|Center for Devices & Radiological Health, FDA||USA|
Session 1: Vision prosthetics 9:40-10:55
|Univ. New South Wales||Australia|
|Seoul National University||Korea|
|Illinois Institute of Technology & Sigenics||USA|
Coffee/Tea Break 10:55-11:10
Session 2: Signal processing and power telemetry in neuroprosthetics 11:10-12:00
|UC Santa Cruz & National University of Singapore||USA & Singapore|
Session 3: Vestibular prosthetics 13:00-14:10
|University of Newcastle||Australia|
|John Hopkins University||USA|
|Univ. New South Wales||Australia||Panel discussion on vestibular prosthetics|
Coffee/Tea Break 14:10-14:40
Session 4: Neuromodulation for Parkinson’s disease, epilepsy, hyperreflexia, chronic pain 14:40-16:40
|National Chiao Tung University||Taiwan|
|University College London||UK|
|NICTA & UNSW||Australia|
Saturday, 26 November 2011
Session 5: Neuroprosthetic electrodes 9:00-9:50
|Huntington Medical Research Institutes||USA|
Group Photo and Coffee/Tea Break 9:50-10:30
Session 6: Electrical stimulation and drug delivery for hearing 10:30-12:00
|Gary Housley, PhD||University of New South Wales||Australia||Discussion|
Session 7: Poster Session 13:00-14:00
Session 8: Prosthetics for muscle paralysis 14:00-16:30
|University of Sydney||Australia|
|Michigan State University||USA|
|Florida International University||USA|
Center for Devices and Radiological Health, FDA
Silver Spring, MD, USA
Dr. Cohen received his Ph.D. in the vision research lab of Dr. Peter Sterling at the University of Pennsylvania Medical School in 1987.
After postdoctoral physiology training at the University of Minnesota with Dr. Robert Miller, and at the Jules Stein Eye Inst of UCLA with Gordon Fain, he joined the faculty in the Dept of Ophthalmology and Visual Science at Yale University Medical School as a retinal physiologist in 1992.
In 2000, he was a visiting professor in the Dept. of Molecular and Cellular Biology at Harvard University. Since 2003, he is a Research Scientist in the FDA Office of Science and Engineering Labs in the Center for Devices and Radiological Health. Dr. Cohen’s research studies have included mammalian retinal microcircuitry, NEURON modeling of ganglion cell firing mechanisms, light-evoked synaptic currents of mammalian retinal ganglion cells, multi-unit recording arrays, and primate retinal pharmacology.
Dr. Cohen is presently working on developing novel methods for optimizing and imaging stimulation of neuronal tissue by neural prostheses.
Ethan D. Cohen
Office of Science and Engineering Labs
Center for Devices and Radiological Health, FDA
Retinal prostheses for the blind are currently undergoing clinical trials worldwide in humans. However, there is limited data about what are safe and unsafe levels of electrical stimulation for the retina.
A difficulty for real-time in-vivo evaluation is because most stimulus electrodes, particularly epiretinal designs, are made of opaque metals/oxides that block visual inspection of the underlying retina, where the highest electric-fields are thought to be developed.
Examination of retinal damage by histological methods allows sampling only of single time points, and the tissue can be distorted by processing. It is difficult to examine the physiological state of the retina under the stimulus electrode, particularly after overstimulation.
We have developed a novel method to study the effects of electrical stimulation of the local retina directly under a stimulus electrode in real time by using an optically transparent fluopolymer salt-bridge electrode. Using a retinal eyecup preparation, we originally examined the light-evoked firing of ganglion cells directly under these transparent stimulus electrodes before and after high charge density pulse train stimulation.
After high pulse train stimulation at 50Hz, the light-evoked firing of ganglion cells was depressed and took many minutes to recover. Using our transparent electrode, we have developed a new optical coherence tomography (OCT) method to image how the retinal layers are affected by pulse train stimulation in real-time.
These studies have revealed that the high-level pulse charge densities that previously caused ganglion cell firing depression appear to cause significant retinal swelling and long term increases in retinal reflectivity suggestive of damage.
A significant component of the current and damage may be carried by the Müller glial cells. Our transparent tube OCT imaging method may be useful for analyzing the status of neuronal tissue under stimulation electrodes in many different brain regions.
Head, Dept. of Ophthalmology
Dr. Sachs received his MD at the Institute for Medical Psychology of Ludwig-Maximilians-Universität. He completed his Residency in Ophthalmology at the University of Regensburg with Prof. V-P. Gabel were he became commissionary Director of the University Eye Clinic in Regensburg in 2006.
Since 2008, he is heading the Dept. of Ophthalmology at Dresden-Friedrichstadt Clinic, a teaching hospital of the Technical University in Dresden.
Dr. Sachs devoted most of his scientific activities to retinal prosthesis development in the German Subretinal Implant Project, which was coordinated by Prof. Zrenner from Tuebingen. During his research work in Regensburg he developed the transchoroidal implantation technique in various animal models and transferred the technique from the laboratory setting to the clinic. He was the first to carry out implantations via this new approach in patients.
His particular interests and clinical involvement include vitreoretinal surgery age related macular degeneration and macular pathologies.
A surgeon’s experience and view to different possible approaches
Helmut G. Sachs
Dresden-Friedrichstadt Clinic, Germany
Various research groups were developing visual prostheses worldwide since the 1990s. Different surgical approaches are under investigation. The functional results achieved with these devices suggest that vision can be restored to some extent. Blindness by retinal degeneration is the target of most of the research groups.
Using different surgical attempts and implantation strategies visual prostheses have been placed in laboratory investigations (animal experiments) and later in clinical trials over the past years.
Promising visual results were demonstrated by a few groups using epiretinal and subretinal placed stimulation devices. Stimulation zones other than the retina are under investigation as well. Taken into consideration that the knowledge about the organisation of the visual system is limited the retina with its acceptable surgical accessibility is consequently one of the main targets in clinical research.
Despite encouraging results in a limited number of patients a lot of questions emerged with the implants delivering more and better results. The visual experience of the patients suggests that single stimulation electrodes do not act independently like a single pixel. Hence the visual percept evoked by the devices in use is in its complexity by far from being completely understood.
However the results of our common efforts in this scene let us begin to understand the interaction between stimulating parameters and visual percepts. The visual percept triggered by the stimulation with the devices in blind patients is difficult to predict – an enormous challenge for the researchers in this field.
To put the researchers into the position to achieve interpretable results surgery plays the major role. This surgical problem (retinal surgery) is by far not trivial. Our capability to understand the interaction in the visual system at that stage of the perceptual process is directly linked to the surgical success or the appropriate surgical implantation strategy.
The goal must be to place the implant and thus the stimulating electrode carefully in the proximity of the targeted cell population. This does not necessarily mean that this desired stimulation condition is stable in the long run especially in the unique anatomical situation of the retina.
This is one of the most challenging aspects of retinal surgery overall. Researchers have to understand the principles and the limitations of retinal or eye surgery to build structures that will be long-term successful stimulation devices. Surgical key aspects that we learned over the past years are addressed in this presentation.
Associate Professor of Biomedical Engineering
University of New South Wales
Gregg J. Suaning has over two decades of experience in implantable neuroprostheses in both industry and academia. He received his Bachelor and Master of Science degrees from the California State University in 1986 and 1988 respectively.
