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Wei Y, Marshall AG, McGlone FP, Makdani A, Zhu Y, Yan L, Ren L, Wei G. Human tactile sensing and sensorimotor mechanism: from afferent tactile signals to efferent motor control. Nat Commun 2024; 15:6857. [PMID: 39127772 PMCID: PMC11316806 DOI: 10.1038/s41467-024-50616-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 07/12/2024] [Indexed: 08/12/2024] Open
Abstract
In tactile sensing, decoding the journey from afferent tactile signals to efferent motor commands is a significant challenge primarily due to the difficulty in capturing population-level afferent nerve signals during active touch. This study integrates a finite element hand model with a neural dynamic model by using microneurography data to predict neural responses based on contact biomechanics and membrane transduction dynamics. This research focuses specifically on tactile sensation and its direct translation into motor actions. Evaluations of muscle synergy during in -vivo experiments revealed transduction functions linking tactile signals and muscle activation. These functions suggest similar sensorimotor strategies for grasping influenced by object size and weight. The decoded transduction mechanism was validated by restoring human-like sensorimotor performance on a tendon-driven biomimetic hand. This research advances our understanding of translating tactile sensation into motor actions, offering valuable insights into prosthetic design, robotics, and the development of next-generation prosthetics with neuromorphic tactile feedback.
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Affiliation(s)
- Yuyang Wei
- Department of Engineering Science, University of Oxford, Oxford, OX1 3PJ, UK
- Department of Mechanical, Aerospace and Civil Engineering, The University of Manchester, Manchester, M13 9PL, UK
| | - Andrew G Marshall
- Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, L69 3BX, UK
| | - Francis P McGlone
- Department of Neuroscience and Biomedical Engineering, Aalto University, Otakaari 24, Helsinki, Finland
| | - Adarsh Makdani
- School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, L3 5UX, UK
| | - Yiming Zhu
- Department of Mechanical, Aerospace and Civil Engineering, The University of Manchester, Manchester, M13 9PL, UK
| | - Lingyun Yan
- Department of Mechanical, Aerospace and Civil Engineering, The University of Manchester, Manchester, M13 9PL, UK
| | - Lei Ren
- Department of Mechanical, Aerospace and Civil Engineering, The University of Manchester, Manchester, M13 9PL, UK.
- Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Jilin, China.
| | - Guowu Wei
- School of Science, Engineering and Environment, University of Salford, Manchester, M5 4WT, UK.
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Lamorie-Foote K, Kramer DR, Sundaram S, Cavaleri J, Gilbert ZD, Tang AM, Bashford L, Liu CY, Kellis S, Lee B. Primary somatosensory cortex organization for engineering artificial somatosensation. Neurosci Res 2024; 204:1-13. [PMID: 38278220 DOI: 10.1016/j.neures.2024.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 01/12/2024] [Accepted: 01/17/2024] [Indexed: 01/28/2024]
Abstract
Somatosensory deficits from stroke, spinal cord injury, or other neurologic damage can lead to a significant degree of functional impairment. The primary (SI) and secondary (SII) somatosensory cortices encode information in a medial to lateral organization. SI is generally organized topographically, with more discrete cortical representations of specific body regions. SII regions corresponding to anatomical areas are less discrete and may represent a more functional rather than topographic organization. Human somatosensory research continues to map cortical areas of sensory processing with efforts primarily focused on hand and upper extremity information in SI. However, research into SII and other body regions is lacking. In this review, we synthesize the current state of knowledge regarding the cortical organization of human somatosensation and discuss potential applications for brain computer interface. In addition to accurate individualized mapping of cortical somatosensation, further research is required to uncover the neurophysiological mechanisms of how somatosensory information is encoded in the cortex.
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Affiliation(s)
- Krista Lamorie-Foote
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, United States
| | - Daniel R Kramer
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, United States; Department of Neurological Surgery, University of Colorado School of Medicine, Denver, CO, United States
| | - Shivani Sundaram
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, United States.
| | - Jonathon Cavaleri
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, United States
| | - Zachary D Gilbert
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, United States
| | - Austin M Tang
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, United States; Department of Neurological Surgery, University of Texas at Houston, Houston, TX, United States
| | - Luke Bashford
- Department of Biology and Biological Engineering, T&C Chen Institute for Neuroscience, California Institute of Technology, Pasadena, CA, United States; Department of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Charles Y Liu
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, United States; USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, CA, United States
| | - Spencer Kellis
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, United States; USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, CA, United States
| | - Brian Lee
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, United States; USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, CA, United States
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Fisher LE, Gaunt RA, Huang H. Sensory Restoration for Improved Motor Control of Prostheses. CURRENT OPINION IN BIOMEDICAL ENGINEERING 2023; 28:100498. [PMID: 37860289 PMCID: PMC10583965 DOI: 10.1016/j.cobme.2023.100498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
Somatosensory neuroprostheses are devices with the potential to restore the senses of touch and movement from prosthetic limbs for people with limb amputation or paralysis. By electrically stimulating the peripheral or central nervous system, these devices evoke sensations that appear to emanate from the missing or insensate limb, and when paired with sensors on the prosthesis, they can improve the functionality and embodiment of the prosthesis. There have been major advances in the design of these systems over the past decade, although several important steps remain before they can achieve widespread clinical adoption outside the lab setting. Here, we provide a brief overview of somatosensory neuroprostheses and explores these hurdles and potential next steps towards clinical translation.
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Affiliation(s)
- Lee E. Fisher
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Department of Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Center for Neural Basis of Cognition, Pittsburgh, PA 15213, USA
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Robert A. Gaunt
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Department of Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15213, USA
- Center for Neural Basis of Cognition, Pittsburgh, PA 15213, USA
- Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - He Huang
- UNC/NC State Joint Department of Biomedical Engineering, North Carolina State University, Raleigh, NC 27695, USA
- UNC/NC State Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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Lim J, Wang PT, Bashford L, Kellis S, Shaw SJ, Gong H, Armacost M, Heydari P, Do AH, Andersen RA, Liu CY, Nenadic Z. Suppression of cortical electrostimulation artifacts using pre-whitening and null projection. J Neural Eng 2023; 20:056018. [PMID: 37666246 DOI: 10.1088/1741-2552/acf68b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 09/04/2023] [Indexed: 09/06/2023]
Abstract
Objective.Invasive brain-computer interfaces (BCIs) have shown promise in restoring motor function to those paralyzed by neurological injuries. These systems also have the ability to restore sensation via cortical electrostimulation. Cortical stimulation produces strong artifacts that can obscure neural signals or saturate recording amplifiers. While front-end hardware techniques can alleviate this problem, residual artifacts generally persist and must be suppressed by back-end methods.Approach.We have developed a technique based on pre-whitening and null projection (PWNP) and tested its ability to suppress stimulation artifacts in electroencephalogram (EEG), electrocorticogram (ECoG) and microelectrode array (MEA) signals from five human subjects.Main results.In EEG signals contaminated by narrow-band stimulation artifacts, the PWNP method achieved average artifact suppression between 32 and 34 dB, as measured by an increase in signal-to-interference ratio. In ECoG and MEA signals contaminated by broadband stimulation artifacts, our method suppressed artifacts by 78%-80% and 85%, respectively, as measured by a reduction in interference index. When compared to independent component analysis, which is considered the state-of-the-art technique for artifact suppression, our method achieved superior results, while being significantly easier to implement.Significance.PWNP can potentially act as an efficient method of artifact suppression to enable simultaneous stimulation and recording in bi-directional BCIs to biomimetically restore motor function.
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Affiliation(s)
- Jeffrey Lim
- Department of Biomedical Engineering, University of California Irvine (UCI), Irvine, CA 92697, United States of America
| | - Po T Wang
- Department of Biomedical Engineering, University of California Irvine (UCI), Irvine, CA 92697, United States of America
| | - Luke Bashford
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, United States of America
| | - Spencer Kellis
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, United States of America
- Department of Neurological Surgery, Keck School of Medicine of University of Southern California (USC), Los Angeles, CA 90033, United States of America
- USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, CA 90033, United States of America
| | - Susan J Shaw
- Department of Neurology, Rancho Los Amigos National Rehabilitation Center, Downey, CA 90242, United States of America
- Department of Neurology, Keck School of Medicine of USC, Los Angeles, CA 90033, United States of America
| | - Hui Gong
- Department of Neurology, Rancho Los Amigos National Rehabilitation Center, Downey, CA 90242, United States of America
- Department of Neurology, Keck School of Medicine of USC, Los Angeles, CA 90033, United States of America
| | - Michelle Armacost
- Department of Neurology, Rancho Los Amigos National Rehabilitation Center, Downey, CA 90242, United States of America
- Department of Neurology, Keck School of Medicine of USC, Los Angeles, CA 90033, United States of America
| | - Payam Heydari
- Department of Biomedical Engineering, University of California Irvine (UCI), Irvine, CA 92697, United States of America
- Department of Electrical Engineering and Computer Science, UCI, Irvine, CA 92697, United States of America
| | - An H Do
- Department of Neurology, UCI, Irvine, CA 92697, United States of America
| | - Richard A Andersen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, United States of America
| | - Charles Y Liu
- Department of Neurological Surgery, Keck School of Medicine of University of Southern California (USC), Los Angeles, CA 90033, United States of America
- USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, CA 90033, United States of America
- Department of Neurosurgery, Rancho Los Amigos National Rehabilitation Center, Downey, CA 90242, United States of America
| | - Zoran Nenadic
- Department of Biomedical Engineering, University of California Irvine (UCI), Irvine, CA 92697, United States of America
- Department of Electrical Engineering and Computer Science, UCI, Irvine, CA 92697, United States of America
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Sohn WJ, Lim J, Wang PT, Pu H, Malekzadeh-Arasteh O, Shaw SJ, Armacost M, Gong H, Kellis S, Andersen RA, Liu CY, Heydari P, Nenadic Z, Do AH. Benchtop and bedside validation of a low-cost programmable cortical stimulator in a testbed for bi-directional brain-computer-interface research. Front Neurosci 2023; 16:1075971. [PMID: 36711153 PMCID: PMC9878125 DOI: 10.3389/fnins.2022.1075971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 12/16/2022] [Indexed: 01/15/2023] Open
Abstract
Introduction Bi-directional brain-computer interfaces (BD-BCI) to restore movement and sensation must achieve concurrent operation of recording and decoding of motor commands from the brain and stimulating the brain with somatosensory feedback. Methods A custom programmable direct cortical stimulator (DCS) capable of eliciting artificial sensorimotor response was integrated into an embedded BCI system to form a safe, independent, wireless, and battery powered testbed to explore BD-BCI concepts at a low cost. The BD-BCI stimulator output was tested in phantom brain tissue by assessing its ability to deliver electrical stimulation equivalent to an FDA-approved commercial electrical cortical stimulator. Subsequently, the stimulator was tested in an epilepsy patient with subcortical electrocorticographic (ECoG) implants covering the sensorimotor cortex to assess its ability to elicit equivalent responses as the FDA-approved counterpart. Additional safety features (impedance monitoring, artifact mitigation, and passive and active charge balancing mechanisms) were also implemeneted and tested in phantom brain tissue. Finally, concurrent operation with interleaved stimulation and BCI decoding was tested in a phantom brain as a proof-of-concept operation of BD-BCI system. Results The benchtop prototype BD-BCI stimulator's basic output features (current amplitude, pulse frequency, pulse width, train duration) were validated by demonstrating the output-equivalency to an FDA-approved commercial cortical electrical stimulator (R 2 > 0.99). Charge-neutral stimulation was demonstrated with pulse-width modulation-based correction algorithm preventing steady state voltage deviation. Artifact mitigation achieved a 64.5% peak voltage reduction. Highly accurate impedance monitoring was achieved with R 2 > 0.99 between measured and actual impedance, which in-turn enabled accurate charge density monitoring. An online BCI decoding accuracy of 93.2% between instructional cues and decoded states was achieved while delivering interleaved stimulation. The brain stimulation mapping via ECoG grids in an epilepsy patient showed that the two stimulators elicit equivalent responses. Significance This study demonstrates clinical validation of a fully-programmable electrical stimulator, integrated into an embedded BCI system. This low-cost BD-BCI system is safe and readily applicable as a testbed for BD-BCI research. In particular, it provides an all-inclusive hardware platform that approximates the limitations in a near-future implantable BD-BCI. This successful benchtop/human validation of the programmable electrical stimulator in a BD-BCI system is a critical milestone toward fully-implantable BD-BCI systems.
