“What Biology Teaches Us About Orthotic and Prosthetic Design”
Hugh Herr, Ph.D.
Associate Professor, Program in Media Arts and Sciences, Associate Professor
MIT-Harvard Division of Health Sciences and Technology
Massachusetts Institute of Technology
A long-standing goal in rehabilitation science is to apply neuromechanical principles of human movement to the development of highly functional prostheses and orthoses. Critical to this effort is the development of actuator technologies that behave like muscle, device architectures that resemble the body’s own musculoskeletal design, and control methodologies that exploit principles of biological movement. In this lecture, I discuss how agonist-antagonist actuation, polyarticular limb architecture, and reflex behaviors can result in quiet, stable, and economical legged mechanisms for walking and running. Neuromechanical models are presented to examine the importance of limb morphology and neural control on locomotory performance. These models are then used to motivate design strategies for prosthetic and orthotic mechanisms.
COL Geoffrey Ling, M.D, Ph.D.
Defense Sciences Office
Traumatic amputation of a limb is a particular devastating combat related injury. Great advances have been made for lower extremity limb loss with currently available prosthetic legs/feet providing remarkable functionality. The same is not true for upper extremity limb loss. In the Revolutionizing Prosthesis research program, two prosthetic arms have been developed. The first is a noninvasive arm that is controlled by foot switches, body motion and local control. It provides a remarkable level of functionality that meets many basic activities of daily living. The second is a brain cortically controlled arm that promises to fully restore normal functionality, including dexterous five finger control. The engineering and neuroscience efforts that are the core of the program have led to remarkable advances. Both arms have been created. Both arms are modular so that they can be used by any upper extremity amputee patient. The noninvasive arm is now in advanced human clinical optimization trial and should be available commercially by 2012. The cortical control arm has entered into human clinical trial in 2011 with the first demonstration of a human controlling the DARPA APL arm using electrocorticography.
“Neuroprosthetic Devices: The Path from Proof-of-Concept Laboratory Demonstrations to Robust Clinical Use”
Kip Ludwig, Ph.D.
Program Director, Repair and Plasticity
Over the last thirty years proof of concept laboratory experiments have shown that neuroprosthetic devices have great promise to reduce the burden of numerous neurological disorders. Despite this promise, relatively few neuroprosthetics have been taken beyond laboratory experiments, and even fewer have progressed beyond "first in human" feasibility studies to provide meaningful, long-term improvements in patient quality of life. For neuroprosthetic devices to truly revolutionize patient care and achieve widespread user acceptance, they must make the leap from experimental studies in the lab or clinic to robust and reliable at-home patient use. Dr. Kip Ludwig will give an overview of present trends in neurotechnology and discuss the necessary steps to translate these device concepts to meaningful improvements in patients’ health, function and quality of life. He will look at commonalities between neuroprosthetic devices that have successfully translated to at-home patient use, and outline opportunities to assist translation available at NINDS to academics and industry.
“Hybrid biological/non-biological actuation system to enable direct integration of a
prosthetic to an amputation site”
James J. Hickman, Ph.D.
Professor, NanoScience Technology, Chemistry, Biomolecular Science and Electrical Engineering
University of Central Florida
Central nervous system control of prosthetic limbs is essential to return a high quality of life to an amputee. Currently, prosthetic systems under development consist of indirect transduction methods that are either non-invasive, such as pressure sensitive transducers, or invasive, to include electrodes directly into the cortex or electrodes into the peripheral nerves or a combination thereof, such as a reinnervation of the nerves into a chest muscle with pressure transducers placed on the chest. An ideal solution for restoring more realistic function in an amputee would be the integration of the prosthetic with the uninjured tissue in a way that restores normal input/output or sensory/motor function across the healed wound to enable direct control of the prosthetic through the CNS. We are developing the systems necessary to create this interface using MEMs technology. This presentation will describe in vitro data that has demonstrated the regrowth of functional motoneurons combined with myotubules to create a hybrid biological/non-biological actuator. We have demonstrated that axons will innervate the hybrid actuators and transduce a neuron’s electrical signal from a muscular contraction of a myotubule integrated with a silicon device. The sensory neurons are integrated with an electrical transduction system to allow the spinal reflex arc loop to be completed. We have also regrown adult motor and sensory neurons and demonstrated their integration with a non-biological actuation system. This system holds promise to provide a new approach to prosthetic integration
“Bidirectional neural interface systems enabling closed loop feedback control of prosthetic devices”
Florian Solzbacher, PhD
Director of the Utah Nanofabrication Laboratory, Co-Director of the Utah Nanotechnology Institute, President and Executive Chairman of Blackrock Microsystems and of Blackrock Neuromed
University of Utah
The talk will present recent advances in fully integrated wireless neural interface technology for chronic use. It is a technology platform and basic tool for neuroscience and neuroprosthetics researchers and clinicians designed to allow full bandwidth recording at 30 kS/s for up to 200 channels/2 cortical Utah Electrode Arrays, wireless data transmission and simultaneous stimulation from up to 3 stimulating electrode arrays such as to cover high temporal and spatial resolution for recording and stimulation, while allowing placement across a distributed area of cortical tissue in vivo for chronic studies. Long term reliability in vitro data and in vivo data will be presented.
“Advanced Neural Prosthetics: Prospects and Challenges”
Gerwin Schalk, Ph.D.
