroimage.2017.07.013] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2017] [Revised: 07/01/2017] [Accepted: 07/09/2017] [Indexed: 01/20/2023] Open
Abstract
In lower mammals, locomotion seems to be mainly regulated by subcortical and spinal networks. On the contrary, recent evidence suggests that in humans the motor cortex is also significantly engaged during complex locomotion tasks. However, a detailed understanding of cortical contribution to locomotion is still lacking especially during stereotyped activities. Here, we show that cortical motor areas finely control leg muscle activation during treadmill stereotyped walking. Using a novel technique based on a combination of Reliable Independent Component Analysis, source localization and effective connectivity, and by combining electroencephalographic (EEG) and electromyographic (EMG) recordings in able-bodied adults we were able to examine for the first time cortical activation patterns and cortico-muscular connectivity including information flow direction. Results not only provided evidence of cortical activity associated with locomotion, but demonstrated significant causal unidirectional drive from contralateral motor cortex to muscles in the swing leg. These insights overturn the traditional view that human cortex has a limited role in the control of stereotyped locomotion, and suggest useful hypotheses concerning mechanisms underlying gait under other conditions. ONE SENTENCE SUMMARY Motor cortex proactively drives contralateral swing leg muscles during treadmill walking, counter to the traditional view of stereotyped human locomotion.
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Affiliation(s)
- Fiorenzo Artoni
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy; Translational Neural Engineering Laboratory, Center for Neuroprosthetics and Institute of Bioengineering, EPFL, Lausanne, Switzerland.
| | - Chiara Fanciullacci
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy; Pisa University Hospital, Pisa, Italy
| | | | | | - Scott Makeig
- Swartz Center for Computational Neuroscience, University of California, San Diego, La Jolla, CA, United States
| | - Silvestro Micera
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy; Translational Neural Engineering Laboratory, Center for Neuroprosthetics and Institute of Bioengineering, EPFL, Lausanne, Switzerland
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327
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Prochazka A. Neurophysiology and neural engineering: a review. J Neurophysiol 2017; 118:1292-1309. [PMID: 28566462 PMCID: PMC5558026 DOI: 10.1152/jn.00149.2017] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 05/30/2017] [Accepted: 05/30/2017] [Indexed: 12/19/2022] Open
Abstract
Neurophysiology is the branch of physiology concerned with understanding the function of neural systems. Neural engineering (also known as neuroengineering) is a discipline within biomedical engineering that uses engineering techniques to understand, repair, replace, enhance, or otherwise exploit the properties and functions of neural systems. In most cases neural engineering involves the development of an interface between electronic devices and living neural tissue. This review describes the origins of neural engineering, the explosive development of methods and devices commencing in the late 1950s, and the present-day devices that have resulted. The barriers to interfacing electronic devices with living neural tissues are many and varied, and consequently there have been numerous stops and starts along the way. Representative examples are discussed. None of this could have happened without a basic understanding of the relevant neurophysiology. I also consider examples of how neural engineering is repaying the debt to basic neurophysiology with new knowledge and insight.
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Affiliation(s)
- Arthur Prochazka
- Department of Physiology, University of Alberta, Edmonton, Alberta, Canada
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328
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Ko WKD, Bezard E. Experimental animal models of Parkinson's disease: A transition from assessing symptomatology to α-synuclein targeted disease modification. Exp Neurol 2017; 298:172-179. [PMID: 28764902 DOI: 10.1016/j.expneurol.2017.07.020] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Accepted: 07/28/2017] [Indexed: 12/13/2022]
Abstract
With the understanding that α-synuclein plays a major role in the pathogenesis of Parkinson's disease (PD), novel animal models have been developed for conducting preclinical research in screening novel disease modifying therapies. Advancements in research techniques in α-synuclein targeted disease modification have utilised methods such as viral mediated expression of human α-synuclein, as well as the inoculation of pathogenic α-synuclein species from Lewy Bodies of PD patients, for accurately modelling progressive self-propagating neurodegeneration. In applying these cutting-edge research tools with sophisticated trial designs in preclinical drug trials, a useful platform has emerged for developing candidate agents with disease modifying actions, promising a greater chance of success for clinical translation. In this article, we describe the transition of well-established animal models of PD symptomatology to newly developed models of PD pathogenesis, with specific focus on methods of viral-mediated and inoculation of pathogenic α-synuclein, that aim to aid scientific translation of neuroprotective strategies.
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Affiliation(s)
- Wai Kin D Ko
- Motac Neuroscience Ltd, Manchester, United Kingdom.