Since 1992, he has been conducting industrial research into neural prosthetics with Nucleus CI24 cochlear implant for the deaf. Since 1997, he has been pioneering Australia’s research efforts in visual neuroprosthetics for the blind with the Australian Vision Prosthesis Group (AVPG) which he co-founded and co-leads.
His Ph.D. in visual prosthesis from the University of New South Wales (UNSW), Sydney, Australia was awarded in 2003. He is a prolific inventor with several patents in the medical device field and has authored over 100 book chapters, refereed journal manuscripts and conference proceedings.
He holds a Conjoint Associate Professorship in the School of Engineering at the University of Newcastle, and has been a Visiting Scientist at the University of Freiburg, Germany, and Aalborg University, Denmark. His primary research is in implantable sensory neuroprostheses along with a number of projects in movement disorders and medical diagnostics.
Gregg J. Suaning
University of New South Wales, Sydney, Australia
Intervention using surgically-implanted neuroprostheses for the treatment of blindness can be applied at a number of sites along the visual pathway. The choice of site of intervention is made through consideration of several factors including neuron survival, stimulation efficacy, biostability, and surgical accessibility.
Retinitis Pigmentosa (RP) is one of a handful of diseases that can lead to profound blindness yet leave important neural elements of the visual pathway largely in-tact and capable of producing physiological events through electrical neurostimulation. This can lead to the psychophysical perception of a point of light or phosphene .
A mosaic of phosphenes can be used to produce patterned vision. In RP, the survival (at least in part) of the retinal ganglion cell (RGC) layer of the retina, the axons of which collectively form the optic nerve, provides an opportunity to deliver electrical stimuli to the neural retina in order to restore rudimentary pattern vision.
Within the eye, three key sites of intervention using neuroprosthesis are being explored:
• the epi-retinal surface where the RGCs and their axons can be in close proximity to stimulating electrodes;
• the sub-retinal space (between the photoreceptor layer and the retinal pigment epithelium) where stimulation of additional, surviving elements of the visual pathway (e.g. bipolar cells) may provide benefit through retinal pre-processing; and,
• the supra-choroidal space (between the sclera and choroid) where surgical accessibility is simplified, and biostability benefits may exist by separating the stimulating electrodes from the targeted neural elements.
The presenter’s research team has explored the electrical stimulation of the retina and has chosen the supra-choroidal space as the site of intervention in their pursuit of a clinically useful visual prosthesis for the blind.
The presentation will explore the benefits and possible pitfalls of each of the approaches in applied electrical stimulation of the retina, and highlight the progress made so far in the engineering and implementation of a supra-choroidal neurostimulator.
Retina Specialist, Dept. of Ophthalmology
Professor, Dept. of Electrical Engineering
Seoul National University
Seoul, South Korea
Dr. Seo received his MD, and MS and PhD degrees in biomedical engineering from Seoul National University (SNU) in 1996, 2002 and 2005, respectively. He was trained at the department of ophthalmology of SNU Hospital as a retina specialist at the Seoul Artificial Retina Project, the dept. of ophthalmology at SNU Hospital.
Since 2008, He also teaches at the dept. of electrical engineering of SNU. His research interests are vision prosthesis, Bio-MEMS, neural stem cells, medical image processing, medical informatics and hospital information systems.
Jong-Mo Seo1,2, Kyung Hwan Kim3, Yong Sook Goo4, Kwang Suk Park5, Gregg J. Suaning6, Nigel Lovell6, Dong-Il Cho1, Sung June Kim1, Hum Chung2
1Electrical Engineering, 2Ophthalmology, 5Biomedical Engineering, Seoul National University
3Biomedical Engineering, Yonsei University
4Physiology, Chungbuk National University
6Biomedical Engineering, University of New South Wales
Seoul artificial retina project is aimed at restoring vision by electrical retinal stimulation, via collaboration with Australian Vision Prosthesis Group. Polyimide, polyimide/silicone, silicone and liquid crystal polymer-based microelectrode arrays were developed, and the surgical techniques for epiretinal, subretinal and suprachoroidal stimulation were investigated.
In vitro and in vivo biocompatibility and stability were evaluated, and in vivo functioning was tested by evoked potential analysis and positron emission tomography.
Electrical stimulation, signal encoding and decoding were studied on the basis of the in vitro intraretinal neural network analysis of the degenerated retina. Even though there are several challenges and hurdles for the successful development of retinal prosthesis, we believe that most of these can be overcome in the near future.
This project is supported by Korea Health 21 R&D Project A050251 of MIHWAF, Technology Innovation Program 10033634 of MKE, Public Welfare & Safety R&D Project 2010-0020847 and Basic Research Program 2011-0027325 of MEST.
Director of Laboratory for Neural Prosthetic Research
Associate Professor of Biomedical Engineering
Illinois Institute of Technology, Chicago, IL, USA
President, Sigenics, Inc, Chicago, IL, USA
Dr. Troyk received his MS and PhD degrees in Bioengineering from the University of Illinois, in 1980 and 1983. Until 1994, he worked as an engineer at the Northrop Corporation. Since 1983, he was an Assistant and then Associate Professor at the Department of Electrical and Computer Engineering at IIT.
In 2000, he founded and became a president of Sigenics, Inc. Since 2001, he is a Director of Neural Engineering, CINNR, and Laboratory of Neural Prosthetic Research at IIT.
His research interests include: neural interface technologies for neuroprosthetics and orthotics; visual prostheses; central and peripheral nervous system prostheses; packaging of electronics for biological implantation; and design of application-specific integrated circuits.
Philip R. Troyk, PhD
Associate Professor, Biomedical Engineering
Illinois Institute of Technology, Chicago, IL
President, Sigenics, Inc., Chicago, IL
Decades of research have been directed towards the clinical testing of an intracortical visual prosthesis. The intracortical approach is attractive because a large percentage of those individuals with blindness may not be candidates for a retinal or optic nerve visual prosthesis.
The intracortical approach is unattractive because the visual map available at the primary visual cortex is significantly less regular than that at the retina. Therefore, the appropriate encoding of artificial visual information for direct communication with the cortex is uncertain.
Despite this lack of predictability, the intracortical approach remains attractive owing to the possibility of utilizing higher-order visual features.
Our research has culminated in maturation of the hardware necessary to implement an experimental visual prosthesis in a human volunteer. We estimate that approximately 1000 electrodes could be implanted in a dorso-lateral location of the occipital pole. Mapping derived from empirical studies suggests that up to 40 degrees of eccentricity could be obtained for spatial percepts.
It is unknown whether these phosphenes could be integrated into useful visual sensory perception. However, extensive psychological studies of former and potential visual prosthesis recipients give us confidence that an appropriate cost-benefit ratio exists for recruitment and participation of a human volunteer in a clinical trial.
Our system consists of wireless 16-electrode stimulator modules capable of bidirectional telemetry and electrical stimulation specific to activated iridium oxide electrodes. Presently we are formulating the roadmap towards a clinical trial.
|Dept. Electrical Engineering||Dept El. & Computer Eng.|
|UC Santa Cruz||Nat’l University of Singapore|
|Wentai Liu received a B.S. degree from National Chiao-Tung University in Taiwan, a M.S. degree from National Taiwan University, and a Ph.D. from the University of Michigan. In 1983, he joined North Carolina State University, where he held the Alcoa Chair Professorship in electrical and computer engineering and was the founder of the Analog/Mixed-Mode Design Consortium.