Research Scientist, Neural Injury & Repair
Associate Professor, School of Public Health
Wadsworth Center, New York State Department of Health
Advanced Neural Prosthetics: Prospects and Challenges
Assoc. Prof., Dept. of Neurology, Albany Medical College
Assoc. Prof., Dept. of Biomed. Sci., State Univ. of New York at Albany
Adj. Assist. Prof., Dept. of Neurosurgery, Washington Univ. in St. Louis
Adj. Faculty, Dept. of Biomed. Eng., Rensselaer Polytechnic Institute
Adj. Full Prof., Dept. of Elec. and Comp. Eng., Univ. of Texas at El Paso
In 1938, Herbert Jasper, a young Canadian neuroscientist, sent a Christmas card to Hans Berger, the inventor of the electroencephalogram. In this card, brain waves emanate from Jasper's scalp and make up Jasper's Christmas greetings to Hans Berger. In the 70 years since then, many science-fiction authors and scientists have speculated that it may be possible to use signals recorded directly from the brain to communicate messages to the outside world using a brain-computer interface (BCI).
The field of BCI research began to develop about 25 years ago and transformed from initial isolated demonstrations by a few groups into a large scientific enterprise that is currently producing more than 100 peer-reviewed articles and several dedicated conferences and workshops each year. This level of productivity is reflective of the large and continually growing enthusiasm by the scientific community, funding agencies, and the public. BCI demonstrations described to date include four-dimensional control of a robotic arm using implanted microelectrodes, three-dimensional control of a computer cursor using scalp-recorded EEG, and spelling at a rate of more than 20 characters per minute using subdurally recorded ECoG. At the same time, despite substantial increases in our understanding of nervous system function, better mathematical approaches to interpret this function, and despite the pervasive availability of cheap and powerful computers, BCI performance is still poor compared to conventional motor performance, has in important aspects improved only marginally over the past 20 years, and we still have only a very rudimentary understanding of the basic principles that produce and optimize BCI control. Most importantly, despite recent encouraging developments, the field of BCI research has yet to produce solid evidence that BCI systems can actually improve people's lives or provide other distinct advantages.
In this talk, I will review the underlying rationale for BCI research, the field's strong and growing enthusiasm, the impressive demonstrations produced by the field, and the sobering reality of the remaining substantial limitations. I then propose several reasons for these shortcomings, and provide suggestions for future research directions that are implied by this analysis.
“Advances in Electromyogram (EMG) Signal Analysis/Modeling and Their Application to High-Fidelity Prosthesis Control”
Ted Clancy, Ph.D.
Associate Professor, Electrical & Computer Engineering
Worcester Polytechnic Institute
The surface electromyogram (EMG) of remnant muscles has been used for a number of years to command the operation of powered prosthetic limbs. EMG is most closely related to the neural input to muscles. We have been developing advanced processing techniques and musculoskeletal models to improve the “measurement” of this neural input signal, along with the estimation of muscle tensions and joint torques from EMG. Our work has been performed primarily at a basic laboratory level of investigation, but has application in areas including prosthesis control, ergonomics and clinical biomechanics.
This presentation will discuss two primarily technologies that we have been developing—EMG signal whitening and EMG-torque modeling. The EMG signal is known to be rather “noisy,” a consequence of the asynchronous firing of many active motor units within the muscle. Whitening reduces this noise. A higher quality signal is then available for EMG control. Recent results using whitening in EMG pattern classification for prostheses control will be discussed. In addition, most prosthesis control algorithms use relatively simple schemes to relate EMG to motor torque. For more natural control, the EMG-torque relationship should more closely mimic that of the human body. We will present results on our effort to do so, for forces exerted about the human elbow. High fidelity EMG-based prosthesis control should be a useful precursor to more direct neural control.
“Designing Neural Circuits In Vitro”
Bruce Wheeler, Ph.D.
Professor, J. Crayton Pruitt Family Department of Biomedical Engineering,
University of Florida
The wild idea that nerve cells grown in culture could have reliable computational function, while still a wild idea, is closer to reality than is reasonable to expect, thanks to applications of both engineering and applied biology. The metaphor works both ways: applications of more traditional engineering technologies – signal processing, electronics, microlithography, materials science – make possible the controlled growth, recording, and stimulation of nerve cells. In turn the goal is to design, construct, test, and utilize – in short to engineer – a working biological construct. In this lecture examples, mainly from the speaker’s laboratory, illustrate the component technologies that have been utilized in this pursuit, as well as examples illustrating how the approaching the problem as an engineer leads to the asking new questions.
Collaborator: Dr. GJ Brewer, SIU School of Medicine, Springfield IL. Support: NIH and NSF.
“The BEI Center for Neuroprosthetics: Past, Present and Future”
Grant McGimpsey, Ph.D.
Vice President for Research and Sponsored Programs, Professor of Chemistry
Kent State University
In 2005, the Bioengineering Institute (BEI) founded the Center for Neuroprosthetics in order to address the challenges of US military servicemen and women who had been injured in the Iraq and Afghanistan conflicts, particularly those who had lost limbs due to improvised explosive device (IED) attacks. Over the ensuing years the center has worked closely with the US Army Medical Research and Materiel Command, has developed research collaborations across the country and has embarked on promising new research paths that are aimed at helping amputee soldiers regain mobility, function and quality of life. At the same time the BEI has continued research efforts on the monitoring of soldier physiological condition and on the detection of IED's. The US military is now entering a new phase in its efforts in Asia and must address these changes while at the same time continue to care for those recovering from their wounds. The Center and its partners across the country will continue to work on advanced solutions for these soldiers.
Last modified: January 30, 2012 14:51:42