| | - Erwan Bezard
- Motac Neuroscience Ltd, Manchester, United Kingdom; Univ. de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France; CNRS, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France
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329
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Krucoff MO, Zhuang K, MacLeod D, Yin A, Byun YW, Manson RJ, Turner DA, Oliveira L, Lebedev MA. A novel paraplegia model in awake behaving macaques. J Neurophysiol 2017; 118:1800-1808. [PMID: 28701540 DOI: 10.1152/jn.00327.2017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 06/18/2017] [Accepted: 07/06/2017] [Indexed: 01/06/2023] Open
Abstract
Lower limb paralysis from spinal cord injury (SCI) or neurological disease carries a poor prognosis for recovery and remains a large societal burden. Neurophysiological and neuroprosthetic research have the potential to improve quality of life for these patients; however, the lack of an ethical and sustainable nonhuman primate model for paraplegia hinders their advancement. Therefore, our multidisciplinary team developed a way to induce temporary paralysis in awake behaving macaques by creating a fully implantable lumbar epidural catheter-subcutaneous port system that enables easy and reliable targeted drug delivery for sensorimotor blockade. During treadmill walking, aliquots of 1.5% lidocaine with 1:200,000 epinephrine were percutaneously injected into the ports of three rhesus macaques while surface electromyography (EMG) recorded muscle activity from their quadriceps and gastrocnemii. Diminution of EMG amplitude, loss of voluntary leg movement, and inability to bear weight were achieved for 60-90 min in each animal, followed by a complete recovery of function. The monkeys remained alert and cooperative during the paralysis trials and continued to take food rewards, and the ports remained functional after several months. This technique will enable recording from the cortex and/or spinal cord in awake behaving nonhuman primates during the onset, maintenance, and resolution of paraplegia for the first time, thus opening the door to answering basic neurophysiological questions about the acute neurological response to spinal cord injury and recovery. It will also negate the need to permanently injure otherwise high-value research animals for certain experimental paradigms aimed at developing and testing neural interface decoding algorithms for patients with lower extremity dysfunction.NEW & NOTEWORTHY A novel implantable lumbar epidural catheter-subcutaneous port system enables targeted drug delivery and induction of temporary paraplegia in awake, behaving nonhuman primates. Three macaques displayed loss of voluntary leg movement for 60-90 min after injection of lidocaine with epinephrine, followed by a full recovery. This technique for the first time will enable ethical live recording from the proximal central nervous system during the acute onset, maintenance, and resolution of paraplegia.
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Affiliation(s)
- Max O Krucoff
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina;
| | - Katie Zhuang
- Translational Neural Engineering Lab, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - David MacLeod
- Department of Anesthesia, Duke University Medical Center, Durham, North Carolina
| | - Allen Yin
- Department of Biomedical Engineering, Duke University, Durham, North Carolina
| | - Yoon Woo Byun
- Department of Biomedical Engineering, Duke University, Durham, North Carolina
| | - Roberto Jose Manson
- Department of Surgery, Duke University Medical Center, Durham, North Carolina
| | - Dennis A Turner
- Department of Neurosurgery, Duke University Medical Center, Durham, North Carolina.,Research and Surgery Services, Durham Veterans Affairs Medical Center, Durham, North Carolina; and.,Department of Neurobiology, Duke University, Durham, North Carolina
| | - Laura Oliveira
- Department of Biomedical Engineering, Duke University, Durham, North Carolina.,Department of Neurobiology, Duke University, Durham, North Carolina
| | - Mikhail A Lebedev
- Department of Biomedical Engineering, Duke University, Durham, North Carolina.,Department of Neurobiology, Duke University, Durham, North Carolina
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330
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Zheng H, Cao N, Yin Y, Feng W. Stroke recovery and rehabilitation in 2016: a year in review of basic science and clinical science. Stroke Vasc Neurol 2017; 2:222-229. [PMID: 29507783 PMCID: PMC5829939 DOI: 10.1136/svn-2017-000069] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 05/28/2017] [Accepted: 06/12/2017] [Indexed: 12/12/2022] Open
Affiliation(s)
- Haiqing Zheng
- Department of Rehabilitation Medicine, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Ning Cao
- Department of Physical Medicine and Rehabilitation, MosRehab, Elkins Park, Pennsylvania, USA
| | - Yu Yin
- Department of Rehabilitation Medicine, Hebei Provincial General Hospital, Shijiazhuang, China
| | - Wuwei Feng
- Department of Neurology, Medical University of South Carolina, Charleston, SC 29425, USA.,Department of Neurology, Medical University of South Carolina, Charleston, South Carolina, USA
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331
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Kim H. Impact of the localization of dendritic calcium persistent inward current on the input-output properties of spinal motoneuron pool: a computational study. J Appl Physiol (1985) 2017; 123:1166-1187. [PMID: 28684585 DOI: 10.1152/japplphysiol.00034.2017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 07/05/2017] [Accepted: 07/05/2017] [Indexed: 01/23/2023] Open
Abstract
The goal of this study is to investigate how the dendritic Ca-PIC location influences nonlinear input-output properties and depends on the type of motoneurons across the motoneuron pool. A model motoneuron pool consisting of 10 motoneurons was constructed using a recently developed two-compartment modeling approach that reflected key cell type-associated properties experimentally identified. The dendritic excitability and firing output depended systematically on both the PIC location and the motoneuron type. The PIC onset and offset in the current-voltage (I-V) relationship tended to occur at more hyperpolarized voltages as the path length to the PIC channels from the soma increased and as the cell type shifted from high- to low-threshold motoneurons. At the same time, the firing acceleration and frequency hysteresis in the frequency-current (F-I) relationship became faster and larger, respectively. However, the PIC onset-offset hysteresis increased as the path length and the recruitment threshold increased. Furthermore, the gain of frequency-current function before full PIC activation was larger for PIC channels located over distal dendritic regions in low- compared with high-threshold motoneurons. When compared with previously published experimental observations, the modeling concurred when Ca-PIC channels were placed closer to the soma in high- than low-threshold motoneurons in the model motoneuron pool. All of these results suggest that the negative relationship of Ca-PIC location and cell recruitment threshold may underlie the systematic variation in I-V and F-I transformation across the motoneuron pool.NEW & NOTEWORTHY How does the dendritic location of calcium persistent inward current (Ca-PIC) influence dendritic excitability and firing behavior across the spinal motoneuron pool? This issue was investigated developing a model motoneuron pool that reflected key motoneuron type-specific properties experimentally identified. The simulation results point out the negative relationship between the distance of Ca-PIC source from the soma and cell recruitment threshold as a basis underlying the systematic variation in input-output properties of motoneurons over the motoneuron pool.