Since 2003, he has been a professor in the electrical engineering at UCSC. His research interests include neuroengineering, invasive and non-invasive neural prosthesis, brain-machine interface, bioelectronics, transceiver, sensors and actuators, timing/clock optimization, computer vision/image processing.
Since its early stages, he has been leading the engineering efforts of the retinal prosthesis to restore vision, which was successful implanted in blind patients.
|Dr. Zhi received a B.S. degree from Zhejiang University in China in 2004, and a M.S. degree and a Ph.D. degree from University of California at Santa Cruz in 2007 and 2010, respectively.
At UCSC, he led the design, realization and optimization of a 256-channel epiretinal implant chip consisting of power telemetry delivering 100mW at 10-20mm separation with 10-25% efficiency, and data telemetry providing 2Mbps forward
date rate, digital controllers, and 256-channel high voltage stimulator.
His current research includes neural interfaces, neural computation, artificial cognitive systems, and integrated electronics. He has published more than 30 technical papers in the past five years.
|He also holds a Chair Professorship at National Chiao-Tung University. He has published more than 250 technical papers. He received 2009 R&D-100 Editor Choice Award, 2010 Popular Mechanics Breakthrough Invention Award.
He serves as an associate or guest editors for multiple IEEE journals. He is also an ISSCC Committee member. He is a co-founder of the International Conference on Neuroprosthetic Devices (ICNPD).
Wentai Liu, PhD & Zhi Yang, PhD
UC Santa Cruz & National Univ. Singapore
Research in neuro-prosthetic systems has progressed rapidly in the recent years fueled by the unique interdisciplinary efforts fusing engineering, medicine, and biology. However elegant solutions are needed for the major enabling technology including biological recording, stimulation, bio-signal processing, wireless communication, sensing, electrode, hermetic packaging, and powering, where the implants must deal with critical constraints of size, power, reliability, safety, and technology.
The additional heterogeneous system testing/measurements under the regulatory and compliance guidelines critically differentiate from the conventional electronic system designs and accordingly require new design methodology at every design level.
Clearly, integration and miniaturization of the implants become very essential and require solutions from many fronts – device, circuit, architecture, system, algorithm, design, testing, packaging, and technology.
This talk will first define the enabling technologies and then present the challenges/progress to realize integrated and miniaturized neural implants in the content of the major functional blocks such as recording, stimulation, signal processing, powering, and bi-direction wireless communication.
These enabling technologies need new insights, formulations, and approaches beyond just device material and circuit techniques. As an example, we will demonstrate that the fundamental understanding of the neural signal/noise characteristics could lead to a better way of optimizing the design of the recording functions and thus improving the performance of the neural data acquisition and processing/decision modules.
This new discovery greatly facilitates the implementation of a better performance high density recording system which will be presented in the talk.
Director, Institute of Man-Machine & Medical Engineering
Professor, Tsinghua University
Luming Li was born in Shandong, China in 1968. He received the B.S degree in Mechanical Engineering and the M.S. and Ph.D degrees in Material Science and Engineering from Tsinghua University, Beijing, China, in 1996. After that, he worked as an assistant professor at the Department of Mechanical Engineering at Tsinghua University.
Dr. Li became associate and full professor in 1998 and 2003, respectively. He moved to the Aerospace School at the same university in 2005, where he is currently the director and professor of the Institute of Man-Machine and Medical Engineering.
Dr. Li is also a vice chairman of the Chinese Society of Neuromodulation. His research interests include neuromodulation technology and implantable neuroprostheses.
The lifetime of a deep brain stimulation (DBS) device is most important factor for the patients who submit to DBS therapy, particularly in developing countries. Therefore, using a rechargeable rather than disposable battery provides a valuable and practical solution. In fact, rechargeable neuromodulation devices have been in clinical use for a long time, e.g. for pain control.
The issue of tissue heating during device’s wireless charging is of major concern, and only a limited number of research papers have addressed it.
In this talk, I will report on the rechargeable DBS device that has been designed and fabricated at Tsinhgua University as a modification of our battery-powered DBS device. The power transfer strategy is the key element to our design. Simulation of optimized magnetic coupling was carried out in our lab for the past several years, including the influence of antenna coupling, frequency, efficiency, distance, and positioning.
The initial evaluation was done using pork meat placed in a temperature-controlled chamber, and subsequent experiment involved implanting the rechargeable devices were in animals (pigs were chosen because of their skin thickness). \
While the devices were wirelessly recharged, we monitored the internal device temperature (at the coil and battery) and also in the pig tissue above and below the device, using the optical thermal sensors.
Associate Professor in the School of Biomedical Sciences
University of Newcastle
Dr. Brichta is a neurobiologist with research interests in the anatomy and physiology of peripheral and central vestibular system. In particular his studies have focused on hair cells, primary afferents. He has recently developed a preparation of the isolated inner ear.
This approach allows stable, high-resolution, intracellular recordings whilst the tissue undergoes near ‘natural’ (mechanical), rather than artificial (electrical) stimulation. Results from these studies are helping us understand the cellular mechanisms underlying normal and abnormal function associated with the peripheral vestibular apparatus.
Alan M. Brichta
University of Newcastle, Australia
The balance (vestibular) system is a vital, perhaps under-appreciated, sensory system that impacts most, if not all, central nervous system (CNS) functions. Obvious targets of vestibular influence are posture maintenance, movement control, and vision stabilization. However, balance information also significantly affects hearing, general sensation, and even complex processes such as learning and memory. Indeed, it is only when a disturbed vestibular system interrupts our everyday activities by causing dizziness, vertigo, and imbalance are we physically aware of its ubiquitous role in normal function.
It is now 40 years since Fernandez and Goldberg (1971) published their landmark studies that described balance signals in non-human primates in response to head rotations and tilts. These studies provided the first real insights into the surprisingly complex signals generated by the inner ear and used by the CNS to reproduce an internal representation of three-dimensional space and our own self-motion within this space.
Peripheral vestibular input has been studied ever since in attempt to fully characterise its contribution to our sense balance. Recent advances in our understanding of this critical peripheral input, together with technological and biomedical developments, means it is now possible to contemplate an effective vestibular prosthesis based on miniaturized gyroscopes, signal processors, electrical stimulators and electrodes. Despite the small numbers of groups involved in this field of research, progress is being made.
For example, in October last year Jay Rubinstein and his colleagues at the University of Washington initiated the first human feasibility studies of an implanted vestibular neurostimulator based on commercial cochlear implant technology.
Although not strictly a fully functional vestibular prosthesis, this device is aimed at preventing or attenuating the debilitating symptoms of dizziness and vertigo associated with Meniere’s disease.
A more comprehensive approach towards a vestibular prosthesis however is being developed by Charley Della Santina’s group at Johns Hopkins who will be presenting more detailed information on a head mounted, semi-implantable multichannel vestibular prosthesis (MVP). In short, although further work in many areas is still required before a viable balance prosthesis becomes a reality, nevertheless these challenges are being rapidly overcome.
A realistic hope is that in the not too distant future a vestibular prosthesis will repeat the astonishing success of another inner ear device, the cochlea implant.
Professor of Otolaryngology – Head & Neck Surgery and Biomedical Engineering
Director of the Johns Hopkins Vestibular NeuroEngineering Lab
Johns Hopkins University School of Medicine
Dr. Della Santina received his PhD in Bioengineering from the University of California at Berkeley, where his work focused on development of micromachined silicon devices for chronic multi-unit interfacing to the auditory/vestibular nerve. Since completing his medical degree at the University of California at San Francisco and residency at Johns Hopkins, he has been a clinician-scientist on the faculties of the Johns Hopkins Departments of Otolaryngology – Head & Neck Surgery and Biomedical Engineering.