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Affiliation(s)
- Won Joon Sohn
- Department of Neurology, University of California, Irvine, Irvine, CA, United States
| | - Jeffrey Lim
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, United States
| | - Po T. Wang
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, United States
| | - Haoran Pu
- Department of Electrical Engineering and Computer Science, University of California, Irvine, Irvine, CA, United States
| | - Omid Malekzadeh-Arasteh
- Department of Electrical Engineering and Computer Science, University of California, Irvine, Irvine, CA, United States
| | - Susan J. Shaw
- Department of Neurology, Rancho Los Amigos National Rehabilitation Center, Downey, CA, United States
- Department of Neurology, University of Southern California, Los Angeles, CA, United States
| | - Michelle Armacost
- Department of Neurology, Rancho Los Amigos National Rehabilitation Center, Downey, CA, United States
- Department of Neurology, University of Southern California, Los Angeles, CA, United States
| | - Hui Gong
- Department of Neurology, Rancho Los Amigos National Rehabilitation Center, Downey, CA, United States
- Department of Neurology, University of Southern California, Los Angeles, CA, United States
| | - Spencer Kellis
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Richard A. Andersen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Charles Y. Liu
- Department of Neurosurgery, Rancho Los Amigos National Rehabilitation Center, Downey, CA, United States
- Department of Neurological Surgery, University of Southern California, Los Angeles, CA, United States
| | - Payam Heydari
- Department of Electrical Engineering and Computer Science, University of California, Irvine, Irvine, CA, United States
| | - Zoran Nenadic
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, United States
- Department of Electrical Engineering and Computer Science, University of California, Irvine, Irvine, CA, United States
| | - An H. Do
- Department of Neurology, University of California, Irvine, Irvine, CA, United States
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Gupta A, Vardalakis N, Wagner FB. Neuroprosthetics: from sensorimotor to cognitive disorders. Commun Biol 2023; 6:14. [PMID: 36609559 PMCID: PMC9823108 DOI: 10.1038/s42003-022-04390-w] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 12/19/2022] [Indexed: 01/07/2023] Open
Abstract
Neuroprosthetics is a multidisciplinary field at the interface between neurosciences and biomedical engineering, which aims at replacing or modulating parts of the nervous system that get disrupted in neurological disorders or after injury. Although neuroprostheses have steadily evolved over the past 60 years in the field of sensory and motor disorders, their application to higher-order cognitive functions is still at a relatively preliminary stage. Nevertheless, a recent series of proof-of-concept studies suggest that electrical neuromodulation strategies might also be useful in alleviating some cognitive and memory deficits, in particular in the context of dementia. Here, we review the evolution of neuroprosthetics from sensorimotor to cognitive disorders, highlighting important common principles such as the need for neuroprosthetic systems that enable multisite bidirectional interactions with the nervous system.
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Affiliation(s)
- Ankur Gupta
- grid.462010.1Univ. Bordeaux, CNRS, IMN, UMR 5293, F-33000 Bordeaux, France
| | | | - Fabien B. Wagner
- grid.462010.1Univ. Bordeaux, CNRS, IMN, UMR 5293, F-33000 Bordeaux, France
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Serrano-Amenos C, Heydari P, Liu CY, Do AH, Nenadic Z. Power Budget of a Skull Unit in a Fully-Implantable Brain-Computer Interface: Bio-Heat Model. IEEE Trans Neural Syst Rehabil Eng 2023; 31:4029-4039. [PMID: 37856256 DOI: 10.1109/tnsre.2023.3323916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
The aim of this study is to estimate the maximum power consumption that guarantees the thermal safety of a skull unit (SU). The SU is part of a fully-implantable bi-directional brain computer-interface (BD-BCI) system that aims to restore walking and leg sensation to those with spinal cord injury (SCI). To estimate the SU power budget, we created a bio-heat model using the finite element method (FEM) implemented in COMSOL. To ensure that our predictions were robust against the natural variation of the model's parameters, we also performed a sensitivity analysis. Based on our simulations, we estimated that the SU can nominally consume up to 70 mW of power without raising the surrounding tissues' temperature above the thermal safety threshold of 1°C. When considering the natural variation of the model's parameters, we estimated that the power budget could range between 47 and 81 mW. This power budget should be sufficient to power the basic operations of the SU, including amplification, serialization and A/D conversion of the neural signals, as well as control of cortical stimulation. Determining the power budget is an important specification for the design of the SU and, in turn, the design of a fully-implantable BD-BCI system.
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Obara K, Kaneshige M, Suzuki M, Yokoyama O, Tazoe T, Nishimura Y. Corticospinal interface to restore voluntary control of joint torque in a paralyzed forearm following spinal cord injury in non-human primates. Front Neurosci 2023; 17:1127095. [PMID: 36960166 PMCID: PMC10028188 DOI: 10.3389/fnins.2023.1127095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 01/23/2023] [Indexed: 03/09/2023] Open
Abstract
The corticospinal tract plays a major role in the control of voluntary limb movements, and its damage impedes voluntary limb control. We investigated the feasibility of closed-loop brain-controlled subdural spinal stimulation through a corticospinal interface for the modulation of wrist torque in the paralyzed forearm of monkeys with spinal cord injury at C4/C5. Subdural spinal stimulation of the preserved cervical enlargement activated multiple muscles on the paralyzed forearm and wrist torque in the range from flexion to ulnar-flexion. The magnitude of the evoked torque could be modulated by changing current intensity. We then employed the corticospinal interface designed to detect the firing rate of an arbitrarily selected "linked neuron" in the forearm territory of the primary motor cortex (M1) and convert it in real time to activity-contingent electrical stimulation of a spinal site caudal to the lesion. Linked neurons showed task-related activity that modulated the magnitude of the evoked torque and the activation of multiple muscles depending on the required torque. Unlinked neurons, which were independent of spinal stimulation and located in the vicinity of the linked neurons, exhibited task-related or -unrelated activity. Thus, monkeys were able to modulate the wrist torque of the paralyzed forearm by modulating the firing rate of M1 neurons including unlinked and linked neurons via the corticospinal interface. These results suggest that the corticospinal interface can replace the function of the corticospinal tract after spinal cord injury.
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Affiliation(s)
- Kei Obara
- Neural Prosthetics Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
- Division of Neural Engineering, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
| | - Miki Kaneshige
- Neural Prosthetics Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Michiaki Suzuki
- Neural Prosthetics Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Osamu Yokoyama
- Neural Prosthetics Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Toshiki Tazoe
- Neural Prosthetics Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
| | - Yukio Nishimura
- Neural Prosthetics Project, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
- Division of Neural Engineering, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
- *Correspondence: Yukio Nishimura,
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Lim J, Wang PT, Shaw SJ, Gong H, Armacost M, Liu CY, Do AH, Heydari P, Nenadic Z. Artifact propagation in subdural cortical electrostimulation: Characterization and modeling. Front Neurosci 2022; 16:1021097. [PMID: 36312030 PMCID: PMC9596776 DOI: 10.3389/fnins.2022.1021097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 09/21/2022] [Indexed: 11/13/2022] Open
Abstract
Cortical stimulation via electrocorticography (ECoG) may be an effective method for inducing artificial sensation in bi-directional brain-computer interfaces (BD-BCIs). However, strong electrical artifacts caused by electrostimulation may significantly degrade or obscure neural information. A detailed understanding of stimulation artifact propagation through relevant tissues may improve existing artifact suppression techniques or inspire the development of novel artifact mitigation strategies. Our work thus seeks to comprehensively characterize and model the propagation of artifacts in subdural ECoG stimulation. To this end, we collected and analyzed data from eloquent cortex mapping procedures of four subjects with epilepsy who were implanted with subdural ECoG electrodes. From this data, we observed that artifacts exhibited phase-locking and ratcheting characteristics in the time domain across all subjects. In the frequency domain, stimulation caused broadband power increases, as well as power bursts at the fundamental stimulation frequency and its super-harmonics. The spatial distribution of artifacts followed the potential distribution of an electric dipole with a median goodness-of-fit of R2 = 0.80 across all subjects and stimulation channels. Artifacts as large as ±1,100 μV appeared anywhere from 4.43 to 38.34 mm from the stimulation channel. These temporal, spectral and spatial characteristics can be utilized to improve existing artifact suppression techniques, inspire new strategies for artifact mitigation, and aid in the development of novel cortical stimulation protocols. Taken together, these findings deepen our understanding of cortical electrostimulation and provide critical design specifications for future BD-BCI systems.
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Affiliation(s)
- Jeffrey Lim
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, United States
- *Correspondence: Jeffrey Lim
| | - Po T. Wang
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, United States
| | - Susan J. Shaw
- Rancho Los Amigos National Rehabilitation Center, Downey, CA, United States
| | - Hui Gong
- Rancho Los Amigos National Rehabilitation Center, Downey, CA, United States
| | - Michelle Armacost
- Rancho Los Amigos National Rehabilitation Center, Downey, CA, United States
| | - Charles Y. Liu
- Rancho Los Amigos National Rehabilitation Center, Downey, CA, United States
| | - An H. Do
- Department of Neurology, University of California, Irvine, Irvine, CA, United States
| | - Payam Heydari
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, United States
- Department of Electrical Engineering and Computer Science, University of California, Irvine, Irvine, CA, United States
| | - Zoran Nenadic
- Department of Biomedical Engineering, University of California, Irvine, Irvine, CA, United States
- Department of Electrical Engineering and Computer Science, University of California, Irvine, Irvine, CA, United States
- Zoran Nenadic
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Singh MF, Cole MW, Braver TS, Ching S. Developing control-theoretic objectives for large-scale brain dynamics and cognitive enhancement. ANNUAL REVIEWS IN CONTROL 2022; 54:363-376. [PMID: 38250171 PMCID: PMC10798814 DOI: 10.1016/j.arcontrol.2022.05.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2024]
Abstract
The development of technologies for brain stimulation provides a means for scientists and clinicians to directly actuate the brain and nervous system. Brain stimulation has shown intriguing potential in terms of modifying particular symptom clusters in patients and behavioral characteristics of subjects. The stage is thus set for optimization of these techniques and the pursuit of more nuanced stimulation objectives, including the modification of complex cognitive functions such as memory and attention. Control theory and engineering will play a key role in the development of these methods, guiding computational and algorithmic strategies for stimulation. In particular, realizing this goal will require new development of frameworks that allow for controlling not only brain activity, but also latent dynamics that underlie neural computation and information processing. In the current opinion, we review recent progress in brain stimulation and outline challenges and potential research pathways associated with exogenous control of cognitive function.
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Affiliation(s)
- Matthew F Singh
- Electrical and Systems Engineering, Washington University in St. Louis, St. Louis, 63130, MO, USA
- Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, 07102, NJ, USA
- Psychological and Brain Science, Washington University in St. Louis, St. Louis, 63130, MO, USA
| | - Michael W Cole
- Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, 07102, NJ, USA
| | - Todd S Braver
- Psychological and Brain Science, Washington University in St. Louis, St. Louis, 63130, MO, USA
| | - ShiNung Ching
- Electrical and Systems Engineering, Washington University in St. Louis, St. Louis, 63130, MO, USA
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Borda E, Gaillet V, Airaghi Leccardi MJI, Zollinger EG, Moreira RC, Ghezzi D. Three-dimensional multilayer concentric bipolar electrodes restrict spatial activation in optic nerve stimulation. J Neural Eng 2022; 19. [PMID: 35523152 DOI: 10.1088/1741-2552/ac6d7e] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 05/06/2022] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Intraneural nerve interfaces often operate in a monopolar configuration with a common and distant ground electrode. This configuration leads to a wide spreading of the electric field. Therefore, this approach is suboptimal for intraneural nerve interfaces when selective stimulation is required. APPROACH We designed a multilayer electrode array embedding three-dimensional concentric bipolar electrodes. First, we validated the higher stimulation selectivity of this new electrode array compared to classical monopolar stimulation using simulations. Next, we compared them in-vivo by intraneural stimulation of the rabbit optic nerve and recording evoked potentials in the primary visual cortex. MAIN RESULTS Simulations showed that three-dimensional concentric bipolar electrodes provide a high localisation of the electric field in the tissue so that electrodes are electrically independent even for high electrode density. Experiments in-vivo highlighted that this configuration restricts spatial activation in the visual cortex due to the fewer fibres activated by the electric stimulus in the nerve. SIGNIFICANCE Highly focused electric stimulation is crucial to achieving high selectivity in fibre activation. The multilayer array embedding three-dimensional concentric bipolar electrodes improves selectivity in optic nerve stimulation. This approach is suitable for other neural applications, including bioelectronic medicine.