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Affiliation(s)
- Hojeong Kim
- Convergence Research Institute, DGIST, Daegu, Korea
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332
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Rohani M, Kalsi-Ryan S, Lozano AM, Fasano A. Spinal cord stimulation in primary progressive freezing of gait. Mov Disord 2017; 32:1336-1337. [PMID: 28681922 DOI: 10.1002/mds.27103] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 05/23/2017] [Accepted: 06/04/2017] [Indexed: 12/11/2022] Open
Affiliation(s)
- Mohammad Rohani
- Department of Neurology, Hazrat Rasool Hospital, Iran University of Medical Sciences, Tehran, Iran.,Morton and Gloria Shulman Movement Disorders Clinic and the Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, Toronto, Ontario, Canada.,Division of Neurology, University of Toronto, Toronto, Ontario, Canada
| | - Sukhvinder Kalsi-Ryan
- Krembil Neuroscience Spine Program, Toronto Western Hospital, University of Toronto, Department of Physical Therapy, Toronto, Ontario, Canada
| | - Andres M Lozano
- Division of Neurosurgery, Department of Surgery, Krembil Neuroscience Centre, Toronto Western Hospital, University of Toronto, Canada.,Krembil Research Institute, Toronto, Ontario, Canada
| | - Alfonso Fasano
- Morton and Gloria Shulman Movement Disorders Clinic and the Edmond J. Safra Program in Parkinson's Disease, Toronto Western Hospital, Toronto, Ontario, Canada.,Division of Neurology, University of Toronto, Toronto, Ontario, Canada.,Krembil Research Institute, Toronto, Ontario, Canada
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333
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Hu K, Bounni F, Williams Z. Editorial. Advancement in brain-machine interfaces for patients with tetraplegia: neurosurgical perspective. Neurosurg Focus 2017; 43:E5. [PMID: 28669301 DOI: 10.3171/2017.5.focus17244] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Kejia Hu
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts; and.,Department of Microsurgery, Huashan Hospital, Fudan University, Shanghai, China
| | - Firas Bounni
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts; and
| | - Ziv Williams
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts; and
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334
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Powell MP, Britz WR, Harper JS, Borton DA. An engineered home environment for untethered data telemetry from nonhuman primates. J Neurosci Methods 2017. [PMID: 28648720 DOI: 10.1016/j.jneumeth.2017.06.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND Wireless neural recording technologies now provide untethered access to large populations of neurons in the nonhuman primate brain. Such technologies enable long-term, continuous interrogation of neural circuits and importantly open the door for chronic neurorehabilitation platforms. For example, by providing continuous consistent closed loop feedback from a brain machine interface, the nervous system can leverage plasticity to integrate more effectively into the system than would be possible in short experimental sessions. However, to fully realize this opportunity necessitates the development of experimental environments that do not hinder wireless data transmission. Traditional nonhuman primate metal cage construction, while durable and standardized around the world, prevents data transmission at the frequencies necessary for high-bandwidth data transfer. NEW METHOD To overcome this limitation, we have engineered and constructed a radio-frequency transparent home environment for nonhuman primates using primarily non-conductive materials. RESULTS Computational modeling and empirical testing were performed to demonstrate the behavior of transmitted signals passing through the enclosure. In addition, neural data were successfully recorded from a freely behaving nonhuman primate inside the housing system. COMPARISON WITH EXISTING METHODS Our design outperforms standard metallic home cages by allowing radiation to transmit beyond its boundaries, without significant interference, while simultaneously maintaining the mechanical and operational integrity of existing commercial home cages. CONCLUSIONS Continuous access to neural signals in combination with other bio-potential and kinematic sensors will empower new insights into unrestrained behavior, aid the development of advanced neural prostheses, and enable neurorehabilitation strategies to be employed outside traditional environments.
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Affiliation(s)
- Marc P Powell
- School of Engineering at Brown University, Providence, RI 02912, USA
| | | | - James S Harper
- Division of Biology and Medicine at Brown University, Providence, RI 02912, USA
| | - David A Borton
- School of Engineering at Brown University, Providence, RI 02912, USA; Brown Institute for Brain Sciences (BIBS) at Brown University, Providence, RI 02912, USA; Center for Neurorestoration and Neurotechnology at the Providence Veterans Affairs Medical Center, Providence, RI 02908, USA.