As a board-certified otologic/neurotologic surgeon, Dr. Della Santina specializes in treatment of disorders of the middle and inner ear. His clinical interests include restoration of hearing (via cochlear implantation and other implantable devices for treatment of conductive and sensorineural hearing loss) and management of patients who suffer from vestibular disorders. He frequently lectures on these topics, and he is the author of multiple related clinical research articles, reviews and book chapters.
His laboratory research centers on development of a multichannel vestibular prosthesis intended to restore inner ear sensation of head movement. His >50 publications include studies characterizing inner ear physiology and anatomy; developing novel clinical tests of vestibular function; and clarifying the effects of cochlear implantation, superior canal dehiscence syndrome, and intratympanic gentamicin therapy on the vestibular labyrinth.
His recent honors include an American Otological Society Clinician-Scientist Award, the Robert Bárány Society Young Scientist of the Year Award, the American Neurotology Society Frank M. Nizer Lectureship, the ENTER Foundation Award for Innovation in Otolaryngology, the ENT-UK Gordon Smyth Lectureship, and induction into the American Otological Society.
Charles C. Della Santina*, Chenkai Dai, Gene Y. Fridman, Natan S. Davidovics,
Bryce Chiang, Mehdi A. Rahman, Nicolas S. Valentin, Daniel J. Sun, Abderrahmane Hedjoudje, JoongHo Ahn, Americo A. Migliaccio, Russell Hayden, TjenSin Lie, HongJu Park, Iee Ching W. Anderson, Sophia Lyford-Pike, Yuri Agrawal, John P. Carey, Lloyd B. Minor, Shan Tang
Vestibular NeuroEngineering Lab, Departments of Otolaryngology- Head & Neck Surgery and Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, MD USA
Bilateral loss of vestibular sensation disables individuals injured by ototoxic medications, surgical trauma, infection, Ménière’s disease or other insults to the labyrinth. Without input to reflexes that normally stabilize the eyes and body, affected patients suffer blurred vision during head movement, postural instability, and chronic disequilibrium. While individuals retaining some residual sensation usually compensate for their loss through rehabilitation exercises, others are left with no adequate treatment options. Data from a recent large-sample national health survey suggests that adults with bilateral vestibular deficiency (BVD) suffer a 14-fold increase in fall risk, and 41% report missing work (an average of 48 days/yr) due to their symptoms.
A prosthesis that senses head movement and modulates activity on branches of the vestibular nerve could significantly improve quality of life for these otherwise chronically dizzy patients, who may number up to 3 million worldwide.
Similar to a cochlear implant in concept and size, the Johns Hopkins Multichannel Vestibular Prosthesis (MVP) comprises inertial sensors of head movement, a microcontroller, and current sources switched between pairs of electrodes implanted within the vestibular labyrinth. Using 3D oculography, video tracking of freely mobile animals, evoked potentials and otoacoustic emissions, we have characterized eye movements, gait and hearing outcomes in rodents and rhesus monkeys implanted with MVP electrodes after being rendered bilaterally vestibular-deficient via treatment with gentamicin and/or plugging of semicircular canals.
MVP activation partially restores a normal angular vestibulo-ocular reflex (VOR) for head rotations about any axis of rotation in 3D space. Several advances in coding scheme and hardware, including “vector precompensation” (linear orthogonalization) of the stimulus-response mapping, comodulation of pulse rate and amplitude, and enhancements in electrode array design, have yielded significant performance improvements. Central nervous system plasticity significantly corrects for residual VOR errors over the first week of chronic MVP use. Hearing is preserved to within 14 dB after implantation in rhesus monkeys, and rodents demonstrate improved postural stability even when using an MVP that provides only rotational cues.
Progress to date strongly suggests that clinical application of a multichannel vestibular prosthesis is feasible and worth pursuing. Our efforts now focus on addressing issues prerequisite to human implantation, including refinement of electrode designs and surgical technique to enhance stimulus selectivity and preserve cochlear function, optimization of stimulus protocols, reduction of device size and power consumption, and development of inexpensive, self-contained vestibular testing systems to support wide deployment of MVP technology.
Supported by United States NIH/NIDCD R01DC9255
Conjoint Senior Lecturer
University of New South Wales
Americo A. Migliaccio was born in Sydney, Australia. He received a B.Sc. degree majoring in Computer Science and Mathematics and a B.E. degree (Honours, First Class) in Electrical Engineering from the University of Sydney. He also received M.Biomed.E and Ph.D degrees in Biomedical Engineering from the University of New South Wales. His doctoral work was performed at Royal Prince Alfred Hospital (Sydney, Australia). His postdoctoral work was performed at Johns Hopkins University (Baltimore, USA) where he is currently an Adjunct Assistant Professor in the departments of Otolaryngology—Head and Neck Surgery and Biomedical Engineering. In 2006 he co-founded the Vestibular NeuroEngineering Laboratory at Johns Hopkins with Dr. Charles Della Santina.
In 2008 he returned to Australia to establish the Balance and Vision Laboratory at Neuroscience Research Australia (NeuRA).
He is a Senior Research fellow at NeuRA and has a Conjoint Senior Lecturer appointment at the University of New South Wales. His basic science research focuses on the vestibular system in humans and animals, particularly mouse models, and his biomedical research is towards the development of vestibular diagnostic and rehabilitative systems.
Chairman, Division of Engineering
Co-Director, Neural Engineering Laboratory of Neurologic Surgery
Mayo Clinic, Rochester, Minnesota
Mr. Bennet’s Division of Engineering, composed of 64 technical staff, is responsible for the development and application of new technology for clinical practice and research. Major development efforts include deep brain stimulation, wireless physiological monitoring and minimally invasive surgery.
Mr. Bennet received a Bachelor of Science degree in Chemical Engineering from the Massachusetts Institute of Technology and a Masters of Business Administration from Harvard Business School.
Mr. Bennet joined the Mayo Clinic in 1990 with current and past appointments as Chair of Strategic Alliances, Vice Chair of Information Technology Standards & Architecture Subcommittee, Clinical Practice Committee Equipment Subcommittee, Information Technology Coordinating Executive Committee, Pharmacy and Therapeutics Committee, Medical/Industry Relations Committee as well as chair and membership in various workgroups and taskforces.
He has also served as a reviewer of Mayo Clinic Proceedings and the NIH Small Business Innovation Research program.
He has over 30 years of experience in technology development with organizations including W.R. Grace & Co., Exxon International and Amoco Chemicals. He has been a consultant to the National Institutes of Health and served on NIH site visit teams. He holds patents concerning semiconductor and optical technology and has founded several technology-based companies.
Kevin E. Bennet* and Kendall H. Lee, M.D., Ph.D.
Mayo Clinic, Rochester, Minnesota, USA
Deep brain stimulation (DBS), which has been used in over 80,000 people worldwide, has been demonstrated to be an effective neurosurgical treatment for several pathologies including Parkinson’s disease, essential tremor, epilepsy, Tourette’s Syndrome, depression, and chronic pain, among others.
