James L. Patton, PhD - US grants

Robotic manipulators are seen as a potentially important instrument for rehabilitation because they can be programmed to exert a variety of forces (force fields) while the subject moves. They can also be used repetitively, while monitoring and recording subject's performance, allowing more intensive and prolonged treatment than is currently feasible with a human therapist. The question that remains is what type of force field is best suited for assisting in the recovery of motor function in hemiparetic human subjects, and how should the stroke survivor be trained in such a force field. When normal subjects are exposed to a novel force field that disturbs their motion in a systematic fashion, they adapt progressively so that they exhibit characteristic after-effects when the disturbing force field is unexpectedly removed. Both the initial adaptation and the after-effects occur without subjects being aware of the adaptive process. Since after-effects can be predicted by dynamic models of the neuro-musculoskeletal system, I plan to use dynamic modeling techniques as a tool for designing forces that will yield desirable after- effects in hemiparetic stroke patients that show stereotypical errors in movement. Currently there is evidence that hemiparetic stroke patients recovery is enhanced when they experience assistive force fields. Other evidence suggests that training against resistive force fields during reaching movements may also help the patient perform a desirable motion once the resistive field is removed. The main goal of this project is to determine which type of field -- assistive or resistive -- is best suited to attaining desirable rehabilitation outcomes. To this end I will use a programmable two-link robot that exerts forces during reaching movements in the horizontal plane. I plan to determine first to what extent after-affects can be made to persist. I will then develop and test a computational framework that designs assistive and resistive force fields. Finally will determine whether assistive or resistive force fields are best suited for mediating the desired compensatory effects on movements in hemiparetic stroke survivors. The results of these experiments should favor the development and application of more sophisticated rehabilitation environments using robots and provide a clear direction for more long-term clinical trials in the area of robot assisted rehabilitation.

DESCRIPTION (provided by applicant): The purpose of this R13 application is to request support for a 2.5-day meeting that will provide a forum for the exchange of information between investigators who study robotics applied to rehabilitation. The meeting, entitled "New Frontiers in the Human-Machine Interface", will be held at the Northwestern University (NU) Chicago campus, with which the Rehabilitation Institute of Chicago (RIC) is affiliated, on June 28-July 1, 2005. We expect that the meeting will provide an opportunity to review current knowledge, to identify critical gaps in existing knowledge, and to formulate a research agenda that can address these issues. Scientifically, the field of rehabilitation robotics is on the verge of new frontiers in the areas of therapeutic robotics, the brain-machine interface, and the advent of electromechanical devices specially designed for contact with humans. The meeting will involve about 275 participants, including three invited keynote speakers, 26 invited speakers (9 of whom are women), approximately 100 trainees (graduate students and post-doctoral fellows), and a number of investigators in the field. One invited keynote speaker has already agreed to participate in the meeting. The meeting format will consist of three 45-minute keynote addresses (one per day, 30 minute), 40 podium presentations (15 minutes each, 16 per day), 2 poster sessions, and time for discussion at the end of each session. The meeting will encourage the participation of young investigators, women, minorities, and the disabled by reserving space for 8 travel awards reserved for representatives of these groups (two each). Furthermore, the conference has traditionally placed a high value on practical demonstrations of real robotic systems. To encourage this activity, the conference will provide 4 additional travel awards for users of technology to attend the conference, along with provide $800 stipends for researchers to ship equipment to the conference. The IEEE Robotics and Automation Society, in conjunction with the Committee for Medical Robotics, will cosponsor the conference, thereby providing years of organizational experience as well as a conduit for publicity. Consequently, the 4-6-page submitted papers will eventually be placed on IEEE Explore, a highly publicized website.