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335
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De Feo V, Boi F, Safaai H, Onken A, Panzeri S, Vato A. State-Dependent Decoding Algorithms Improve the Performance of a Bidirectional BMI in Anesthetized Rats. Front Neurosci 2017; 11:269. [PMID: 28620273 PMCID: PMC5449465 DOI: 10.3389/fnins.2017.00269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 04/26/2017] [Indexed: 11/24/2022] Open
Abstract
Brain-machine interfaces (BMIs) promise to improve the quality of life of patients suffering from sensory and motor disabilities by creating a direct communication channel between the brain and the external world. Yet, their performance is currently limited by the relatively small amount of information that can be decoded from neural activity recorded form the brain. We have recently proposed that such decoding performance may be improved when using state-dependent decoding algorithms that predict and discount the large component of the trial-to-trial variability of neural activity which is due to the dependence of neural responses on the network's current internal state. Here we tested this idea by using a bidirectional BMI to investigate the gain in performance arising from using a state-dependent decoding algorithm. This BMI, implemented in anesthetized rats, controlled the movement of a dynamical system using neural activity decoded from motor cortex and fed back to the brain the dynamical system's position by electrically microstimulating somatosensory cortex. We found that using state-dependent algorithms that tracked the dynamics of ongoing activity led to an increase in the amount of information extracted form neural activity by 22%, with a consequently increase in all of the indices measuring the BMI's performance in controlling the dynamical system. This suggests that state-dependent decoding algorithms may be used to enhance BMIs at moderate computational cost.
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Affiliation(s)
- Vito De Feo
- Neural Computation Laboratory, Istituto Italiano di TecnologiaRovereto, Italy
| | - Fabio Boi
- Neural Computation Laboratory, Istituto Italiano di TecnologiaRovereto, Italy.,Nets3 Laboratory, Department of Neuroscience and Brain Technologies, Istituto Italiano di TecnologiaGenova, Italy
| | - Houman Safaai
- Neural Computation Laboratory, Istituto Italiano di TecnologiaRovereto, Italy.,Department of Neurobiology, Harvard Medical SchoolBoston, MA, United States
| | - Arno Onken
- Neural Computation Laboratory, Istituto Italiano di TecnologiaRovereto, Italy
| | - Stefano Panzeri
- Neural Computation Laboratory, Istituto Italiano di TecnologiaRovereto, Italy
| | - Alessandro Vato
- Neural Computation Laboratory, Istituto Italiano di TecnologiaRovereto, Italy
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336
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Lo YK, Kuan YC, Culaclii S, Kim B, Wang PM, Chang CW, Massachi JA, Zhu M, Chen K, Gad P, Edgerton VR, Liu W. A Fully Integrated Wireless SoC for Motor Function Recovery After Spinal Cord Injury. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2017; 11:497-509. [PMID: 28489550 PMCID: PMC5562024 DOI: 10.1109/tbcas.2017.2679441] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
This paper presents a wirelessly powered, fully integrated system-on-a-chip (SoC) supporting 160-channel stimulation, 16-channel recording, and 48-channel bio-impedance characterization to enable partial motor function recovery through epidural spinal cord electrical stimulation. A wireless transceiver is designed to support quasi full-duplex data telemetry at a data rate of 2 Mb/s. Furthermore, a unique in situ bio-impedance characterization scheme based on time-domain analysis is implemented to derive the Randles cell electrode model of the electrode-electrolyte interface. The SoC supports concurrent stimulation and recording while the high-density stimulator array meets an output compliance voltage of up to ±10 V with versatile stimulus programmability. The SoC consumes 18 mW and occupies a chip area of 5.7 mm × 4.4 mm using 0.18 μm high-voltage CMOS process. In our in vivo rodent experiment, the SoC is used to perform wireless recording of EMG responses while stimulation is applied to enable the standing and stepping of a paralyzed rat. To facilitate the system integration, a novel thin film polymer packaging technique is developed to provide a heterogeneous integration of the SoC, coils, discrete components, and high-density flexible electrode array, resulting in a miniaturized prototype implant with a weight and form factor of 0.7 g and 0.5 cm3, respectively.
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338
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Ajiboye AB, Willett FR, Young DR, Memberg WD, Murphy BA, Miller JP, Walter BL, Sweet JA, Hoyen HA, Keith MW, Peckham PH, Simeral JD, Donoghue JP, Hochberg LR, Kirsch RF. Restoration of reaching and grasping movements through brain-controlled muscle stimulation in a person with tetraplegia: a proof-of-concept demonstration. Lancet 2017; 389:1821-1830. [PMID: 28363483 PMCID: PMC5516547 DOI: 10.1016/s0140-6736(17)30601-3] [Citation(s) in RCA: 419] [Impact Index Per Article: 59.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 01/02/2017] [Accepted: 01/06/2017] [Indexed: 11/01/2022]
Abstract