To assess mechanism of action evoked by DBS, we have been performing electrochemical and fMRI investigations. We utilized 3.0T functional Magnetic Resonance Imaging (fMRI) in a large animal (pig) model to investigate the hypothesis that DBS results in site-specific activation of the neural structures within the neural network circuitry, including the prefrontal cortex in the case nucleus accumbens DBS and the caudate nucleus in the case of subthalamic nucleus (STN) DBS, which can be identified as changes in Blood Oxygenation Level- Dependent (BOLD) contrast with fMRI.
To that end, pigs were implanted in the NAc or STN, respectively, with Medtronic 3389 DBS electrodes and received various stimulation parameters (1-7 V, 60-130 Hz, and pulse widths of 100-500 msec). In each experiment, five identical trains of 6 sec duration stimulus pulses were alternated with six 120 sec rest periods. Simultaneously with the stimulation, the regions of BOLD signal change were evaluated using an echo planar imaging (EPI) sequence with the following imaging parameters: TR/TE: 3000/90, flip angle: 90, FOV: 150 mm x 150 mm, matrix: 64 x 64, slice thickness: 2.4 mm with no gap.
Consistent with our prediction, we observed stimulation time locked activation in the prefrontal cortex with nucleus accumbens DBS, and caudate nucleus with STN DBS. Our fMRI results suggest that DBS results in modulation of activity in areas distant from the electrode site. For electrochemical studies, we have developed an intraoperative neurochemical sensing technology called a Wireless Instantaneous Neurotransmitter Concentration Sensor System (WINCS) for use in experimental animals as well as in human patients.
WINCS measures sub-second changes in extracellular neurochemical concentrations by implementing both fixed-potential amperometry and fast-scan cyclic voltammetry (FSCV), and displays the data graphically in nearly real time. Under the Mayo Clinic approved IRB protocol, FSCV recordings from WINCS have been performed in Parkinson’s disease and essential tremor patients undergoing DBS surgery. The recordings were made in the caudate nucleus or subthalamic nucleus for Parkinson’s disease patient, or ventral intermediate nucleus of the thalamus for essential tremor patient.
Interestingly, during DBS electrode insertion, two oxidation peaks were detected at +1.5V and +1.0V that corresponds to adenosine release, at the FSCV electrode located 2 mm away from the DBS electrode. We suggest that the combination of these sophisticated in vivo electrochemical and fMRI techniques is safe and may provide important new insights into the neurobiological mechanisms of the action of DBS in humans.
Assistant Professor, Department of Electrical Engineering
Deputy Director of Biomimetic Systems Research Center
National Chiao Tung University
Herming Chiueh received his B.S. degree in Electrophysics from National Chiao Tung University, Hsinchu, Taiwan, and his M.S. and Ph.D. degrees in Electrical Engineering from University of Southern California, Los Angeles. From 1996 to 2002, he was with Information Sciences Institute, University of Southern California (USC).
Dr. Chiueh has participated the VLSI effort on several large projects at USC and most recently participated the development of a 55-million transistor processing-in-memory (PIM) chip. Currently, he is an Assistant Professor at the Department of Electrical Engineering and the Deputy Director of the Biomimetic Systems Research Center at National Chiao Tung University, Hsinchu, Taiwan.
His research interests include system-on-chip design methodology, low-power integrated circuits, mixed-signal circuits and systems, neural interface circuits, and biomimetic systems.
National Chiao Tung University, Hsinchu, Taiwan
In recent years, alternative treatments and devices are proposed to investigate and treat epilepsy in addition to pharmacological and surgical treatments. Several prosthesis devices with deep brain stimulation (DBS) or vagus nerve stimulation are becoming popular treatments for epilepsy clients. These devices use open-loop continuous neural stimulations to control medical refractory epilepsies complementarily with the limited effective rate around 45%.
Besides, by using continuous stimulations and an implantable battery, lifetime of such a device is often limited and periodically operations for clients are required to replace the battery/devices. To overcome the above limitations, this talk reviews our recent research on the neural prosthetic device with closed-loop epileptic seizure detection and conditional therapeutic stimulation.
The low-power analog front-end and bio-signal processing circuitries are used to detect the seizure’s signal before it propagates to the whole cortex and activating stimulations to stop the seizure. The integrated circuitries and electrodes are developed and verified. A prototype portable seizure controller is assembled according to designed circuits with real-time seizure detection algorithms.
Preliminarily experimental tests were done in two epileptic animal models using Long-Evans rats, indicating at least 92% seizure detection rate and suppression of seizure activity by conditional stimulation. Animal tests using the portable device with integrated chips and electrodes are currently undergoing. The proposed prosthetic device with closed-loop epileptic seizure detection and stimulation yields offers a promising treatment for absence epilepsy.
Professor, Dept. Medical Physics & Bioengineering
University College London
London, United Kingdom
Nick Donaldson studied Engineering and Electrical Sciences at Cambridge University. From 1977 to 1992 he worked for the Medical Research Council, Neurological Prostheses Unit, under the direction of Professor G.S. Brindley. In that period, his main field of research was the technology and application of implanted devices for the restoration of useful leg function to paraplegics. Since 1992, Donaldson has been Head of the Implanted Devices Group at University College London.
He has been Principal Investigator for many projects related to implanted devices and functional electrical stimulation. His research interests now include implanted device technology, the development of implanted devices that use natural nerve signals as inputs; stimulators of nerve roots; the use of electrical stimulation for recreational exercise of paralysed legs; and methods to encourage functional neurological recovery after injury.
Nick Donaldson, PhD
University College London
London, United Kingdom
Severe spinal cord injury (SCI) destroys voluntary control of the bladder and usually leads to hyper-reflexia so that the person is also incontinent. Restoring control of the bladder is the highest priority for most people after SCI.
The Finetech-Brindley implant is a very successful treatment: simple, reliable, inexpensive and users require little clinical support. The device stimulates the anterior sacral nerve roots to empty the bladder, and usually, the posterior roots are cut in the same operation as the implantation.
This deafferentation stops the hyper-reflexia, and therefore the incontinence. However, the number of hospitals that provide this treatment remains small; most urologists choose other methods, such as anticholinergic drugs and self-catheterisation.
The reason stated for not using the implant is often the deafferentation: it will cause an immediate concomitant loss of reflex erection in men and, in the longer term, if a new therapy arrives, it may prevent natural bladder control being restored.
Michael Craggs and others have suggested an alternative which he calls Conditional Neuromodulation. In this concept, the posterior roots are not cut but, like the anterior roots, are trapped so that they can be individually stimulated. The posterior roots are stimulated only when the bladder begins to contract which can interrupt the reflex.
In order that the surgery is confined to the spinal canal, we decided that the bladder contraction should be detected from the bladder afferents in these same roots.
We carried out a design study for a Conditional Neuromodulator a few years ago. At that time, we concluded that the idea was barely feasible and this stemmed from the decision to record from nerve roots. Not only was the signal probably too small but the noise requirement for the amplifier was so low that the amplifier largely determined the current consumption.
This, is turn, was a heavy load on the rechargeable battery and the inductive battery charger.
Recent work by the teams of James Fawcett and Stephanie Lacour has shown that the microchannel array may avoid this difficulty: the neural signals are larger and spikes from more than one axon can be discriminated.
In this paper I will review the results from recent experiments and consider what they imply for the feasibility of a Conditional Neuromodulator.
Chief technology officer
NICTA (National Information and Communications Technology Australia)
Dr John Parker leads NICTA’s efforts to develop novel medical implant technologies. His research aims to develop fundamental new technologies to support new systems and implantable therapies to help those who suffer from a range of neurological disorders.