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Affiliation(s)
- Eleonora Borda
- Medtronic Chair in Neuroengineering, Ecole Polytechnique Federale de Lausanne, EPFL STI IBI LNE, Geneva, 1012, SWITZERLAND
| | - Vivien Gaillet
- Medtronic Chair in Neuroengineering, Ecole Polytechnique Federale de Lausanne, EPFL STI IBI LNE, Geneva, 1012, SWITZERLAND
| | | | - Elodie Geneviève Zollinger
- Medtronic Chair in Neuroengineering, Ecole Polytechnique Federale de Lausanne, EPFL STI IBI LNE, Geneva, 1012, SWITZERLAND
| | | | - Diego Ghezzi
- École Polytechnique Fédérale de Lausanne, Chemin des Mines 9, Geneva, 1202, SWITZERLAND
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12
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Fifer MS, McMullen DP, Osborn LE, Thomas TM, Christie B, Nickl RW, Candrea DN, Pohlmeyer EA, Thompson MC, Anaya MA, Schellekens W, Ramsey NF, Bensmaia SJ, Anderson WS, Wester BA, Crone NE, Celnik PA, Cantarero GL, Tenore FV. Intracortical Somatosensory Stimulation to Elicit Fingertip Sensations in an Individual With Spinal Cord Injury. Neurology 2022; 98:e679-e687. [PMID: 34880087 PMCID: PMC8865889 DOI: 10.1212/wnl.0000000000013173] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 11/19/2021] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND AND OBJECTIVES The restoration of touch to fingers and fingertips is critical to achieving dexterous neuroprosthetic control for individuals with sensorimotor dysfunction. However, localized fingertip sensations have not been evoked via intracortical microstimulation (ICMS). METHODS Using a novel intraoperative mapping approach, we implanted electrode arrays in the finger areas of left and right somatosensory cortex and delivered ICMS over a 2-year period in a human participant with spinal cord injury. RESULTS Stimulation evoked tactile sensations in 8 fingers, including fingertips, spanning both hands. Evoked percepts followed expected somatotopic arrangements. The subject was able to reliably identify up to 7 finger-specific sites spanning both hands in a finger discrimination task. The size of the evoked percepts was on average 33% larger than a finger pad, as assessed via manual markings of a hand image. The size of the evoked percepts increased modestly with increased stimulation intensity, growing 21% as pulse amplitude increased from 20 to 80 µA. Detection thresholds were estimated on a subset of electrodes, with estimates of 9.2 to 35 µA observed, roughly consistent with prior studies. DISCUSSION These results suggest that ICMS can enable the delivery of consistent and localized fingertip sensations during object manipulation by neuroprostheses for individuals with somatosensory deficits. CLINICALTRIALSGOV IDENTIFIER NCT03161067.
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Affiliation(s)
- Matthew S Fifer
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL.
| | - David P McMullen
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Luke E Osborn
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Tessy M Thomas
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Breanne Christie
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Robert W Nickl
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Daniel N Candrea
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Eric A Pohlmeyer
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Margaret C Thompson
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Manuel A Anaya
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Wouter Schellekens
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Nick F Ramsey
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Sliman J Bensmaia
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - William S Anderson
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Brock A Wester
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Nathan E Crone
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Pablo A Celnik
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Gabriela L Cantarero
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
| | - Francesco V Tenore
- From the Research and Exploratory Development Department (M.S.F., L.E.O., B.P.C., E.A.P., M.C.T., F.V.T.), Johns Hopkins University Applied Physics Laboratory, Laurel; National Institute of Mental Health (D.P.M.), NIH, Bethesda; Department of Biomedical Engineering (T.M.T., D.N.C.), Department of Physical Medicine and Rehabilitation (R.W.N., M.A.A., P.A.C., G.L.C.), Department of Neurosurgery (W.S.A.), and Department of Neurology (B.A.W., N.E.C.), Johns Hopkins University, Baltimore, MD; UMC Utrecht Brain Center (W.S., N.F.R.), the Netherlands; and Department of Organismal Biology and Anatomy (S.J.B.), University of Chicago, IL
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13
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Huggins JE, Krusienski D, Vansteensel MJ, Valeriani D, Thelen A, Stavisky S, Norton JJS, Nijholt A, Müller-Putz G, Kosmyna N, Korczowski L, Kapeller C, Herff C, Halder S, Guger C, Grosse-Wentrup M, Gaunt R, Dusang AN, Clisson P, Chavarriaga R, Anderson CW, Allison BZ, Aksenova T, Aarnoutse E. Workshops of the Eighth International Brain-Computer Interface Meeting: BCIs: The Next Frontier. BRAIN-COMPUTER INTERFACES 2022; 9:69-101. [PMID: 36908334 PMCID: PMC9997957 DOI: 10.1080/2326263x.2021.2009654] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Accepted: 11/15/2021] [Indexed: 12/11/2022]
Abstract
The Eighth International Brain-Computer Interface (BCI) Meeting was held June 7-9th, 2021 in a virtual format. The conference continued the BCI Meeting series' interactive nature with 21 workshops covering topics in BCI (also called brain-machine interface) research. As in the past, workshops covered the breadth of topics in BCI. Some workshops provided detailed examinations of specific methods, hardware, or processes. Others focused on specific BCI applications or user groups. Several workshops continued consensus building efforts designed to create BCI standards and increase the ease of comparisons between studies and the potential for meta-analysis and large multi-site clinical trials. Ethical and translational considerations were both the primary topic for some workshops or an important secondary consideration for others. The range of BCI applications continues to expand, with more workshops focusing on approaches that can extend beyond the needs of those with physical impairments. This paper summarizes each workshop, provides background information and references for further study, presents an overview of the discussion topics, and describes the conclusion, challenges, or initiatives that resulted from the interactions and discussion at the workshop.
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Affiliation(s)
- Jane E Huggins
- Department of Physical Medicine and Rehabilitation, Department of Biomedical Engineering, Neuroscience Graduate Program, University of Michigan, Ann Arbor, Michigan, United States 325 East Eisenhower, Room 3017; Ann Arbor, Michigan 48108-5744, 734-936-7177
| | - Dean Krusienski
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA 23219
| | - Mariska J Vansteensel
- UMC Utrecht Brain Center, Dept of Neurosurgery, University Medical Center Utrecht, The Netherlands
| | | | - Antonia Thelen
- eemagine Medical Imaging Solutions GmbH, Berlin, Germany
| | | | - James J S Norton
- National Center for Adaptive Neurotechnologies, US Department of Veterans Affairs, 113 Holland Ave, Albany, NY 12208
| | - Anton Nijholt
- Faculty EEMCS, University of Twente, Enschede, The Netherlands
| | - Gernot Müller-Putz
- Institute of Neural Engineering, GrazBCI Lab, Graz University of Technology, Stremayrgasse 16/4, 8010 Graz, Austria
| | - Nataliya Kosmyna
- Massachusetts Institute of Technology (MIT), Media Lab, E14-548, Cambridge, MA 02139, Unites States
| | | | | | - Christian Herff
- School of Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | | | - Christoph Guger
- g.tec medical engineering GmbH/Guger Technologies OG, Austria, Sierningstrasse 14, 4521 Schiedlberg, Austria, +43725122240-0
| | - Moritz Grosse-Wentrup
- Research Group Neuroinformatics, Faculty of Computer Science, Vienna Cognitive Science Hub, Data Science @ Uni Vienna University of Vienna
| | - Robert Gaunt
- Rehab Neural Engineering Labs, Department of Physical Medicine and Rehabilitation, Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, USA, 3520 5th Ave, Suite 300, Pittsburgh, PA 15213, 412-383-1426
| | - Aliceson Nicole Dusang
- Department of Electrical and Computer Engineering, School of Engineering, Brown University, Carney Institute for Brain Science, Brown University, Providence, RI
- Department of Veterans Affairs Medical Center, Center for Neurorestoration and Neurotechnology, Rehabilitation R&D Service, Providence, RI
- Center for Neurotechnology and Neurorecovery, Neurology, Massachusetts General Hospital, Boston, MA
| | | | - Ricardo Chavarriaga
- IEEE Standards Association Industry Connections group on neurotechnologies for brain-machine interface, Center for Artificial Intelligence, School of Engineering, ZHAW-Zurich University of Applied Sciences, Switzerland, Switzerland
| | - Charles W Anderson
- Department of Computer Science, Molecular, Cellular and Integrative Neurosience Program, Colorado State University, Fort Collins, CO 80523
| | - Brendan Z Allison
- Dept. of Cognitive Science, Mail Code 0515, University of California at San Diego, La Jolla, United States, 619-534-9754
| | - Tetiana Aksenova
- University Grenoble Alpes, CEA, LETI, Clinatec, Grenoble 38000, France
| | - Erik Aarnoutse
- UMC Utrecht Brain Center, Department of Neurology & Neurosurgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
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Abstract
Traditional brain-machine interfaces decode cortical motor commands to control external devices. These commands are the product of higher-level cognitive processes, occurring across a network of brain areas, that integrate sensory information, plan upcoming motor actions, and monitor ongoing movements. We review cognitive signals recently discovered in the human posterior parietal cortex during neuroprosthetic clinical trials. These signals are consistent with small regions of cortex having a diverse role in cognitive aspects of movement control and body monitoring, including sensorimotor integration, planning, trajectory representation, somatosensation, action semantics, learning, and decision making. These variables are encoded within the same population of cells using structured representations that bind related sensory and motor variables, an architecture termed partially mixed selectivity. Diverse cognitive signals provide complementary information to traditional motor commands to enable more natural and intuitive control of external devices.
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Affiliation(s)
- Richard A Andersen
- Division of Biology and Biological Engineering and Tianqiao & Chrissy Chen Brain-Machine Interface Center, California Institute of Technology, Pasadena, California 91125, USA;
- USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, California 90033, USA
| | - Tyson Aflalo
- Division of Biology and Biological Engineering and Tianqiao & Chrissy Chen Brain-Machine Interface Center, California Institute of Technology, Pasadena, California 91125, USA;
| | - Luke Bashford
- Division of Biology and Biological Engineering and Tianqiao & Chrissy Chen Brain-Machine Interface Center, California Institute of Technology, Pasadena, California 91125, USA;
| | - David Bjånes
- Division of Biology and Biological Engineering and Tianqiao & Chrissy Chen Brain-Machine Interface Center, California Institute of Technology, Pasadena, California 91125, USA;
| | - Spencer Kellis
- Division of Biology and Biological Engineering and Tianqiao & Chrissy Chen Brain-Machine Interface Center, California Institute of Technology, Pasadena, California 91125, USA;
- USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, California 90033, USA
- Department of Neurological Surgery, Keck School of Medicine of USC, Los Angeles, California 90033, USA
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15
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Osborn LE, Christie BP, McMullen DP, Nickl RW, Thompson MC, Pawar AS, Thomas TM, Alejandro Anaya M, Crone NE, Wester BA, Bensmaia SJ, Celnik PA, Cantarero GL, Tenore FV, Fifer MS. Intracortical microstimulation of somatosensory cortex enables object identification through perceived sensations. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2021; 2021:6259-6262. [PMID: 34892544 DOI: 10.1109/embc46164.2021.9630450] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Advances in brain-machine interfaces have helped restore function and independence for individuals with sensorimotor deficits; however, providing efficient and effective sensory feedback remains challenging. Intracortical microstimulation (ICMS) of sensorimotor brain regions is a promising technique for providing bioinspired sensory feedback. In a human participant with chronically-implanted microelectrode arrays, we provided ICMS to the primary somatosensory cortex to generate tactile percepts in his hand. In a 3-choice object identification task, the participant identified virtual objects using tactile sensory feedback and no visual information. We evaluated three different stimulation paradigms, each with a different weighting of the grip force and its derivative, to explore the potential benefits of a more bioinspired stimulation strategy. In all paradigms, the participant's ability to identify the objects was above-chance, with object identification accuracy reaching 80% correct when using only sustained grip force feedback and 76.7% when using equal weighting of both sustained grip force and its derivative. These results demonstrate that bioinspired ICMS can provide sensory feedback that is functionally beneficial in sensorimotor tasks. Designing more efficient stimulation paradigms is important because it will allow us to 1) provide safer stimulation delivery methods that reduce overall injected charge without sacrificing function and 2) more effectively transmit sensory information to promote intuitive integration and usage by the human body.