BACKGROUND People with chronic tetraplegia, due to high-cervical spinal cord injury, can regain limb movements through coordinated electrical stimulation of peripheral muscles and nerves, known as functional electrical stimulation (FES). Users typically command FES systems through other preserved, but unrelated and limited in number, volitional movements (eg, facial muscle activity, head movements, shoulder shrugs). We report the findings of an individual with traumatic high-cervical spinal cord injury who coordinated reaching and grasping movements using his own paralysed arm and hand, reanimated through implanted FES, and commanded using his own cortical signals through an intracortical brain-computer interface (iBCI). METHODS We recruited a participant into the BrainGate2 clinical trial, an ongoing study that obtains safety information regarding an intracortical neural interface device, and investigates the feasibility of people with tetraplegia controlling assistive devices using their cortical signals. Surgical procedures were performed at University Hospitals Cleveland Medical Center (Cleveland, OH, USA). Study procedures and data analyses were performed at Case Western Reserve University (Cleveland, OH, USA) and the US Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center (Cleveland, OH, USA). The study participant was a 53-year-old man with a spinal cord injury (cervical level 4, American Spinal Injury Association Impairment Scale category A). He received two intracortical microelectrode arrays in the hand area of his motor cortex, and 4 months and 9 months later received a total of 36 implanted percutaneous electrodes in his right upper and lower arm to electrically stimulate his hand, elbow, and shoulder muscles. The participant used a motorised mobile arm support for gravitational assistance and to provide humeral abduction and adduction under cortical control. We assessed the participant's ability to cortically command his paralysed arm to perform simple single-joint arm and hand movements and functionally meaningful multi-joint movements. We compared iBCI control of his paralysed arm with that of a virtual three-dimensional arm. This study is registered with ClinicalTrials.gov, number NCT00912041. FINDINGS The intracortical implant occurred on Dec 1, 2014, and we are continuing to study the participant. The last session included in this report was Nov 7, 2016. The point-to-point target acquisition sessions began on Oct 8, 2015 (311 days after implant). The participant successfully cortically commanded single-joint and coordinated multi-joint arm movements for point-to-point target acquisitions (80-100% accuracy), using first a virtual arm and second his own arm animated by FES. Using his paralysed arm, the participant volitionally performed self-paced reaches to drink a mug of coffee (successfully completing 11 of 12 attempts within a single session 463 days after implant) and feed himself (717 days after implant). INTERPRETATION To our knowledge, this is the first report of a combined implanted FES+iBCI neuroprosthesis for restoring both reaching and grasping movements to people with chronic tetraplegia due to spinal cord injury, and represents a major advance, with a clear translational path, for clinically viable neuroprostheses for restoration of reaching and grasping after paralysis. FUNDING National Institutes of Health, Department of Veterans Affairs.
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Affiliation(s)
- A Bolu Ajiboye
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA; School of Medicine, Case Western Reserve University, Cleveland, OH, USA; US Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center, Functional Electrical Stimulation Center of Excellence, Rehabilitation R&D Service, Cleveland, OH, USA.
| | - Francis R Willett
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA; School of Medicine, Case Western Reserve University, Cleveland, OH, USA; US Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center, Functional Electrical Stimulation Center of Excellence, Rehabilitation R&D Service, Cleveland, OH, USA
| | - Daniel R Young
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA; School of Medicine, Case Western Reserve University, Cleveland, OH, USA; US Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center, Functional Electrical Stimulation Center of Excellence, Rehabilitation R&D Service, Cleveland, OH, USA
| | - William D Memberg
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA; School of Medicine, Case Western Reserve University, Cleveland, OH, USA; US Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center, Functional Electrical Stimulation Center of Excellence, Rehabilitation R&D Service, Cleveland, OH, USA
| | - Brian A Murphy
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA; School of Medicine, Case Western Reserve University, Cleveland, OH, USA; US Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center, Functional Electrical Stimulation Center of Excellence, Rehabilitation R&D Service, Cleveland, OH, USA
| | - Jonathan P Miller
- School of Medicine, Case Western Reserve University, Cleveland, OH, USA; US Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center, Functional Electrical Stimulation Center of Excellence, Rehabilitation R&D Service, Cleveland, OH, USA; Department of Neurological Surgery, University Hospitals Cleveland Medical Center, Cleveland, OH, USA
| | - Benjamin L Walter
- School of Medicine, Case Western Reserve University, Cleveland, OH, USA; US Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center, Functional Electrical Stimulation Center of Excellence, Rehabilitation R&D Service, Cleveland, OH, USA; Department of Neurology, University Hospitals Cleveland Medical Center, Cleveland, OH, USA
| | - Jennifer A Sweet
- School of Medicine, Case Western Reserve University, Cleveland, OH, USA; US Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center, Functional Electrical Stimulation Center of Excellence, Rehabilitation R&D Service, Cleveland, OH, USA; Department of Neurological Surgery, University Hospitals Cleveland Medical Center, Cleveland, OH, USA
| | - Harry A Hoyen
- School of Medicine, Case Western Reserve University, Cleveland, OH, USA; Department of Orthopaedics, MetroHealth Medical Center, Cleveland, OH, USA
| | - Michael W Keith
- School of Medicine, Case Western Reserve University, Cleveland, OH, USA; Department of Orthopaedics, MetroHealth Medical Center, Cleveland, OH, USA
| | - P Hunter Peckham
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA; School of Medicine, Case Western Reserve University, Cleveland, OH, USA; US Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center, Functional Electrical Stimulation Center of Excellence, Rehabilitation R&D Service, Cleveland, OH, USA
| | - John D Simeral