Exploring the potential for smaller and more sophisticated medical prosthesis is a key aspect of Dr Parker’s research, but it will also aim to provide breakthrough technology to enable new treatments.
Dr Parker was previously Chief Technology Officer and executive director at Cochlear, the ASX-listed company credited with developing the world’s first commercially viable cochlear implant, or Bionic ear. This is a surgically implanted electronic device that allows even profoundly deaf people to experience a sense of sound. It works by stimulating auditory nerves inside the cochlea with electronic signals.
Dr Parker is a Fellow of the Australian Academy of Technological Sciences and Engineering. His career at Cochlear spanned over 13 years and he worked in many areas of the business. Dr Parker has authored numerous publications and patents and has been a director of both listed and non-listed technology business both in Australia and Overseas.
John L. Parker* (ab), Dean M. Karantonis (a), Peter S. Single (a), Milan Obradovic (a), James Laird (a), Michael J. Cousins (C)
a National Information and Communications Technology Australia, Eveleigh, NSW Australia
b Graduate School of Biomedical Engineering, University of New South Wales, Kensington, NSW Australia
c Pain Management Research Institute and Kolling Institute, University of Sydney at the Royal North Shore Hospital, St Leonards, NSW Australia
Spinal cord stimulation for the management of chronic neuropathic pain has been in use for over 30 years however there is still no clear understanding of its mechanism of action.
We have developed methods to record compound action potentials and characterize the neuronal populations responding to SCS in an animal model and also in humans.
The mechno-sensory Aβ fibres respond at clinically relevant stimulation levels.
At higher stimulation levels additional responses are measured which correspond to the onset of unpleasant “side effects” so often experienced by users of SCS.
The direct measurement of neuronal properties provides valuable insight to mechanism of action and has broad implications for improvement to SCS therapies.
A study of the change in amplitude of the evoked potential with stimulus characteristics provides essential data from which to develop new stimulation paradigms and new programing techniques.
Vice-President and Director of Advanced Materials Research
EIC Laboratories, Inc.
Norwood, Massachusetts, USA
Dr. Cogan received a B.Sc. degree in Mechanical Engineering and a M.S. degree in Materials Science from Duke University in 1975 and 1977, respectively. He obtained a Sc.D. in Materials Science from the Massachusetts Institute of Technology (MIT) in 1979. From 1979 to 1980, Dr. Cogan was a Visiting Assistant Professor in Mechanical Engineering and Materials Science at Duke University where he worked on amorphous semiconductor materials for solar cells.
He returned to MIT as a Research Associate in 1981. His research at MIT focused on the fabrication and high magnetic field properties of superconducting metal-matrix composites. In 1983 he joined EIC Laboratories. Dr. Cogan’s research interests at EIC have included thin-film electrochromics for optical switching devices, materials for encapsulating implanted medical devices, and electrode materials for stimulation and recording in prosthetic and pacing applications.
Dr. Cogan is presently working on electrodes for retinal prostheses, vision prostheses using intracortical stimulation, coatings for cardiac pacing and defibrillation, microECoG recording arrays, and on neurotrophin releasing polymers for intracortical electrodes. His research interests broadly focus on the electrochemical properties of the electrode-tissue interface and on methods for controlling and stabilizing the interface for stimulation and recording applications.
Stuart F. Cogan, ScD
EIC Laboratories, Inc.
Norwood, Massachusetts, USA
Emerging prostheses and electrical stimulation therapies will employ microelectrodes chronically implanted in the central nervous system (CNS). These microelectrodes must stimulate or record from small populations of neurons in a reliable and predictable manner for many decades. The electrochemical stability of sputtered iridium oxide (SIROF) microelectrodes chronically implanted in the CNS is reviewed in the context of recent studies of electrodes implanted intracortically in cat and subretinally in pig. The critical properties of stimulation charge-injection capacity and impedance at recording frequencies have been measured for implantation times up to 300 days intracortically and for up to 110 days subretinally.
As expected, significant changes in electrode behavior associated with tissue response were observed for both placements and there was a general decline in the ability of the electrodes to inject charge while also avoiding water electrolysis potentials. The charge storage capacity, measured by cyclic voltammetry, of the penetrating intracortical electrodes increased with implantation time while their 1 kHz impedance decreased. These observations suggest a rate (current density) dependent competition between tissue response which increases impedance and electrolyte leakage under insulation which increases the apparent surface area of the electrodes.
Cyclic voltammetry (CV), impedance spectroscopy, and voltage transient measurements were employed in an effort to separate tissue and electrode effects, and the results of this study are presented. The subretinal placement employed planar microelectrode arrays fabricated on polyimide.
The voltage transient response of the subretinal electrodes indicated an increase in impedance with implantation time although the CV charge storage capacity remained relatively constant. On explantation, the low pre-implantation impedance of the electrodes was substantially recovered, suggesting that the changes observed with the planar arrays are primarily due to tissue response. The maximum in vivo charge-injection capacity of the SIROF electrodes was also compared with that measured in physiological saline at different current pulse widths and over a range of interpulse bias levels.
For most conditions, the 180 day in vivo charge capacity is about a factor of five lower. While greatly reduced, the in vivo charge capacity was well-above expected charge thresholds for intracortical stimulation. However, these results should be interpreted with caution in view of the probable electrolyte leakage which results in an overestimate of the charge-injection capacity. The prospects and issues for achieving chronic stability of stimulation and recording microelectrodes are discussed.
Director, Neural Engineering Program
Huntington Medical Research Institutes
Pasadena, California, USA
Douglas McCreery received the B.Sc. and M.Sc. degrees in Electrical Engineering and the Ph.D. degree in Biomedical Engineering from the University of Connecticut in 1966, 1970, and 1975, respectively. He completed his postdoctoral training in the Department of Neurosurgery at the University of Minnesota. He now lives in Pasadena ,CA, USA where he is director of the Neural Engineering Program at Huntington Medical Research Institutes.
His research interests include the development of neuroprostheses and devices for neuromodulation for the central nervous system, and the physiologic and histologic effects of electrical stimulation of the central and peripheral nervous systems.
Neural Engineering Program, Huntington Medical Research Institutes
Pasadena, California, USA
Neurons adjacent to a chronically implanted iridium microstimulating electrode with a geometric surface of no more than 500 µm2 (25 µm in diameter) can be stimulated safely for long intervals.
This dimension is comparable to the diameter of individual neurons in the mammalian CNS, suggesting that the spatial resolution of a microstimulating array will be limited by our ability to fabricate durable devices with numerous conductors and independent electrode sites, and by the tolerance of the neural substrate to the introduction and residence of many closely-spaded electrode shanks.
For example, it has been shown that long-term residence of rigid, 50 micron iridium shanks induces significant loss of neurons in the cerebral cortex within 100 µm of the shanks. Additional problems arise when the application is a neuroprosthetic or neuromodulation device that must provide high spatial resolution, requiring a high spatial density of microelectrode sites.
With this type of device, interleaved stimulation of proximal electrode sites will help to preserve spatial resolution, but may engender depression of neuronal excitability due to redundant stimulation of neurons from adjacent electrode sites.
The volume of a spatially dense array of electrode shanks will produce significant displacement and strain within the tissue, and so the supporting electrode shanks of should have sufficient strength and rigidity to penetrate into the neural substrate, but with minimal cross-sectional area in order to minimize tissue strain.