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16
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McMullen DP, Thomas TM, Fifer MS, Candrea DN, Tenore FV, Nickl RW, Pohlmeyer EA, Coogan C, Osborn LE, Schiavi A, Wojtasiewicz T, Gordon CR, Cohen AB, Ramsey NF, Schellekens W, Bensmaia SJ, Cantarero GL, Celnik PA, Wester BA, Anderson WS, Crone NE. Novel intraoperative online functional mapping of somatosensory finger representations for targeted stimulating electrode placement: technical note. J Neurosurg 2021; 135:1493-1500. [PMID: 33770760 DOI: 10.3171/2020.9.jns202675] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 09/29/2020] [Indexed: 11/06/2022]
Abstract
Defining eloquent cortex intraoperatively, traditionally performed by neurosurgeons to preserve patient function, can now help target electrode implantation for restoring function. Brain-machine interfaces (BMIs) have the potential to restore upper-limb motor control to paralyzed patients but require accurate placement of recording and stimulating electrodes to enable functional control of a prosthetic limb. Beyond motor decoding from recording arrays, precise placement of stimulating electrodes in cortical areas associated with finger and fingertip sensations allows for the delivery of sensory feedback that could improve dexterous control of prosthetic hands. In this study, the authors demonstrated the use of a novel intraoperative online functional mapping (OFM) technique with high-density electrocorticography to localize finger representations in human primary somatosensory cortex. In conjunction with traditional pre- and intraoperative targeting approaches, this technique enabled accurate implantation of stimulating microelectrodes, which was confirmed by postimplantation intracortical stimulation of finger and fingertip sensations. This work demonstrates the utility of intraoperative OFM and will inform future studies of closed-loop BMIs in humans.
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Affiliation(s)
- David P McMullen
- 1National Institute of Mental Health, National Institutes of Health, Bethesda
| | | | - Matthew S Fifer
- 3Research and Exploratory Development Department, Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland
| | | | - Francesco V Tenore
- 3Research and Exploratory Development Department, Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland
| | | | - Eric A Pohlmeyer
- 3Research and Exploratory Development Department, Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland
| | | | - Luke E Osborn
- 3Research and Exploratory Development Department, Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland
| | | | | | - Chad R Gordon
- 8Plastic and Reconstructive Surgery, Johns Hopkins University, Baltimore
| | - Adam B Cohen
- 3Research and Exploratory Development Department, Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland
- 5Neurology
| | - Nick F Ramsey
- 9UMC Utrecht Brain Center, Utrecht, The Netherlands; and
| | | | - Sliman J Bensmaia
- 10Department of Organismal Biology and Anatomy, University of Chicago, Illinois
| | | | | | - Brock A Wester
- 3Research and Exploratory Development Department, Johns Hopkins University Applied Physics Laboratory, Laurel, Maryland
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17
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Chandrasekaran S, Fifer M, Bickel S, Osborn L, Herrero J, Christie B, Xu J, Murphy RKJ, Singh S, Glasser MF, Collinger JL, Gaunt R, Mehta AD, Schwartz A, Bouton CE. Historical perspectives, challenges, and future directions of implantable brain-computer interfaces for sensorimotor applications. Bioelectron Med 2021; 7:14. [PMID: 34548098 PMCID: PMC8456563 DOI: 10.1186/s42234-021-00076-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 08/29/2021] [Indexed: 11/10/2022] Open
Abstract
Almost 100 years ago experiments involving electrically stimulating and recording from the brain and the body launched new discoveries and debates on how electricity, movement, and thoughts are related. Decades later the development of brain-computer interface technology began, which now targets a wide range of applications. Potential uses include augmentative communication for locked-in patients and restoring sensorimotor function in those who are battling disease or have suffered traumatic injury. Technical and surgical challenges still surround the development of brain-computer technology, however, before it can be widely deployed. In this review we explore these challenges, historical perspectives, and the remarkable achievements of clinical study participants who have bravely forged new paths for future beneficiaries.
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Affiliation(s)
- Santosh Chandrasekaran
- Neural Bypass and Brain Computer Interface Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
| | - Matthew Fifer
- Research and Exploratory Development Department, Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Stephan Bickel
- The Human Brain Mapping Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
- Department of Neurosurgery, Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
- Department of Neurology, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
| | - Luke Osborn
- Research and Exploratory Development Department, Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Jose Herrero
- The Human Brain Mapping Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
| | - Breanne Christie
- Research and Exploratory Development Department, Johns Hopkins University Applied Physics Laboratory, Laurel, MD, USA
| | - Junqian Xu
- Departments of Radiology and Psychiatry, Baylor College of Medicine, Houston, TX, USA
| | - Rory K J Murphy
- Department of Neurosurgery, Barrow Neurological Institute, St. Joseph's Hospital and Medical Center, Phoenix, AZ, USA
| | - Sandeep Singh
- Good Shepherd Rehabilitation Hospital, Allentown, PA, USA
| | - Matthew F Glasser
- Departments of Radiology and Neuroscience, Washington University in St Louis, Saint Louis, MO, USA
| | - Jennifer L Collinger
- Rehabilitation Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, USA
| | - Robert Gaunt
- Rehabilitation Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA, USA
| | - Ashesh D Mehta
- The Human Brain Mapping Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
- Department of Neurosurgery, Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
| | - Andrew Schwartz
- McGowan Institute of Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Chad E Bouton
- Neural Bypass and Brain Computer Interface Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA.
- Department of Molecular Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA.
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18
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Driscoll N, Erickson B, Murphy BB, Richardson AG, Robbins G, Apollo NV, Mentzelopoulos G, Mathis T, Hantanasirisakul K, Bagga P, Gullbrand SE, Sergison M, Reddy R, Wolf JA, Chen HI, Lucas TH, Dillingham T, Davis KA, Gogotsi Y, Medaglia JD, Vitale F. MXene-infused bioelectronic interfaces for multiscale electrophysiology and stimulation. Sci Transl Med 2021; 13:eabf8629. [PMID: 34550728 PMCID: PMC8722432 DOI: 10.1126/scitranslmed.abf8629] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Soft bioelectronic interfaces for mapping and modulating excitable networks at high resolution and at large scale can enable paradigm-shifting diagnostics, monitoring, and treatment strategies. Yet, current technologies largely rely on materials and fabrication schemes that are expensive, do not scale, and critically limit the maximum attainable resolution and coverage. Solution processing is a cost-effective manufacturing alternative, but biocompatible conductive inks matching the performance of conventional metals are lacking. Here, we introduce MXtrodes, a class of soft, high-resolution, large-scale bioelectronic interfaces enabled by Ti3C2 MXene (a two-dimensional transition metal carbide nanomaterial) and scalable solution processing. We show that the electrochemical properties of MXtrodes exceed those of conventional materials and do not require conductive gels when used in epidermal electronics. Furthermore, we validate MXtrodes in applications ranging from mapping large-scale neuromuscular networks in humans to cortical neural recording and microstimulation in swine and rodent models. Last, we demonstrate that MXtrodes are compatible with standard clinical neuroimaging modalities.
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Affiliation(s)
- Nicolette Driscoll
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA 19104, USA
| | - Brian Erickson
- Department of Psychology, Drexel University, Philadelphia, PA 19104, USA
| | - Brendan B. Murphy
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA 19104, USA
| | - Andrew G. Richardson
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Gregory Robbins
- Department of Physical Medicine and Rehabilitation, University of Pennsylvania, PA 19104, USA
| | - Nicholas V. Apollo
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA 19104, USA
| | - Georgios Mentzelopoulos
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA 19104, USA
| | - Tyler Mathis
- Department of Materials Science and Engineering, Drexel University, Philadelphia, PA 19104, USA
- A.J. Drexel Nanomaterials Institute, Drexel University, Philadelphia, PA 19104, USA
| | - Kanit Hantanasirisakul
- Department of Materials Science and Engineering, Drexel University, Philadelphia, PA 19104, USA
- A.J. Drexel Nanomaterials Institute, Drexel University, Philadelphia, PA 19104, USA
| | - Puneet Bagga
- Department of Radiology, Center for Magnetic Resonance and Optical Imaging, University of Pennsylvania, Philadelphia, PA 19104, USA
- Diagnostic Imaging, St Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | - Sarah E. Gullbrand
- Translational Musculoskeletal Research Center, Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA 19104, USA
- McKay Orthopaedic Research Laboratory, Department of Orthopaedic Surgery, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Matthew Sergison
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA 19104, USA
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Ravinder Reddy
- Department of Radiology, Center for Magnetic Resonance and Optical Imaging, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - John A. Wolf
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA 19104, USA
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - H. Isaac Chen
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA 19104, USA
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Timothy H. Lucas
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Timothy Dillingham
- Department of Physical Medicine and Rehabilitation, University of Pennsylvania, PA 19104, USA
| | - Kathryn A. Davis
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Yury Gogotsi
- Department of Materials Science and Engineering, Drexel University, Philadelphia, PA 19104, USA
- A.J. Drexel Nanomaterials Institute, Drexel University, Philadelphia, PA 19104, USA
| | - John D. Medaglia
- Department of Psychology, Drexel University, Philadelphia, PA 19104, USA
- Department of Neurology, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Neurology, Drexel University, Philadelphia, PA 19104, USA
| | - Flavia Vitale
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Neuroengineering and Therapeutics, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Neurotrauma, Neurodegeneration, and Restoration, Corporal Michael J. Crescenz Veterans Affairs Medical Center, Philadelphia, PA 19104, USA
- Department of Physical Medicine and Rehabilitation, University of Pennsylvania, PA 19104, USA
- Department of Neurology, University of Pennsylvania, Philadelphia, PA 19104, USA
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19
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Chandrasekaran S, Bickel S, Herrero JL, Kim JW, Markowitz N, Espinal E, Bhagat NA, Ramdeo R, Xu J, Glasser MF, Bouton CE, Mehta AD. Evoking highly focal percepts in the fingertips through targeted stimulation of sulcal regions of the brain for sensory restoration. Brain Stimul 2021; 14:1184-1196. [PMID: 34358704 PMCID: PMC8884403 DOI: 10.1016/j.brs.2021.07.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 06/29/2021] [Accepted: 07/19/2021] [Indexed: 01/06/2023] Open
Abstract
Background: Paralysis and neuropathy, affecting millions of people worldwide, can be accompanied by significant loss of somatosensation. With tactile sensation being central to achieving dexterous movement, brain-computer interface (BCI) researchers have used intracortical and cortical surface electrical stimulation to restore somatotopically-relevant sensation to the hand. However, these approaches are restricted to stimulating the gyral areas of the brain. Since representation of distal regions of the hand extends into the sulcal regions of human primary somatosensory cortex (S1), it has been challenging to evoke sensory percepts localized to the fingertips. Objective/hypothesis: Targeted stimulation of sulcal regions of S1, using stereoelectroencephalography (SEEG) depth electrodes, can evoke focal sensory percepts in the fingertips. Methods: Two participants with intractable epilepsy received cortical stimulation both at the gyri via high-density electrocorticography (HD-ECoG) grids and in the sulci via SEEG depth electrode leads. We characterized the evoked sensory percepts localized to the hand. Results: We show that highly focal percepts can be evoked in the fingertips of the hand through sulcal stimulation. fMRI, myelin content, and cortical thickness maps from the Human Connectome Project elucidated specific cortical areas and sub-regions within S1 that evoked these focal percepts. Within-participant comparisons showed that percepts evoked by sulcal stimulation via SEEG electrodes were significantly more focal (80% less area; p = 0.02) and localized to the fingertips more often, than by gyral stimulation via HD-ECoG electrodes. Finally, sulcal locations with consistent modulation of high-frequency neural activity during mechanical tactile stimulation of the fingertips showed the same somatotopic correspondence as cortical stimulation. Conclusions: Our findings indicate minimally invasive sulcal stimulation via SEEG electrodes could be a clinically viable approach to restoring sensation.