- School of Engineering, Brown University, Providence, RI, USA; Brown Institute for Brain Science, Brown University, Providence, RI, USA; Center for Neurorestoration and Neurotechnology, Rehabilitation R&D Service, Department of Veterans Affairs Medical Center, Providence, RI, USA; Department of Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - John P Donoghue
- Brown Institute for Brain Science, Brown University, Providence, RI, USA; Department of Neuroscience, Brown University, Providence, RI, USA; Center for Neurorestoration and Neurotechnology, Rehabilitation R&D Service, Department of Veterans Affairs Medical Center, Providence, RI, USA; Wyss Center for Bio and Neuroengineering, Geneva, Switzerland
| | - Leigh R Hochberg
- School of Engineering, Brown University, Providence, RI, USA; Brown Institute for Brain Science, Brown University, Providence, RI, USA; Center for Neurorestoration and Neurotechnology, Rehabilitation R&D Service, Department of Veterans Affairs Medical Center, Providence, RI, USA; Department of Neurology, Massachusetts General Hospital, Boston, MA, USA; Department of Neurology, Harvard Medical School, Boston, MA, USA
| | - Robert F Kirsch
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA; School of Medicine, Case Western Reserve University, Cleveland, OH, USA; US Department of Veterans Affairs, Louis Stokes Cleveland Veterans Affairs Medical Center, Functional Electrical Stimulation Center of Excellence, Rehabilitation R&D Service, Cleveland, OH, USA; Department of Neurological Surgery, University Hospitals Cleveland Medical Center, Cleveland, OH, USA
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339
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Lebedev MA, Nicolelis MAL. Brain-Machine Interfaces: From Basic Science to Neuroprostheses and Neurorehabilitation. Physiol Rev 2017; 97:767-837. [PMID: 28275048 DOI: 10.1152/physrev.00027.2016] [Citation(s) in RCA: 233] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Brain-machine interfaces (BMIs) combine methods, approaches, and concepts derived from neurophysiology, computer science, and engineering in an effort to establish real-time bidirectional links between living brains and artificial actuators. Although theoretical propositions and some proof of concept experiments on directly linking the brains with machines date back to the early 1960s, BMI research only took off in earnest at the end of the 1990s, when this approach became intimately linked to new neurophysiological methods for sampling large-scale brain activity. The classic goals of BMIs are 1) to unveil and utilize principles of operation and plastic properties of the distributed and dynamic circuits of the brain and 2) to create new therapies to restore mobility and sensations to severely disabled patients. Over the past decade, a wide range of BMI applications have emerged, which considerably expanded these original goals. BMI studies have shown neural control over the movements of robotic and virtual actuators that enact both upper and lower limb functions. Furthermore, BMIs have also incorporated ways to deliver sensory feedback, generated from external actuators, back to the brain. BMI research has been at the forefront of many neurophysiological discoveries, including the demonstration that, through continuous use, artificial tools can be assimilated by the primate brain's body schema. Work on BMIs has also led to the introduction of novel neurorehabilitation strategies. As a result of these efforts, long-term continuous BMI use has been recently implicated with the induction of partial neurological recovery in spinal cord injury patients.
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340
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Urbin MA, Ozdemir RA, Tazoe T, Perez MA. Spike-timing-dependent plasticity in lower-limb motoneurons after human spinal cord injury. J Neurophysiol 2017; 118:2171-2180. [PMID: 28468994 DOI: 10.1152/jn.00111.2017] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 04/24/2017] [Accepted: 04/24/2017] [Indexed: 01/20/2023] Open
Abstract
Recovery of lower-limb function after spinal cord injury (SCI) likely depends on transmission in the corticospinal pathway. Here, we examined whether paired corticospinal-motoneuronal stimulation (PCMS) changes transmission at spinal synapses of lower-limb motoneurons in humans with chronic incomplete SCI and aged-matched controls. We used 200 pairs of stimuli where corticospinal volleys evoked by transcranial magnetic stimulation (TMS) over the leg representation of the motor cortex were timed to arrive at corticospinal-motoneuronal synapses of the tibialis anterior (TA) muscle 2 ms before antidromic potentials evoked in motoneurons by electrical stimulation of the common peroneal nerve (PCMS+) or when antidromic potentials arrived 15 or 28 ms before corticospinal volleys (PCMS-) on separate days. Motor evoked potentials (MEPs) elicited by TMS and electrical stimulation were measured in the TA muscle before and after each stimulation protocol. After PCMS+, the size of MEPs elicited by TMS and electrical stimulation increased for up to 30 min in control and SCI participants. Notably, this was accompanied by increases in TA electromyographic activity and ankle dorsiflexion force in both groups, suggesting that this plasticity has functional implications. After PCMS-, MEPs elicited by TMS and electrical stimulation were suppressed if afferent input from the common peroneal nerve reduced TA MEP size during paired stimulation in both groups. In conclusion, PCMS elicits spike-timing-dependent changes at spinal synapses of lower-limb motoneurons in humans and has potential to improve lower-limb motor output following SCI.NEW & NOTEWORTHY Approaches that aim to enhance corticospinal transmission to lower-limb muscles following spinal cord injury (SCI) are needed. We demonstrate that paired corticomotoneuronal stimulation (PCMS) can enhance plasticity at spinal synapses of lower-limb motoneurons in humans with and without SCI. We propose that PCMS has potential for improving motor output in leg muscles in individuals with damage to the corticospinal tract.