The supporting shanks must contain numerous electrical conductors to the many electrode sites, but must exhibit long life in vivo with minimal cross-talk between conductors. Ideally, the shanks should become flexible (after implantation) in order to reduce tissue injury related to micromotion. Some of these requirements are very difficult to reconcile, and all pose major challenges to current microfabrication technologies.
East Melbourne, Australia
Andrew Wise completed his PhD in 2001 at Monash University, where he studied neurophysiology of the sensorimotor system. He is currently a Research Fellow at the Bionics Institute. Dr. Wise’s research interests include strategies to improve the performance of the cochlear implant and also therapies to protect and/or regenerate the auditory system after deafness. His research interests are focused on the use of cochlear implantation and drug delivery to prevent degeneration of the cochlea following deafness, and on examining the effects of this treatment on auditory function.
Andrew. K. Wise
Bionics Institute, Australia
Auditory neurons, the target cells of the cochlear implant, undergo progressive degeneration following deafness, ultimately leading to cell death. The delivery of drugs to the cochlea, such as neurotrophins, has been shown to protect auditory neurons and promote undirected regrowth of their peripheral processes.
However, an effective strategy to safely deliver therapeutics is yet to be established thus limiting the potential clinical benefits that drug delivery to the cochlea may provide. This talk will discuss some of our research that aims to deliver drugs in a safe and effective manner that is clinically relevant.
We have explored the use of a number of drug delivery techniques that include mini pumps, ‘smart’ polymers, cell-based therapies, viral vectors and nanoparticles. This talk will discuss these techniques and focus on some recent results from experiments using cell-based delivery.
We have used cells harvested from the choroid plexus that naturally produce neurotrophins. The cells were encapsulated in a biocompatible alginate matrix that immuno-isolated the implanted cells from the host and enabled the produced neurotrophins to be released into the cochlea.
The cell-based therapies provided effective neural protection that was enhanced with chronic electrical stimulation, delivered by a clinical device. Furthermore, resprouting of the peripheral processes was observed following treatment.
The preservation and regrowth of auditory neurons may lead to improvements in clinical outcomes for cochlear implant recipients when combined with new electrode arrays and processing strategies that take advantage of greater neural populations and improved electrode-neural interface.
In addition to neural protection and regrowth, the safe and effective delivery of therapeutic drugs to the inner ear may also enable the preservation or restoration of residual sensory function that is known to deteriorate following cochlear implantation.
The application of drugs to protect and maybe even restore both neural and sensory elements is likely to be a key factor in improved clinical outcomes for cochlear implant recipients in the future.
Funding has been provided by The Garnett Passe & Rodney Williams Memorial Foundation, the National Institutes of Health (HHS-N-263-2007-00053), and Operational Infrastructure Support Program of Victorian Government.
Principal Research Engineer
Cochlear Ltd., Australia
Brett Swanson received a Bachelor of Electrical Engineering from the University of New South Wales (Sydney, Australia) in 1985. He joined Cochlear Ltd in Sydney in 1992. He has worked on custom integrated circuits for cochlear implants and sound processors, clinical software, and digital signal processing (DSP) firmware. In 2008 he received a PhD from the University of Melbourne for a thesis entitled “Pitch Perception with Cochlear Implants”.
His present work covers cochlear implant sound processing and perception, cochlear implant system design, and use of CI technology in non-hearing applications.
Brett Swanson, PhD
Cochlear Ltd., Australia
A cochlear implant restores a sense of hearing to a person with severe to profound deafness. Most recipients achieve good speech perception under good listening conditions, but the two big challenges are speech perception in noisy conditions, and pitch perception.
Signal processing algorithms to address speech in noise include dual-microphone adaptive beam forming, multi-band gain control, and SNR-based noise cancellation. The only demonstrated method of improving pitch perception is to make use of residual acoustic hearing, with a contralateral hearing aid, or with a hybrid device which incorporates low-frequency acoustic stimulation in conjunction with a short electrode array.
Attempts to improve pitch perception by changing the sound processing and stimulation strategy have not been successful.
This is most likely due to our inability to reproduce the spatio-temporal neural firing pattern evoked by resolved harmonics in normal hearing. Research into more focused stimulation may provide improvements.
Senior Principal Research Engineer
Technology Cluster Leader
Cochlear Ltd., Australia
Paul Carter has a bachelor’s degree in Physics and a PhD in microelectronics from University of Southampton, UK. After working for Texas Instruments and Plessey Electronics Research on the design of high-density memory chips, he joined the University of Wollongong as a Lecturer at the Department of Electrical and Computer Engineering.
After five years in academia, he joined Cochlear Ltd. in 1992 as the founding member of their long-term strategic R&D group. Dr. Carter’s experience with Cochlear includes a customer troubleshooting role in the US and the development of several products as a project manager.
In 2005 he was appointed as Cochlear’s Innovation Manager, in order to apply a systematic approach to the company’s innovation practices. He currently jointly manages the “Electrodes and Interfaces” technology cluster for Cochlear and is still actively involved in research. In his career, Dr. Carter has been granted around a dozen international patents, has won a similar number of joint academic/industry research grants and has authored numerous journal and conference articles.
Dr. Carter is currently an adjunct Professor in Engineering at Sydney University where he actively researches and runs a course titled “Fundamentals of Neuromodulation”.
Paul Carter, PhD
Cochlear Ltd., Australia
The cochlear implant industry is today worth well over a billion dollars per annum and the vast majority of its recipients successfully hear sound due to the passage of stimulation current between electrodes inside the cochlea and one or more electrodes outside the cochlea. And yet the path by which this current finds its way from one electrode to the other is largely unknown.
This talk will ask where the current flows in its journey between the electrodes and what implication this has on the experience of the recipient. It will look at past efforts that have been made to answer this question at three different levels of scale: i) throughout the whole head, ii) within the cochlea and iii) near the site of the intracochlear electrode.
It will also discuss the early days of attempts by Sydney-based researchers to answer this question and will present some very early data from this research.
Associate Professor, Center for Sensory-Motor Interaction
Associate Professor of Electrical and Computer Engineering
Aalborg University, Denmark
Dr. Jensen graduated as an M.Sc.EE. in 1996, and in 2001, she finished her Ph.D. dissertation in biomedical science and engineering at Aalborg University. The focus of the Ph.D. work was to study the feasibility of using muscle afferent signals as natural sensory feedback for FES systems.
Presently, Dr. Jensen heads the ‘Neural Engineering and Neurophysiology of Movement’ (NENM) research group at the Aalborg University which investigates basic neuromuscular mechanisms, their functional consequences mediating both acute adjustments (e.g., arousal, muscle fatigue, pain) and chronic adaptations (e.g., aging, gender, training, stroke, rehabilitation), and methods to restore, replace, and modulate lost or impaired motor functions. Her special focus areas include neural prosthesis applications and neural interfaces.
Aalborg University, Denmark
Amputation of a limb may result from trauma or surgical intervention. The amputation traumatically alters the body image, but often leaves sensations that refer to the missing body part, the phantom limb. In 50-80% amputees, phantom limb pain (PLP) develops in the lost limb.
Today, it is not completely understood why the pain occurs, and there are no fully effective treatment. The favorable effect of enhancing the sensory feedback related to the missed limb to alleviate PLP has been studied in the recent years. However, selective, intrafascicular, electrical stimulation of severed nerves have proved to elicit tactile or proprioceptive sensations.