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Affiliation(s)
- Santosh Chandrasekaran
- Neural Bypass and Brain Computer Interface Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA.
| | - Stephan Bickel
- The Human Brain Mapping Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA; Department of Neurosurgery, Northwell, Manhasset, NY, USA; Department of Neurology, Donald and Barbara Zucker School of Medicine at Hofstra, Northwell, Manhasset, NY, USA
| | - Jose L Herrero
- The Human Brain Mapping Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA; Department of Neurosurgery, Northwell, Manhasset, NY, USA
| | - Joo-Won Kim
- Departments of Radiology and Psychiatry, Baylor College of Medicine, Houston, TX, USA
| | - Noah Markowitz
- The Human Brain Mapping Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
| | - Elizabeth Espinal
- The Human Brain Mapping Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
| | - Nikunj A Bhagat
- Neural Bypass and Brain Computer Interface Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
| | - Richard Ramdeo
- Neural Bypass and Brain Computer Interface Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
| | - Junqian Xu
- Departments of Radiology and Psychiatry, Baylor College of Medicine, Houston, TX, USA
| | - Matthew F Glasser
- Departments of Radiology and Neuroscience, Washington University in St Louis, Saint Louis, MO, USA
| | - Chad E Bouton
- Neural Bypass and Brain Computer Interface Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA; Department of Molecular Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA.
| | - Ashesh D Mehta
- The Human Brain Mapping Laboratory, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA; Department of Neurosurgery, Northwell, Manhasset, NY, USA
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20
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Shokur S, Mazzoni A, Schiavone G, Weber DJ, Micera S. A modular strategy for next-generation upper-limb sensory-motor neuroprostheses. MED 2021; 2:912-937. [DOI: 10.1016/j.medj.2021.05.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 04/28/2021] [Accepted: 05/10/2021] [Indexed: 02/06/2023]
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21
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Versteeg C, Rosenow JM, Bensmaia SJ, Miller LE. Encoding of limb state by single neurons in the cuneate nucleus of awake monkeys. J Neurophysiol 2021; 126:693-706. [PMID: 34010577 PMCID: PMC8409958 DOI: 10.1152/jn.00568.2020] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 05/13/2021] [Accepted: 05/13/2021] [Indexed: 12/24/2022] Open
Abstract
The cuneate nucleus (CN) is among the first sites along the neuraxis where proprioceptive signals can be integrated, transformed, and modulated. The objective of the study was to characterize the proprioceptive representations in CN. To this end, we recorded from single CN neurons in three monkeys during active reaching and passive limb perturbation. We found that many neurons exhibited responses that were tuned approximately sinusoidally to limb movement direction, as has been found for other sensorimotor neurons. The distribution of their preferred directions (PDs) was highly nonuniform and resembled that of muscle spindles within individual muscles, suggesting that CN neurons typically receive inputs from only a single muscle. We also found that the responses of proprioceptive CN neurons tended to be modestly amplified during active reaching movements compared to passive limb perturbations, in contrast to cutaneous CN neurons whose responses were not systematically different in the active and passive conditions. Somatosensory signals thus seem to be subject to a "spotlighting" of relevant sensory information rather than uniform suppression as has been suggested previously.NEW & NOTEWORTHY The cuneate nucleus (CN) is the somatosensory gateway into the brain, and only recently has it been possible to record these signals from an awake animal. We recorded single CN neurons in monkeys. Proprioceptive CN neurons appear to receive input from very few muscles, and their sensitivity to movement changes reliably during reaching relative to passive arm perturbations. Sensitivity is generally increased, but not exclusively so, as though CN "spotlights" critical proprioceptive information during reaching.
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Affiliation(s)
- Christopher Versteeg
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois
| | - Joshua M Rosenow
- Department of Neurology, Northwestern University, Chicago, Illinois
- Department of Neurological Surgery, Northwestern University, Chicago, Illinois
- Department of Physical Medicine and Rehabilitation, Northwestern University, Chicago, Illinois
| | - Sliman J Bensmaia
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois
- Committee on Computational Neuroscience, University of Chicago, Chicago, Illinois
- Grossman Institute of Neuroscience, Quantitative Biology, and Human Behavior, University of Chicago, Chicago, Illinois
| | - Lee E Miller
- Department of Biomedical Engineering, Northwestern University, Evanston, Illinois
- Department of Physical Medicine and Rehabilitation, Northwestern University, Chicago, Illinois
- Shirley Ryan AbilityLab, Chicago, Illinois
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
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22
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Szymanski LJ, Kellis S, Liu CY, Jones KT, Andersen RA, Commins D, Lee B, McCreery DB, Miller CA. Neuropathological effects of chronically implanted, intracortical microelectrodes in a tetraplegic patient. J Neural Eng 2021; 18. [PMID: 34314384 DOI: 10.1088/1741-2552/ac127e] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 07/08/2021] [Indexed: 11/12/2022]
Abstract
Objective.Intracortical microelectrode arrays (MEA) can be used as part of a brain-machine interface system to provide sensory feedback control of an artificial limb to assist persons with tetraplegia. Variability in functionality of electrodes has been reported but few studies in humans have examined the impact of chronic brain tissue responses revealed postmortem on electrode performancein vivo. Approach.In a tetraplegic man, recording MEAs were implanted into the anterior intraparietal area and Brodmann's area 5 (BA5) of the posterior parietal cortex and a recording and stimulation array was implanted in BA1 of the primary somatosensory cortex (S1). The participant expired from unrelated causes seven months after MEA implantation. The underlying tissue of two of the three devices was processed for histology and electrophysiological recordings were assessed.Main results.Recordings of neuronal activity were obtained from all three MEAs despite meningeal encapsulation. However, the S1 array had a greater encapsulation, yielded lower signal quality than the other arrays and failed to elicit somatosensory percepts with electrical stimulation. Histological examination of tissues underlying S1 and BA5 implant sites revealed localized leptomeningeal proliferation and fibrosis, lymphocytic infiltrates, astrogliosis, and foreign body reaction around the electrodes. The BA5 recording site showed focal cerebral microhemorrhages and leptomeningeal vascular ectasia. The S1 site showed focal tissue damage including vascular recanalization, neuronal loss, and extensive subcortical white matter necrosis. The tissue response at the S1 site included hemorrhagic-induced injury suggesting a likely mechanism for reduced function of the S1 implant.Significance.Our findings are similar to those from animal studies with chronic intracortical implants and suggest that vascular disruption and microhemorrhage during device implantation are important contributors to overall array and individual electrode performance and should be a topic for future device development to mitigate tissue responses. Neurosurgical considerations are also discussed.
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Affiliation(s)
- Linda J Szymanski
- Department of Pathology, Keck USC School of Medicine, Los Angeles, CA, United States of America.,Department of Pathology and Laboratory Medicine, Children's Hospital of Los Angeles, Los Angeles, CA, United States of America
| | - Spencer Kellis
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States of America.,Tianqiao and Chrissy Chen Brain-Machine Interface Center, Chen Institute for Neuroscience, California Institute of Technology, Pasadena, CA, United States of America.,Department of Neurosurgery, Keck USC School of Medicine, Los Angeles, CA, United States of America.,USC Neurorestoration Center, Keck USC School of Medicine, Los Angeles, CA, United States of America
| | - Charles Y Liu
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States of America.,Department of Neurosurgery, Keck USC School of Medicine, Los Angeles, CA, United States of America.,USC Neurorestoration Center, Keck USC School of Medicine, Los Angeles, CA, United States of America
| | - Kymry T Jones
- Department of Pathology, Keck USC School of Medicine, Los Angeles, CA, United States of America
| | - Richard A Andersen
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States of America.,Tianqiao and Chrissy Chen Brain-Machine Interface Center, Chen Institute for Neuroscience, California Institute of Technology, Pasadena, CA, United States of America
| | - Deborah Commins
- Department of Pathology, Keck USC School of Medicine, Los Angeles, CA, United States of America
| | - Brian Lee
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States of America.,Department of Neurosurgery, Keck USC School of Medicine, Los Angeles, CA, United States of America.,USC Neurorestoration Center, Keck USC School of Medicine, Los Angeles, CA, United States of America
| | - Douglas B McCreery
- Huntington Medical Research Institute, Pasadena, CA, United States of America
| | - Carol A Miller
- Department of Pathology, Keck USC School of Medicine, Los Angeles, CA, United States of America
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23
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Flesher SN, Downey JE, Weiss JM, Hughes CL, Herrera AJ, Tyler-Kabara EC, Boninger ML, Collinger JL, Gaunt RA. A brain-computer interface that evokes tactile sensations improves robotic arm control. Science 2021; 372:831-836. [PMID: 34016775 PMCID: PMC8715714 DOI: 10.1126/science.abd0380] [Citation(s) in RCA: 159] [Impact Index Per Article: 53.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 03/25/2021] [Indexed: 12/14/2022]
Abstract
Prosthetic arms controlled by a brain-computer interface can enable people with tetraplegia to perform functional movements. However, vision provides limited feedback because information about grasping objects is best relayed through tactile feedback. We supplemented vision with tactile percepts evoked using a bidirectional brain-computer interface that records neural activity from the motor cortex and generates tactile sensations through intracortical microstimulation of the somatosensory cortex. This enabled a person with tetraplegia to substantially improve performance with a robotic limb; trial times on a clinical upper-limb assessment were reduced by half, from a median time of 20.9 to 10.2 seconds. Faster times were primarily due to less time spent attempting to grasp objects, revealing that mimicking known biological control principles results in task performance that is closer to able-bodied human abilities.
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Affiliation(s)
- Sharlene N Flesher
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
| | - John E Downey
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
- Department of Organismal Biology, University of Chicago, Chicago, IL, USA
| | - Jeffrey M Weiss
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
| | - Christopher L Hughes
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
| | - Angelica J Herrera
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
| | | | - Michael L Boninger
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, USA
- VA Center of Excellence, Department of Veterans Affairs, Pittsburgh, PA, USA
| | - Jennifer L Collinger
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA.
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
- VA Center of Excellence, Department of Veterans Affairs, Pittsburgh, PA, USA
| | - Robert A Gaunt
- Rehab Neural Engineering Labs, University of Pittsburgh, Pittsburgh, PA, USA.
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
- Center for the Neural Basis of Cognition, Pittsburgh, PA, USA
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, USA
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24
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Abstract
Neural devices have the capacity to enable users to regain abilities lost due to disease or injury - for instance, a deep brain stimulator (DBS) that allows a person with Parkinson's disease to regain the ability to fluently perform movements or a Brain Computer Interface (BCI) that enables a person with spinal cord injury to control a robotic arm. While users recognize and appreciate the technologies' capacity to maintain or restore their capabilities, the neuroethics literature is replete with examples of concerns expressed about agentive capacities: A perceived lack of control over the movement of a robotic arm might result in an altered sense of feeling responsible for that movement. Clinicians or researchers being able to record and access detailed information of a person's brain might raise privacy concerns. A disconnect between previous, current, and future understandings of the self might result in a sense of alienation. The ability to receive and interpret sensory feedback might change whether someone trusts the implanted device or themselves. Inquiries into the nature of these concerns and how to mitigate them has produced scholarship that often emphasizes one issue - responsibility, privacy, authenticity, or trust - selectively. However, we believe that examining these ethical dimensions separately fails to capture a key aspect of the experience of living with a neural device. In exploring their interrelations, we argue that their mutual significance for neuroethical research can be adequately captured if they are described under a unified heading of agency. On these grounds, we propose an "Agency Map" which brings together the diverse neuroethical dimensions and their interrelations into a comprehensive framework. With this, we offer a theoretically-grounded approach to understanding how these various dimensions are interwoven in an individual's experience of agency.