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Affiliation(s)
- M A Urbin
- Department of Neurological Surgery, The Miami Project to Cure Paralysis, University of Miami, Miami, Florida; and Bruce W. Carter Department of Veterans Affairs Medical Center, Miami, Florida
| | - Recep A Ozdemir
- Department of Neurological Surgery, The Miami Project to Cure Paralysis, University of Miami, Miami, Florida; and Bruce W. Carter Department of Veterans Affairs Medical Center, Miami, Florida
| | - Toshiki Tazoe
- Department of Neurological Surgery, The Miami Project to Cure Paralysis, University of Miami, Miami, Florida; and Bruce W. Carter Department of Veterans Affairs Medical Center, Miami, Florida
| | - Monica A Perez
- Department of Neurological Surgery, The Miami Project to Cure Paralysis, University of Miami, Miami, Florida; and Bruce W. Carter Department of Veterans Affairs Medical Center, Miami, Florida
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341
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Rosenfeld JV, Wong YT. Neurobionics and the brain-computer interface: current applications and future horizons. Med J Aust 2017; 206:363-368. [PMID: 28446119 DOI: 10.5694/mja16.01011] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 01/27/2017] [Indexed: 12/17/2022]
Abstract
The brain-computer interface (BCI) is an exciting advance in neuroscience and engineering. In a motor BCI, electrical recordings from the motor cortex of paralysed humans are decoded by a computer and used to drive robotic arms or to restore movement in a paralysed hand by stimulating the muscles in the forearm. Simultaneously integrating a BCI with the sensory cortex will further enhance dexterity and fine control. BCIs are also being developed to: provide ambulation for paraplegic patients through controlling robotic exoskeletons; restore vision in people with acquired blindness; detect and control epileptic seizures; and improve control of movement disorders and memory enhancement. High-fidelity connectivity with small groups of neurons requires microelectrode placement in the cerebral cortex. Electrodes placed on the cortical surface are less invasive but produce inferior fidelity. Scalp surface recording using electroencephalography is much less precise. BCI technology is still in an early phase of development and awaits further technical improvements and larger multicentre clinical trials before wider clinical application and impact on the care of people with disabilities. There are also many ethical challenges to explore as this technology evolves.
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Affiliation(s)
| | - Yan Tat Wong
- Electrical and Computer Systems Engineering, University of Melbourne, Melbourne, VIC
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342
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Furr A, Hardy MA, Barret JP, Barker JH. Surgical, ethical, and psychosocial considerations in human head transplantation. Int J Surg 2017; 41:190-195. [PMID: 28110028 PMCID: PMC5490488 DOI: 10.1016/j.ijsu.2017.01.077] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 01/11/2017] [Accepted: 01/14/2017] [Indexed: 12/14/2022]
Abstract
Transplanting a head and brain is perhaps the final frontier of organ transplantation. The goal of body-to-head transplantation (BHT) is to sustain the life of individuals who suffer from terminal disease, but whose head and brain are healthy. Ideally BHT could provide a lifesaving treatment for several conditions where none currently exists. BHT is no ordinary experiment, to transfer a head to another body involves extraordinarily complex medical challenges as well as ethical and existential dilemmas that were previously confined to the imagination of writers of fiction. The possibility of replacing an incurably ill body with a healthy one tests not only our surgical limits, but also the social and psychological boundaries of physical life and alters what we recognize life to be. The purpose of this target article, the complementary manuscript focused on immunological issues in BHT, and the accompanying Commentaries by scholars and practitioners in medicine, immunology, and bioethics is to review major surgical and psychosocial-ethical and immunological considerations surrounding body-to-head transplantation. We hope that together these ideas will provide readers with a comprehensive overview of the possibilities and challenges associated with BHT and initiate professional discussion and debate through which this new frontier in medicine is considered and approached.
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Affiliation(s)
- Allen Furr
- Haley Center 7018, Auburn University, Auburn, AL, 36849, USA.
| | - Mark A Hardy
- Department of Surgery, Columbia University College of Physicians and Surgeons, 161 Fort, Washington Ave., Herbert Irving Pavilion 5-549, New York, NY, 10032, USA.
| | - Juan P Barret
- University Hospital Vall d'Hebron, Universitat Autonoma de Barcelona, Barcelona, Spain.
| | - John H Barker
- Frankfurt Initiative for Regenerative Medicine, Experimental Orthopedics & Trauma Surgery, J.W. Goethe-University, Friedrichsheim Orthopedic Hospital, Haus 97 B, 1OG, Marienburgstr. 2, 60528, Frankfurt/Main, Germany.
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Liu W, Wang PM, Lo YK. Towards Closed-Loop Neuromodulation: A Wireless Miniaturized Neural Implant SoC. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2017; 10194. [PMID: 30410205 DOI: 10.1117/12.2263566] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
This work reports a platform technology toward the development of closed-loop neuromodulation. A neural implant based on the SoC developed in our laboratory is used as an example to illustrate the necessary functionalities for the efficacious implantable system. We also present an example of using the system to investigate the epidural stimulation for partial motor function recovery after spinal cord injury in a rat model. This hardware-software co-design tool demonstrate its promising potential towards an effective closed-loop neuromodulation for various biomedical applications.
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Affiliation(s)
- Wentai Liu
- University of California, Los Angeles, Los Angeles, CA, USA 90095
| | - Po-Min Wang
- University of California, Los Angeles, Los Angeles, CA, USA 90095
| | - Yi-Kai Lo
- University of California, Los Angeles, Los Angeles, CA, USA 90095
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346
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Surgical Neurostimulation for Spinal Cord Injury. Brain Sci 2017; 7:brainsci7020018. [PMID: 28208601 PMCID: PMC5332961 DOI: 10.3390/brainsci7020018] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 01/30/2017] [Accepted: 02/02/2017] [Indexed: 01/07/2023] Open
Abstract
Traumatic spinal cord injury (SCI) is a devastating neurological condition characterized by a constellation of symptoms including paralysis, paraesthesia, pain, cardiovascular, bladder, bowel and sexual dysfunction. Current treatment for SCI involves acute resuscitation, aggressive rehabilitation and symptomatic treatment for complications. Despite the progress in scientific understanding, regenerative therapies are lacking. In this review, we outline the current state and future potential of invasive and non-invasive neuromodulation strategies including deep brain stimulation (DBS), spinal cord stimulation (SCS), motor cortex stimulation (MCS), transcutaneous direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS) in the context of SCI. We consider the ability of these therapies to address pain, sensorimotor symptoms and autonomic dysregulation associated with SCI. In addition to the potential to make important contributions to SCI treatment, neuromodulation has the added ability to contribute to our understanding of spinal cord neurobiology and the pathophysiology of SCI.