In the TIME project we hypothesize that given sufficient, selective control a neural interface may be able to artificially evoke sensations and eventually relieve PLP. Our objective was therefore develop an innovative Human Machine Interface (HMI) that to apply multi-channel microstimulation to the nerve stump of an amputee volunteer to manipulate his/her phantom limb sensations, and explore the possibility of using the method as a treatment for PLP. The talk will aim to present the background and results of the TIME project, including a discussion on the use of electrode to achieve selective activation of peripheral nerves.
Director of the Clinical Exercise Rehabilitation Unit
Professor of Clinical Exercise Sciences
University of Sydney, Australia
Dr. Davis received his Ph.D. degree at the University of Toronto in 1986. Originally trained as a clinical exercise physiologist, Dr Davis has published numerous peer-reviewed scientific and clinical papers on exercise therapy for rehabilitation following spinal cord injury, hemiplegic stroke and cardiac failure patients, as well as the use of Functional Electrical Stimulation in paraplegia and hemiplegia.
He has built his programme of research around the key theme of using innovative technologies to improve the quality of physical exercise and functional outcomes in patients with acquired neurological disability, cardiology impairments and musculoskeletal conditions.
Since 1990, he has conducted invited workshops, lectures and symposia with international scope in his research area of Exercise Therapy for Special Populations. In addition, he has published 19 book chapters, over 80 peer-reviewed journal articles and more than 100 abbreviated communications in proceedings of scientific meetings. Professor Davis is Co-Investigator of the Australian clinical trial “SCIPA (Spinal Cord Injury & Physical Activity): Intensive exercise from acute care to the community”.
Since 2000, Professor Davis has been Principle/Chief Investigator on research grants exceeding $A13.3M, including current National Health and Medicine Research Council, Australian Research Council and EU Framework 6 funding. He collaborates extensively with clinical institutions on multi-disciplinary research projects involving FES in paraplegia and tetraplegia, using therapeutic exercise to promote recovery following hemiplegic stroke and exercise rehabilitation after spinal cord injury.
University of Sydney, Australia
This presentation will examine whether FES-evoked exercise and walking are the best way to promote gains in aerobic fitness and other health outcomes for spinal cord-injured individuals. Key studies from the scientific literature were contrasted, supporting or rebutting the popular view that such exercise is primarily aerobic metabolism, and hence FES-evoked physical training will lead to gains of peak aerobic fitness and the health outcomes that proceed from exercise.
The evidence for and against the “exercise hypothesis” that physical training via FES will reduce cardiovascular risk and lower disease burden in the SCI population was also be examined.
A careful analysis of these key keynote studies from the literature suggests that FES-cycling and FES-gait do not always improve aerobic fitness nor lead to gains in muscle or bone health outcomes in wheelchair users with spinal cord injury.
Director of the Neural Systems Engineering Laboratory
Associate Professor of Electrical and Computer Engineering
Michigan State University
Dr. Oweiss received his B.S. (1993) and M.S. (1996) degrees with honors in Electrical Engineering from the University of Alexandria, Egypt, and the Ph.D. degree (2002) in Electrical Engineering and Computer Science from the University of Michigan, Ann Arbor. He completed a post-doctoral training in Biomedical Engineering at the University of Michigan, Ann Arbor in 2002. In 2003, he joined the department of Electrical and Computer Engineering and the Neuroscience Program at Michigan State University, where he is currently an associate professor and director of the Neural Systems Engineering Laboratory.
His research interests span the areas of statistical signal processing and information theory, neural integration and coordination in sensorimotor systems, computational neuroscience and brain-machine interfaces.
Exploring the potential for smaller and more sophisticated medical prosthesis is a key aspect of Dr Parker’s research, but it will also aim to provide breakthrough technology to enable new treatments.
Dr. Oweiss is a senior member of the IEEE and a member of the Society for Neuroscience. He served as a member of the board of directors of the IEEE Signal Processing Society on Brain Machine Interfaces, and continues to serve on the technical committees of the IEEE Biomedical Circuits and Systems, the IEEE Life Sciences, and the IEEE Engineering in Medicine and Biology societies. He was awarded the excellence in Neural Engineering award from the National Science Foundation in 2001.
His lab is currently supported through the Neural Interfaces Program (NIP) and the Repair and Plasticity Program (RPP) at the National Institute of Neurological Disorders and Stroke, as well as DARPA’s Reliable Central-Nervous-System Interfaces (RCI) program. He is the editor and co-author of the book: Statistical Signal Processing for Neuroscience and Neurotechnology, published by Academic Press in 2010.
Karim Oweiss, PhD
Associate Professor of Electrical and Computer Engineering, Michigan State University
Brain stimulation is a direct way to influence brain activity through a man-made device, with an ultimate goal of improving the lifestyle of neurologically impaired subjects.
For stimulation to be optimally delivered, some means of translation should occur between the signals that the brain uses for its internal communication and those used by the stimulator to achieve a desired functional outcome.
In this talk, I will briefly overview the challenges associated with delivering stimulation in the context of prosthetic limb control.
I will discuss the importance of establishing a readout mechanism of the causal effects of stimulation on neural ensemble activity in that context.
I will conclude by outlining a strategy to use this readout to optimize the delivery of stimulation to increase the effectiveness of neural interfaces in prosthetic limb control to accelerate their deployment in clinical applications.
Professor and Chair, Dept. Biomedical Engineering
Florida International University, Miami, USA
President and co-founder, Advensys LLC, Scottsdale, USA
Dr. Jung holds a bachelor’s degree in electronics and communications engineering from the National Institute of Technology (Warangal, India), a MS and PhD degrees in biomedical engineering from Case Western Reserve University, completing the latter in 1991. Prior to joining FIU, she was an Associate Professor and co-director of the Center for Adaptive Neural Systems at the Arizona State University.
Dr. Jung is an entrepreneur and a leader in establishing academic-clinical-industrial partnerships in neural engineering and computational neuroscience research. Her team is developing a novel fully implanted neural interface between a myolectric prosthetic hand and peripheral nerves of below-the-elbow amputees.
As President and co-founder of Advensys, LLC she received the US Army funding to develop powered lower-limb splints for evacuating injured soldiers from the urban battlefield. This patent-pending technology also has promise for providing “crutch-free” walking after ankle injuries.
She served a multi-year term as a President of the Organization for Computational Neurosciences, an international organization that serves the global community of computational neuroscientists. She is a Senior Member of IEEE and the Society of Women Engineers. She is also Associate Editor for the journals IEEE Transactions on Biomedical Engineering, Neural Networks and Review Editor for Frontiers in Neuromethods.
Ranu Jung, PhD
Florida International University, Miami, USA
The nervous system functions by generating patterns of neural activity. Using a NeuroDesign approach, biohybrid systems can access the patterns of neural activity, influence this pattern in realtime, and induce plasticity by altering the pattern formation mechanisms.
Bidirectional communication at multiple points of interface between the endogenous nervous system and the exogenous man-made systems offers opportunities for closed-loop control of co-adaptive systems and biomimetic approaches can be used in the design of the exogenous system to enhance the integration of the biotic and abiotic.
This talk will present some of our work in using neural models, designing neuromorphic systems and developing neural prostheses. A neural model of spinal motor pattern generating circuitry of lower vertebrates will be presented.
We have used this model to design neuromorphic controllers to interface with an active spinal cord, to adaptively control orthoses to allow mobility after lower limb trauma in people and to adaptively control movement using neuromuscular electrical stimulation of paralyzed muscles in a rodent model of movement therapy after incomplete spinal cord injury.