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Affiliation(s)
| | | | | | | | - Eran Klein
- University of Washington
- Oregon Health and Science University
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Kramer DR, Lamorie-Foote K, Barbaro M, Lee MB, Peng T, Gogia A, Nune G, Liu CY, Kellis SS, Lee B. Utility and lower limits of frequency detection in surface electrode stimulation for somatosensory brain-computer interface in humans. Neurosurg Focus 2021; 48:E2. [PMID: 32006952 DOI: 10.3171/2019.11.focus19696] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Accepted: 11/04/2019] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Stimulation of the primary somatosensory cortex (S1) has been successful in evoking artificial somatosensation in both humans and animals, but much is unknown about the optimal stimulation parameters needed to generate robust percepts of somatosensation. In this study, the authors investigated frequency as an adjustable stimulation parameter for artificial somatosensation in a closed-loop brain-computer interface (BCI) system. METHODS Three epilepsy patients with subdural mini-electrocorticography grids over the hand area of S1 were asked to compare the percepts elicited with different stimulation frequencies. Amplitude, pulse width, and duration were held constant across all trials. In each trial, subjects experienced 2 stimuli and reported which they thought was given at a higher stimulation frequency. Two paradigms were used: first, 50 versus 100 Hz to establish the utility of comparing frequencies, and then 2, 5, 10, 20, 50, or 100 Hz were pseudorandomly compared. RESULTS As the magnitude of the stimulation frequency was increased, subjects described percepts that were "more intense" or "faster." Cumulatively, the participants achieved 98.0% accuracy when comparing stimulation at 50 and 100 Hz. In the second paradigm, the corresponding overall accuracy was 73.3%. If both tested frequencies were less than or equal to 10 Hz, accuracy was 41.7% and increased to 79.4% when one frequency was greater than 10 Hz (p = 0.01). When both stimulation frequencies were 20 Hz or less, accuracy was 40.7% compared with 91.7% when one frequency was greater than 20 Hz (p < 0.001). Accuracy was 85% in trials in which 50 Hz was the higher stimulation frequency. Therefore, the lower limit of detection occurred at 20 Hz, and accuracy decreased significantly when lower frequencies were tested. In trials testing 10 Hz versus 20 Hz, accuracy was 16.7% compared with 85.7% in trials testing 20 Hz versus 50 Hz (p < 0.05). Accuracy was greater than chance at frequency differences greater than or equal to 30 Hz. CONCLUSIONS Frequencies greater than 20 Hz may be used as an adjustable parameter to elicit distinguishable percepts. These findings may be useful in informing the settings and the degrees of freedom achievable in future BCI systems.
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Affiliation(s)
- Daniel R Kramer
- Departments of1Neurosurgery and.,2Neurorestoration Center, and
| | | | - Michael Barbaro
- 3Keck School of Medicine, University of Southern California, Los Angeles; and
| | - Morgan B Lee
- 3Keck School of Medicine, University of Southern California, Los Angeles; and
| | - Terrance Peng
- 3Keck School of Medicine, University of Southern California, Los Angeles; and
| | - Angad Gogia
- 3Keck School of Medicine, University of Southern California, Los Angeles; and
| | | | - Charles Y Liu
- Departments of1Neurosurgery and.,2Neurorestoration Center, and
| | - Spencer S Kellis
- 2Neurorestoration Center, and.,5Department of Biology and Biological Engineering and.,6Tianqiao and Chrissy Chen Brain-Machine Interface Center, California Institute of Technology, Pasadena, California
| | - Brian Lee
- Departments of1Neurosurgery and.,2Neurorestoration Center, and
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Paek AY, Brantley JA, Sujatha Ravindran A, Nathan K, He Y, Eguren D, Cruz-Garza JG, Nakagome S, Wickramasuriya DS, Chang J, Rashed-Al-Mahfuz M, Amin MR, Bhagat NA, Contreras-Vidal JL. A Roadmap Towards Standards for Neurally Controlled End Effectors. IEEE OPEN JOURNAL OF ENGINEERING IN MEDICINE AND BIOLOGY 2021; 2:84-90. [PMID: 35402986 PMCID: PMC8979628 DOI: 10.1109/ojemb.2021.3059161] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/24/2020] [Accepted: 02/09/2021] [Indexed: 12/02/2022] Open
Abstract
The control and manipulation of various types of end effectors such as powered exoskeletons, prostheses, and ‘neural’ cursors by brain-machine interface (BMI) systems has been the target of many research projects. A seamless “plug and play” interface between any BMI and end effector is desired, wherein similar user's intent cause similar end effectors to behave identically. This report is based on the outcomes of an IEEE Standards Association Industry Connections working group on End Effectors for Brain-Machine Interfacing that convened to identify and address gaps in the existing standards for BMI-based solutions with a focus on the end-effector component. A roadmap towards standardization of end effectors for BMI systems is discussed by identifying current device standards that are applicable for end effectors. While current standards address basic electrical and mechanical safety, and to some extent, performance requirements, several gaps exist pertaining to unified terminologies, data communication protocols, patient safety and risk mitigation.
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Affiliation(s)
| | - Justin A Brantley
- University of Houston Houston TX 77204 USA
- Department of BioengineeringUniversity of Pennsylvania Philadelphia PA 19104 USA
| | | | | | | | | | - Jesus G Cruz-Garza
- University of Houston Houston TX 77204 USA
- Department of Design and Environmental AnalysisCornell University Ithaca NY 14853 USA
| | | | | | | | - Md Rashed-Al-Mahfuz
- University of Houston Houston TX 77204 USA
- Department of Computer Science and EngineeringUniversity of Rajshahi Rajshahi 6205 Bangladesh
| | | | - Nikunj A Bhagat
- University of Houston Houston TX 77204 USA
- Feinstein Institutes for Medical Research Manhasset NY 11030 USA
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Sohn WJ, Wang PT, Kellis S, Andersen RA, Liu CY, Heydari P, Nenadic Z, Do AH. A Prototype of a Fully-Implantable Charge-Balanced Artificial Sensory Stimulator for Bi-directional Brain-Computer-Interface (BD-BCI). ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2020:3083-3085. [PMID: 33018656 DOI: 10.1109/embc44109.2020.9176718] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Bi-directional brain-computer interfaces (BD-BCI) to restore movement and sensation must achieve concurrent operation of recording and decoding of motor commands from the brain and stimulating the brain with somatosensory feedback. Previously we developed and validated a benchtop prototype of a fully implantable BCI system for motor decoding. Here, a prototype artificial sensory stimulator was integrated into the benchtop system to develop a prototype of a fully-implantable BD-BCI. The artificial sensory stimulator incorporates an active charge balancing mechanism based on pulse-width modulation to ensure safe stimulation for chronically interfaced electrodes to prevent damage to brain tissue and electrodes. The feasibility of the BD-BCI system's active charge balancing was tested in phantom brain tissue. With the charge-balancing, the removal of the residual charges on an electrode was evident. This is a critical milestone toward fully-implantable BD-BCI systems.
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Lim J, Wang PT, Shaw SJ, Armacost M, Gong H, Liu CY, Do AH, Heydari P, Nenadic Z. Pre-whitening and Null Projection as an Artifact Suppression Method for Electrocorticography Stimulation in Bi-Directional Brain Computer Interfaces. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2020:3493-3496. [PMID: 33018756 DOI: 10.1109/embc44109.2020.9175760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Electrocorticography (ECoG)-based bi-directional (BD) brain-computer interfaces (BCIs) are a forthcoming technology promising to help restore function to those with motor and sensory deficits. A major problem with this paradigm is that the cortical stimulation necessary to elicit artificial sensation creates strong electrical artifacts that can disrupt BCI operation by saturating recording amplifiers or obscuring useful neural signal. Even with state-of-the-art hardware artifact suppression methods, robust signal processing techniques are still required to suppress residual artifacts that are present at the digital back-end. Herein we demonstrate the effectiveness of a pre-whitening and null projection artifact suppression method using ECoG data recorded during a clinical neurostimulation procedure. Our method achieved a maximum artifact suppression of 21.49 dB and significantly increased the number of artifact-free frequencies in the frequency domain. This performance surpasses that of a more traditional independent component analysis methodology, while retaining a reduced complexity and increased computational efficiency.
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Pu H, Lim J, Kellis S, Liu CY, Andersen RA, Do AH, Heydari P, Nenadic Z. Optimal artifact suppression in simultaneous electrocorticography stimulation and recording for bi-directional brain-computer interface applications. J Neural Eng 2020; 17:026038. [PMID: 32208379 DOI: 10.1088/1741-2552/ab82ac] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Electrocorticogram (ECoG)-based brain-computer interfaces (BCIs) are a promising platform for the restoration of motor and sensory functions to those with neurological deficits. Such bi-directional BCI operation necessitates simultaneous ECoG recording and stimulation, which is challenging given the presence of strong stimulation artifacts. This problem is exacerbated if the BCI's analog front-end operates in an ultra-low power regime, which is a basic requirement for fully implantable medical devices. In this study, we developed a novel method for the suppression of stimulation artifacts before they reach the analog front-end. APPROACH Using elementary biophysical considerations, we devised an artifact suppression method that employs a weak auxiliary stimulation delivered between the primary stimulator and the recording grid. The exact location and amplitude of this auxiliary stimulating dipole were then found through a constrained optimization procedure. The performance of our method was tested in both simulations and phantom brain tissue experiments. MAIN RESULTS The solution found through the optimization procedure matched the optimal canceling dipole in both simulations and experiments. Artifact suppression as large as 28.7 dB and 22.9 dB were achieved in simulations and brain phantom experiments, respectively. SIGNIFICANCE We developed a simple constrained optimization-based method for finding the parameters of an auxiliary stimulating dipole that yields optimal artifact suppression. Our method suppresses stimulation artifacts before they reach the analog front-end and may prevent the front-end amplifiers from saturation. Additionally, it can be used along with other artifact mitigation techniques to further reduce stimulation artifacts.
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Affiliation(s)
- Haoran Pu
- Department of Electrical Engineering and Computer Science, University of California, Irvine, Irvine, CA, 92697, United States of America
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Caldwell DJ, Cronin JA, Rao RPN, Collins KL, Weaver KE, Ko AL, Ojemann JG, Kutz JN, Brunton BW. Signal recovery from stimulation artifacts in intracranial recordings with dictionary learning. J Neural Eng 2020; 17:026023. [PMID: 32103828 PMCID: PMC7333778 DOI: 10.1088/1741-2552/ab7a4f] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
OBJECTIVE Electrical stimulation of the human brain is commonly used for eliciting and inhibiting neural activity for clinical diagnostics, modifying abnormal neural circuit function for therapeutics, and interrogating cortical connectivity. However, recording electrical signals with concurrent stimulation results in dominant electrical artifacts that mask the neural signals of interest. Here we develop a method to reproducibly and robustly recover neural activity during concurrent stimulation. We concentrate on signal recovery across an array of electrodes without channel-wise fine-tuning of the algorithm. Our goal includes signal recovery with trains of stimulation pulses, since repeated, high-frequency pulses are often required to induce desired effects in both therapeutic and research domains. We have made all of our code and data publicly available. APPROACH We developed an algorithm that automatically detects templates of artifacts across many channels of recording, creating a dictionary of learned templates using unsupervised clustering. The artifact template that best matches each individual artifact pulse is subtracted to recover the underlying activity. To assess the success of our method, we focus on whether it extracts physiologically interpretable signals from real recordings. MAIN RESULTS We demonstrate our signal recovery approach on invasive electrophysiologic recordings from human subjects during stimulation. We show the recovery of meaningful neural signatures in both electrocorticographic (ECoG) arrays and deep brain stimulation (DBS) recordings. In addition, we compared cortical responses induced by the stimulation of primary somatosensory (S1) by natural peripheral touch, as well as motor cortex activity with and without concurrent S1 stimulation. SIGNIFICANCE Our work will enable future advances in neural engineering with simultaneous stimulation and recording.