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347
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Silva-dos-Santos A. The Hypothesis of Connecting Two Spinal Cords as a Way of Sharing Information between Two Brains and Nervous Systems. Front Psychol 2017; 8:105. [PMID: 28197119 PMCID: PMC5281600 DOI: 10.3389/fpsyg.2017.00105] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 01/16/2017] [Indexed: 11/18/2022] Open
Abstract
Direct communication between different nervous systems has been recently reported through Brain-to-Brain-Interfaces and brainet. Closed loops systems between the brain and the spinal cord from the same individual have also been demonstrated. However, the connection between different nervous systems through the spinal cord has not yet been considered. This paper raises the hypothesis that connecting two spinal cords (spinal cord - spinal cord connection) is an indirect mean for communication of two brains and a direct way of communication between two nervous systems. A concept of electrical fingerprint of a drug is introduced. The notion of connection between two parts of the same spinal cord to treat a paraplegic patient is also introduced. Possible applications of this technique are discussed in the context of psychology, psychiatry and mental health. Also, it is discussed that external information injected to a spinal cord as well as spinal cord - spinal cord connection can become new tools to (1) study the physiology of the nervous system, (2) model specific behaviors, (3) study and model disease traits (4) treat neuropsychiatric disorders and (5) share information between two nervous systems.
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Affiliation(s)
- Amílcar Silva-dos-Santos
- Department of Psychiatry, Hospital Vila Franca de XiraVila Franca de Xira, Portugal
- Institute of Pharmacology and Neurosciences, Faculty of Medicine, University of LisbonLisbon, Portugal
- Unit of Neurosciences, Institute of Molecular Medicine, University of LisbonLisbon, Portugal
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348
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Krucoff MO, Rahimpour S, Slutzky MW, Edgerton VR, Turner DA. Enhancing Nervous System Recovery through Neurobiologics, Neural Interface Training, and Neurorehabilitation. Front Neurosci 2016; 10:584. [PMID: 28082858 PMCID: PMC5186786 DOI: 10.3389/fnins.2016.00584] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 12/06/2016] [Indexed: 12/21/2022] Open
Abstract
After an initial period of recovery, human neurological injury has long been thought to be static. In order to improve quality of life for those suffering from stroke, spinal cord injury, or traumatic brain injury, researchers have been working to restore the nervous system and reduce neurological deficits through a number of mechanisms. For example, neurobiologists have been identifying and manipulating components of the intra- and extracellular milieu to alter the regenerative potential of neurons, neuro-engineers have been producing brain-machine and neural interfaces that circumvent lesions to restore functionality, and neurorehabilitation experts have been developing new ways to revitalize the nervous system even in chronic disease. While each of these areas holds promise, their individual paths to clinical relevance remain difficult. Nonetheless, these methods are now able to synergistically enhance recovery of native motor function to levels which were previously believed to be impossible. Furthermore, such recovery can even persist after training, and for the first time there is evidence of functional axonal regrowth and rewiring in the central nervous system of animal models. To attain this type of regeneration, rehabilitation paradigms that pair cortically-based intent with activation of affected circuits and positive neurofeedback appear to be required-a phenomenon which raises new and far reaching questions about the underlying relationship between conscious action and neural repair. For this reason, we argue that multi-modal therapy will be necessary to facilitate a truly robust recovery, and that the success of investigational microscopic techniques may depend on their integration into macroscopic frameworks that include task-based neurorehabilitation. We further identify critical components of future neural repair strategies and explore the most updated knowledge, progress, and challenges in the fields of cellular neuronal repair, neural interfacing, and neurorehabilitation, all with the goal of better understanding neurological injury and how to improve recovery.
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Affiliation(s)
- Max O Krucoff
- Department of Neurosurgery, Duke University Medical Center Durham, NC, USA
| | - Shervin Rahimpour
- Department of Neurosurgery, Duke University Medical Center Durham, NC, USA
| | - Marc W Slutzky
- Department of Physiology, Feinberg School of Medicine, Northwestern UniversityChicago, IL, USA; Department of Neurology, Feinberg School of Medicine, Northwestern UniversityChicago, IL, USA
| | - V Reggie Edgerton
- Department of Integrative Biology and Physiology, University of California, Los Angeles Los Angeles, CA, USA
| | - Dennis A Turner
- Department of Neurosurgery, Duke University Medical CenterDurham, NC, USA; Department of Neurobiology, Duke University Medical CenterDurham, NC, USA; Research and Surgery Services, Durham Veterans Affairs Medical CenterDurham, NC, USA
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349
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Affiliation(s)
- Andrew Jackson
- Institute of Neuroscience, Newcastle University, Newcastle NE2 4HH, UK
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350
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Lewis S. Systems neuroscience: Opening the gait. Nat Rev Neurosci 2016; 18:4. [PMID: 27904141 DOI: 10.1038/nrn.2016.166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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