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Affiliation(s)
- D J Caldwell
- Department of Bioengineering, University of Washington, Seattle, WA, United States of America. Medical Scientist Training Program, University of Washington, Seattle, WA, United States of America. Center for Neurotechnology, Seattle, WA, United States of America. University of Washington Institute for Neuroengineering, Seattle, WA, United States of America. Author to whom any correspondence should be addressed
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Kramer DR, Lee MB, Barbaro M, Gogia AS, Peng T, Liu C, Kellis S, Lee B. Mapping of primary somatosensory cortex of the hand area using a high-density electrocorticography grid for closed-loop brain computer interface. J Neural Eng 2020; 18. [PMID: 32131064 PMCID: PMC7483626 DOI: 10.1088/1741-2552/ab7c8e] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 03/04/2020] [Indexed: 11/11/2022]
Abstract
The ideal modality for generating sensation in sensorimotor brain computer interfaces (BCI) has not been determined. Here we report the feasibility of using a high-density "mini"-electrocorticography (mECoG) grid in a somatosensory BCI system. Thirteen subjects with intractable epilepsy underwent standard clinical implantation of subdural electrodes for the purpose of seizure localization. An additional high-density mECoG grid was placed (Adtech, 8 by 8, 1.2-mm exposed, 3-mm center-to-center spacing) over the hand area of primary somatosensory cortex. Following implantation, cortical mapping was performed with stimulation parameters of frequency: 50 Hz, pulse-width: 250 µs, pulse duration: 4 s, polarity: alternating, and current that ranged from 0.5 mA to 12 mA at the discretion of the epileptologist. Location of the evoked sensory percepts was recorded along with a description of the sensation. The hand was partitioned into 48 distinct boxes. A box was included if sensation was felt anywhere within the box. The percentage of the hand covered was 63.9% (± 34.4%) (mean ± s.d.). Mean redundancy, measured as electrode pairs stimulating the same box, was 1.9 (± 2.2) electrodes per box; and mean resolution, measured as boxes included per electrode pair stimulation, was 11.4 (± 13.7) boxes with 8.1 (± 10.7) boxes in the digits and 3.4 (± 6.0) boxes in the palm. Functional utility of the system was assessed by quantifying usable percepts. Under the strictest classification, "dermatomally exclusive" percepts, the mean was 2.8 usable percepts per grid. Allowing "perceptually unique" percepts at the same anatomical location, the mean was 5.5 usable percepts per grid. Compared to the small area of coverage and redundancy of a microelectrode system, or the poor resolution of a standard ECoG grid, a mECoG is likely the best modality for a somatosensory BCI system with good coverage of the hand and minimal redundancy.
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Affiliation(s)
- Daniel Richard Kramer
- Neurosurgery, Stanford University, 300 Pasteur Drive, Palo Alto, Stanford, California, 94305-6104, UNITED STATES
| | - Morgan Brianna Lee
- Neurosurgery, University of Southern California, Los Angeles, California, 90089-0001, UNITED STATES
| | - Michael Barbaro
- Neurosurgery, USC Keck School of Medicine, Los Angeles, California, UNITED STATES
| | - Angad S Gogia
- University of Southern California Keck School of Medicine, Los Angeles, California, 90089-9034, UNITED STATES
| | - Terrance Peng
- Neurosurgery, USC Keck School of Medicine, Los Angeles, California, UNITED STATES
| | - Charles Liu
- Neuroresotoration Center and Department of Neurosurgery and Neurology, University of Southern California, Los Angeles, California, UNITED STATES
| | - Spencer Kellis
- Neurosurgery, USC Keck School of Medicine, Los Angeles, California, UNITED STATES
| | - Brian Lee
- University of Southern California, Los Angeles, California, UNITED STATES
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Callier T, Brantly NW, Caravelli A, Bensmaia SJ. The frequency of cortical microstimulation shapes artificial touch. Proc Natl Acad Sci U S A 2020; 117:1191-1200. [PMID: 31879342 PMCID: PMC6969512 DOI: 10.1073/pnas.1916453117] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Intracortical microstimulation (ICMS) of the somatosensory cortex evokes vivid tactile sensations and can be used to convey sensory feedback from brain-controlled bionic hands. Changes in ICMS frequency lead to changes in the resulting sensation, but the discriminability of frequency has only been investigated over a narrow range of low frequencies. Furthermore, the sensory correlates of changes in ICMS frequency remain poorly understood. Specifically, it remains to be elucidated whether changes in frequency only modulate sensation magnitude-as do changes in amplitude-or whether they also modulate the quality of the sensation. To fill these gaps, we trained monkeys to discriminate the frequency of ICMS pulse trains over a wide range of frequencies (from 10 to 400 Hz). ICMS amplitude also varied across stimuli to dissociate sensation magnitude from ICMS frequency and ensure that animals could not make frequency judgments based on magnitude. We found that animals could consistently discriminate ICMS frequency up to ∼200 Hz but that the sensory correlates of frequency were highly electrode dependent: On some electrodes, changes in frequency were perceptually distinguishable from changes in amplitude-seemingly giving rise to a change in sensory quality; on others, they were not. We discuss the implications of our findings for neural coding and for brain-controlled bionic hands.
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Affiliation(s)
- Thierri Callier
- Committee on Computational Neuroscience, University of Chicago, Chicago, IL 60637
| | - Nathan W Brantly
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637
| | - Attilio Caravelli
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637
| | - Sliman J Bensmaia
- Committee on Computational Neuroscience, University of Chicago, Chicago, IL 60637;
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637
- Grossman Institute for Neuroscience, Quantitative Biology, and Human Behavior, University of Chicago, Chicago, IL 60637
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Hughes C, Herrera A, Gaunt R, Collinger J. Bidirectional brain-computer interfaces. BRAIN-COMPUTER INTERFACES 2020; 168:163-181. [DOI: 10.1016/b978-0-444-63934-9.00013-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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From thought to action: The brain-machine interface in posterior parietal cortex. Proc Natl Acad Sci U S A 2019; 116:26274-26279. [PMID: 31871144 PMCID: PMC6936686 DOI: 10.1073/pnas.1902276116] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
A dramatic example of translational monkey research is the development of neural prosthetics for assisting paralyzed patients. A neuroprosthesis consists of implanted electrodes that can record the intended movement of a paralyzed part of the body, a computer algorithm that decodes the intended movement, and an assistive device such as a robot limb or computer that is controlled by these intended movement signals. This type of neuroprosthetic system is also referred to as a brain-machine interface (BMI) since it interfaces the brain with an external machine. In this review, we will concentrate on BMIs in which microelectrode recording arrays are implanted in the posterior parietal cortex (PPC), a high-level cortical area in both humans and monkeys that represents intentions to move. This review will first discuss the basic science research performed in healthy monkeys that established PPC as a good source of intention signals. Next, it will describe the first PPC implants in human patients with tetraplegia from spinal cord injury. From these patients the goals of movements could be quickly decoded, and the rich number of action variables found in PPC indicates that it is an appropriate BMI site for a very wide range of neuroprosthetic applications. We will discuss research on learning to use BMIs in monkeys and humans and the advances that are still needed, requiring both monkey and human research to enable BMIs to be readily available in the clinic.
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Abstract
This report discusses how a number of currently incurable diseases might be treated by advances developed as the result of current ongoing research on monkeys. The diseases discussed include Parkinson's disease, amyotrophic lateral sclerosis, spinal cord injury, peripheral neuropathy, and stroke. Finally, the report discusses the devastating effect the animal rights movement and adverse publicity can have on basic neurobiological research on monkeys.
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Sombeck JT, Miller LE. Short reaction times in response to multi-electrode intracortical microstimulation may provide a basis for rapid movement-related feedback. J Neural Eng 2019; 17:016013. [PMID: 31778982 PMCID: PMC7189902 DOI: 10.1088/1741-2552/ab5cf3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
OBJECTIVE Tetraplegic patients using brain-machine interfaces can make visually guided reaches with robotic arms. However, restoring proprioceptive feedback to these patients will be critical, as evidenced by the movement deficit in patients with proprioceptive loss. Proprioception is critical in large part because it provides faster feedback than vision. Intracortical microstimulation (ICMS) is a promising approach, but the ICMS-evoked reaction time (RT) is typically slower than that to natural proprioceptive and often even visual cues, implying that ICMS feedback may not be fast enough to guide movement. APPROACH For most sensory modalities, RT decreases with increased stimulus intensity. Thus, it may be that stimulation intensities beyond what has previously been used will result in faster RTs. To test this, we compared the RT to ICMS applied through multi-electrode arrays in area 2 of somatosensory cortex to that of mechanical and visual cues. MAIN RESULTS We found that the RT to single-electrode ICMS decreased with increased current, frequency, and train length. For 100 µA, 330 Hz stimulation, the highest single-electrode intensity we tested routinely, most electrodes resulted in RTs slower than the mechanical cue but slightly faster than the visual cue. While increasing the current beyond 100 µA resulted in faster RTs, sustained stimulation at this level may damage tissue. Alternatively, by stimulating through multiple electrodes (mICMS), a large amount of current can be injected while keeping that through each electrode at a safe level. We found that stimulation with at least 480 µA equally distributed over 16 electrodes could produce RTs as much as 20 ms faster than the mechanical cue, roughly the conduction delay to cortex from the periphery. SIGNIFICANCE These results suggest that mICMS may provide a means to supply rapid, movement-related feedback. Future neuroprosthetics may need spatiotemporally patterned mICMS to convey useful somatosensory information. Novelty & Significance Intracortical microstimulation (ICMS) is a promising approach for providing artificial somatosensation to patients with spinal cord injury or limb amputation, but in prior experiments, subjects have been unable to respond as quickly to it as to natural cues. We have investigated the use of multi-electrode stimulation (mICMS) and discovered that it can produce reaction times as fast or faster even than natural mechanical cues. Although our stimulus trains were not modulated in time, this result opens the door to more complex spatiotemporal patterns of mICMS that might be used to rapidly write in complex somatosensory information to the CNS.
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Affiliation(s)
- Joseph T Sombeck
- Department of Physiology, Northwestern University, Chicago, IL, United States of America. Department of Biomedical Engineering, Northwestern University, Evanston, IL, United States of America
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38
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Kramer DR, Lamorie-Foote K, Barbaro M, Lee M, Peng T, Gogia A, Liu CY, Kellis SS, Lee B. Functional Frequency Discrimination From Cortical Somatosensory Stimulation in Humans. Front Neurosci 2019; 13:832. [PMID: 31440133 PMCID: PMC6692717 DOI: 10.3389/fnins.2019.00832] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 07/25/2019] [Indexed: 01/14/2023] Open
Abstract
Recently, efforts to produce artificial sensation through cortical stimulation of primary somatosensory cortex (PSC) in humans have proven safe and reliable. Changes in stimulation parameters like frequency and amplitude have been shown to elicit different percepts, but without clearly defined psychometric profiles. This study investigates the functionally useful limits of frequency changes on the percepts felt by three epilepsy patients with subdural electrocorticography (ECoG) grids. Subjects performing a hidden target task were stimulated with parameters of constant amplitude, pulse-width, and pulse-duration, and a randomly selected set of two frequencies (20, 30, 40, 50, 60, and 100 Hz). They were asked to decide which target had the “higher” frequency. Objectively, an increase in frequency differences was associated with an increase in perceived intensity. Reliable detection of stimulation occurred at and above 40 Hz with a lower limit of detection around 20 Hz and a just-noticeable difference estimated at less than 10 Hz. These findings suggest that frequency can be used as a reliable, adjustable parameter and may be useful in establishing settings and thresholds of functionality in future BCI systems.
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Affiliation(s)
- Daniel R Kramer
- Department of Neurosurgery, University of Southern California, Los Angeles, CA, United States.,Neurorestoration Center, University of Southern California, Los Angeles, CA, United States
| | - Krista Lamorie-Foote
- Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Michael Barbaro
- Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Morgan Lee
- Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Terrance Peng
- Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Angad Gogia
- Keck School of Medicine, University of Southern California, Los Angeles, CA, United States
| | - Charles Y Liu
- Department of Neurosurgery, University of Southern California, Los Angeles, CA, United States.,Neurorestoration Center, University of Southern California, Los Angeles, CA, United States
| | - Spencer S Kellis
- Neurorestoration Center, University of Southern California, Los Angeles, CA, United States.,Department of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States.,Tianqiao and Chrissy Chen Brain-Machine Interface Center, California Institute of Technology, Pasadena, CA, United States
| | - Brian Lee
- Department of Neurosurgery, University of Southern California, Los Angeles, CA, United States.,Neurorestoration Center, University of Southern California, Los Angeles, CA, United States
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Caldwell DJ, Ojemann JG, Rao RPN. Direct Electrical Stimulation in Electrocorticographic Brain-Computer Interfaces: Enabling Technologies for Input to Cortex. Front Neurosci 2019; 13:804. [PMID: 31440127 PMCID: PMC6692891 DOI: 10.3389/fnins.2019.00804] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 07/18/2019] [Indexed: 12/22/2022] Open
Abstract
Electrocorticographic brain computer interfaces (ECoG-BCIs) offer tremendous opportunities for restoring function in individuals suffering from neurological damage and for advancing basic neuroscience knowledge. ECoG electrodes are already commonly used clinically for monitoring epilepsy and have greater spatial specificity in recording neuronal activity than techniques such as electroencephalography (EEG). Much work to date in the field has focused on using ECoG signals recorded from cortex as control outputs for driving end effectors. An equally important but less explored application of an ECoG-BCI is directing input into cortex using ECoG electrodes for direct electrical stimulation (DES). Combining DES with ECoG recording enables a truly bidirectional BCI, where information is both read from and written to the brain. We discuss the advantages and opportunities, as well as the barriers and challenges presented by using DES in an ECoG-BCI. In this article, we review ECoG electrodes, the physics and physiology of DES, and the use of electrical stimulation of the brain for the clinical treatment of disorders such as epilepsy and Parkinson’s disease. We briefly discuss some of the translational, regulatory, financial, and ethical concerns regarding ECoG-BCIs. Next, we describe the use of ECoG-based DES for providing sensory feedback and for probing and modifying cortical connectivity. We explore future directions, which may draw on invasive animal studies with penetrating and surface electrodes as well as non-invasive stimulation methods such as transcranial magnetic stimulation (TMS). We conclude by describing enabling technologies, such as smaller ECoG electrodes for more precise targeting of cortical areas, signal processing strategies for simultaneous stimulation and recording, and computational modeling and algorithms for tailoring stimulation to each individual brain.
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Affiliation(s)
- David J Caldwell
- Department of Bioengineering, University of Washington, Seattle, WA, United States.,Medical Scientist Training Program, University of Washington, Seattle, WA, United States.,Center for Neurotechnology, University of Washington, Seattle, WA, United States
| | - Jeffrey G Ojemann
- Center for Neurotechnology, University of Washington, Seattle, WA, United States.,Department of Neurological Surgery, University of Washington, Seattle, WA, United States
| | - Rajesh P N Rao
- Department of Bioengineering, University of Washington, Seattle, WA, United States.,Center for Neurotechnology, University of Washington, Seattle, WA, United States.,Paul G. Allen School of Computer Science and Engineering, University of Washington, Seattle, WA, United States
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Lee MB, Kramer DR, Peng T, Barbaro MF, Liu CY, Kellis S, Lee B. Clinical neuroprosthetics: Today and tomorrow. J Clin Neurosci 2019; 68:13-19. [PMID: 31375306 DOI: 10.1016/j.jocn.2019.07.056] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 06/27/2019] [Accepted: 07/16/2019] [Indexed: 12/19/2022]
Abstract
Implantable neurostimulation devices provide a direct therapeutic link to the nervous system and can be considered brain-computer interfaces (BCI). Under this definition, BCI are not simply science fiction, they are part of existing neurosurgical practice. Clinical BCI are standard of care for historically difficult to treat neurological disorders. These systems target the central and peripheral nervous system and include Vagus Nerve Stimulation, Responsive Neurostimulation, and Deep Brain Stimulation. Recent advances in clinical BCI have focused on creating "closed-loop" systems. These systems rely on biomarker feedback and promise individualized therapy with optimal stimulation delivery and minimal side effects. Success of clinical BCI has paralleled research efforts to create BCI that restore upper extremity motor and sensory function to patients. Efforts to develop closed loop motor/sensory BCI is linked to the successes of today's clinical BCI.
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Affiliation(s)
- Morgan B Lee
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA; USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, CA, USA.
| | - Daniel R Kramer
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA; USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, CA, USA
| | - Terrance Peng
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA; USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, CA, USA
| | - Michael F Barbaro
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA; USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, CA, USA
| | - Charles Y Liu
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA; USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, CA, USA; Department of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Spencer Kellis
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA; USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, CA, USA; T&C Chen Brain Machine Interface Center, California Institute of Technology, Pasadena, CA, USA; Department of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Brian Lee
- Department of Neurological Surgery, Keck School of Medicine of USC, University of Southern California, Los Angeles, CA, USA; USC Neurorestoration Center, Keck School of Medicine of USC, Los Angeles, CA, USA; Department of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
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Lee MB, Kramer DR, Peng T, Barbaro MF, Liu CY, Kellis S, Lee B. Brain-Computer Interfaces in Quadriplegic Patients. Neurosurg Clin N Am 2019; 30:275-281. [DOI: 10.1016/j.nec.2018.12.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Caldwell DJ, Cronin JA, Wu J, Weaver KE, Ko AL, Rao RPN, Ojemann JG. Direct stimulation of somatosensory cortex results in slower reaction times compared to peripheral touch in humans. Sci Rep 2019; 9:3292. [PMID: 30824821 PMCID: PMC6397274 DOI: 10.1038/s41598-019-38619-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 01/04/2019] [Indexed: 01/13/2023] Open
Abstract
Direct cortical stimulation (DCS) of primary somatosensory cortex (S1) could help restore sensation and provide task-relevant feedback in a neuroprosthesis. However, the psychophysics of S1 DCS is poorly studied, including any comparison to cutaneous haptic stimulation. We compare the response times to DCS of human hand somatosensory cortex through electrocorticographic grids with response times to haptic stimuli delivered to the hand in four subjects. We found that subjects respond significantly slower to S1 DCS than to natural, haptic stimuli for a range of DCS train durations. Median response times for haptic stimulation varied from 198 ms to 313 ms, while median responses to reliably perceived DCS ranged from 254 ms for one subject, all the way to 528 ms for another. We discern no significant impact of learning or habituation through the analysis of blocked trials, and find no significant impact of cortical stimulation train duration on response times. Our results provide a realistic set of expectations for latencies with somatosensory DCS feedback for future neuroprosthetic applications and motivate the study of neural mechanisms underlying human perception of somatosensation via DCS.
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Affiliation(s)
- David J Caldwell
- Department of Bioengineering, University of Washington, Seattle, USA. .,Medical Scientist Training Program, University of Washington, Seattle, USA. .,National Science Foundation Center for Neurotechnology, Seattle, USA.
| | - Jeneva A Cronin
- Department of Bioengineering, University of Washington, Seattle, USA. .,National Science Foundation Center for Neurotechnology, Seattle, USA.
| | - Jing Wu
- Department of Bioengineering, University of Washington, Seattle, USA.,National Science Foundation Center for Neurotechnology, Seattle, USA
| | - Kurt E Weaver
- Department of Radiology, University of Washington, Seattle, USA.,National Science Foundation Center for Neurotechnology, Seattle, USA
| | - Andrew L Ko
- Department of Neurological Surgery, University of Washington, Seattle, USA.,National Science Foundation Center for Neurotechnology, Seattle, USA
| | - Rajesh P N Rao
- Department of Computer Science and Engineering, University of Washington, Seattle, USA.,National Science Foundation Center for Neurotechnology, Seattle, USA
| | - Jeffrey G Ojemann
- Department of Neurological Surgery, University of Washington, Seattle, USA.,National Science Foundation Center for Neurotechnology, Seattle, USA
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Electrocorticographic changes in field potentials following natural somatosensory percepts in humans. Exp Brain Res 2019; 237:1155-1167. [PMID: 30796470 DOI: 10.1007/s00221-019-05495-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 02/15/2019] [Indexed: 01/06/2023]
Abstract
OBJECTIVE Restoration of somatosensory deficits in humans requires a clear understanding of the neural representations of percepts. To characterize the cortical response to naturalistic somatosensation, we examined field potentials in the primary somatosensory cortex of humans. METHODS Four patients with intractable epilepsy were implanted with subdural electrocorticography (ECoG) electrodes over the hand area of S1. Three types of stimuli were applied, soft-repetitive touch, light touch, and deep touch. Power in the alpha (8-15 Hz), beta (15-30 Hz), low-gamma (30-50 Hz), and high-gamma (50-125 Hz) frequency bands were evaluated for significance. RESULTS Seventy-seven percent of electrodes over the hand area of somatosensory cortex exhibited changes in these bands. High-gamma band power increased for all stimuli, with concurrent alpha and beta band power decreases. Earlier activity was seen in these bands in deep touch and light touch compared to soft touch. CONCLUSIONS These findings are consistent with prior literature and suggest a widespread response to focal touch, and a different encoding of deeper pressure touch than soft touch.
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Kramer DR, Kellis S, Barbaro M, Salas MA, Nune G, Liu CY, Andersen RA, Lee B. Technical considerations for generating somatosensation via cortical stimulation in a closed-loop sensory/motor brain-computer interface system in humans. J Clin Neurosci 2019; 63:116-121. [PMID: 30711286 DOI: 10.1016/j.jocn.2019.01.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 01/04/2019] [Accepted: 01/18/2019] [Indexed: 10/27/2022]
Abstract
Somatosensory feedback is the next step in brain computer interface (BCI). Here, we compare three cortical stimulating array modalities for generating somatosensory percepts in BCI. We compared human subjects with either a 64-channel "mini"-electrocorticography grid (mECoG; 1.2-mm diameter exposed contacts with 3-mm spacing, N = 1) over the hand area of primary somatosensory cortex (S1), or a standard grid (sECoG; 1.5-mm diameter exposed contacts with 1-cm spacing, N = 1), to generate artificial somatosensation through direct electrical cortical stimulation. Finally, we reference data in the literature from a patient implanted with microelectrode arrays (MEA) placed in the S1 hand area. We compare stimulation results to assess coverage and specificity of the artificial percepts in the hand. Using the mECoG array, hand mapping revealed coverage of 41.7% of the hand area versus 100% for the sECoG array, and 18.8% for the MEA. On average, stimulation of a single electrode corresponded to sensation reported in 4.42 boxes (range 1-11 boxes) for the mECoG array, 19.11 boxes (range 4-48 boxes) for the sECoG grid, and 2.3 boxes (range 1-5 boxes) for the MEA. Sensation in any box, on average, corresponded to stimulation from 2.65 electrodes (range 1-5 electrodes) for the mECoG grid, 3.58 electrodes for the sECoG grid (range 2-4 electrodes), and 11.22 electrodes (range 2-17 electrodes) for the MEA. Based on these findings, we conclude that mECoG grids provide an excellent balance between spatial cortical coverage of the hand area of S1 and high-density resolution.
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Affiliation(s)
- Daniel R Kramer
- Department of Neurosurgery, University of Southern California, Los Angeles, CA, USA.
| | - Spencer Kellis
- Department of Neurosurgery, University of Southern California, Los Angeles, CA, USA; Department of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA; Tianqiao and Chrissy Chen Brain-machine Interface Center, California Institute of Technology, Pasadena, CA, USA
| | - Michael Barbaro
- Department of Neurosurgery, University of Southern California, Los Angeles, CA, USA
| | - Michelle Armenta Salas
- Department of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA; Tianqiao and Chrissy Chen Brain-machine Interface Center, California Institute of Technology, Pasadena, CA, USA
| | - George Nune
- Department of Neurology, University of Southern California, Los Angeles, CA, USA
| | - Charles Y Liu
- Department of Neurosurgery, University of Southern California, Los Angeles, CA, USA; Department of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Richard A Andersen
- Department of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA; Tianqiao and Chrissy Chen Brain-machine Interface Center, California Institute of Technology, Pasadena, CA, USA
| | - Brian Lee
- Department of Neurosurgery, University of Southern California, Los Angeles, CA, USA; Department of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
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