DESCRIPTION (provided by applicant): One of the most pervasive problems for stroke survivors is movement deficits. Recent research strongly supports prolonged practice of functionally-relevant activities of the upper limb, even though therapy time is quite limited by the current medical economic system. This grant focuses on new developments in human- robot interactions (haptics) that have revealed prospects in the areas of motor teaching and rehabilitation. Specialized robotic devices combined with computer-displays can tirelessly exert force, augment feedback, and redirect error in order to speed up, enhance, or trigger the motor relearning process. These approaches could extend and greatly enhance the recovery process. The first strategy that often comes to mind for teaching movements is to guide the limb along the desired path. However, a promising alternative approach is to make movements more difficult by deflecting them from the desired path. People develop, through practice, the ability to counteract forces that distort the mechanical world, and if these forces are properly designed and applied, a desired movement pattern occurs when the forces are eventually switched off. We and others have also obtained similar results by distorting the visual world using prisms or virtual reality displays. In these studies, the subject sees something unexpected that is perceived as an error. Our results point to a single unifying theory: Errors induce learning, and judicious error augmentation (through forces or visual distortions) can lead to lasting desired changes. Interestingly, this process appears to bypass conventional learning mechanisms that require intense concentration - results are the same if the subjects have a conversation or listen to music. They often consider it a game. Until now very little of this research has been functionally relevant because the devices'ranges of motion were small, were two dimensional, and were lacking an appropriate visual interface. Three dimensional movements introduce the daunting new challenge of gravitational effects that could reduce (or perhaps heighten) the potential of error augmentation training. Our lab has spent several years developing a large- workspace, three dimensional haptics/graphics system. The aims of this grant are to build on our promising body of evidence and expand our error augmentation training work to a large workspace in three dimensions. Accordingly, the experiments below further refine our understanding of error augmentation (Aim 1), expand our approaches to three dimensions (Aim 2), and then move towards clinical application by testing our approaches on stroke survivors (Aim 3).

DESCRIPTION (provided by applicant): Support of the 2010 EMBS conference, Buenos Aires, Argentina Summary The Engineering in Medicine and Biology Society (EMBS) will hold its annual conference (EMBC) at the Sheraton Hotel in Buenos Aires, Argentina from August 31 through September 4, 2010. It is expected that more than 1500 scientists, engineers and students will be attending this conference from all over the world. EMBS of the IEEE has been organizing annual conferences of the engineering in medicine and biology society for past 30 years. This has clearly become the flagship conference for the entire bioengineering discipline, bringing together international experts, industry representatives and students in many, diverse fields encompassing biomedical engineering. In keeping with our tradition, the EMBC Student Paper Competition (SPC) is indeed a critical portion of the conference that provides a forum for top-notch students to compete. Such a competition promotes education within bioengineering, encourages excellence, and spotlights prominent student work to the wider bioengineering community. It is believed that such a gathering of students is the best way to help launch careers of future leaders, as they witness and participate in the conference. Without the incentive of this Competition, many students would be unable or less likely to attend the conference, thus missing an introduction to the world of knowledge available at such conferences. In addition, the SPC plays a crucial role in recognizing the talents of women, minorities, and individuals with disability. This Competition promotes not only education within bioengineering disciplines, but fosters the next generation of bioengineers by providing a unique opportunity to students to meet and network with the leading biomedical professionals and scientists in the world. The overall goal of this proposal is to request support for the Student Paper Competition (SPC) for the 2010 EMBS International Conference. Our goals are to organize a competition amongst approximately 150-200 papers expected to be submitted to the SPC, and select up to 25 finalists, who will make highlighted oral presentations during the conference. Finalists will be selected based on the average score from written reviews (normally 2-3 reviews are obtained for each paper). During the Conference Review Process, the student's advisor must submit a nomination form for his/her student's paper to participate in the Competition. First, second, and third place winners will be selected based on the professionalism of the presentation, verbal communication skills, and the technical merit of the topic. Three SPC winners will receive an engraved plaque and an honorarium of US$1000 for the first place winner, US$750 for the second place winner, and US$500 for the third place winner. All Finalists will receive Certificates of Merit and will be recognized at the EMBS Awards Ceremony, with the appropriate acknowledgement of NIH sponsorship. Finalists will receive funds to defray the costs of travel expenses. The proposed funding will help student finalists to travel to present their research paper in the Student Paper Competition. It will also provide the cash prizes for the winners of the Competition and if funds remain, subsidize the attendance of junior faculty researchers. It is believed that such a gathering of students is the best way to help launch careers of future leaders with them witnessing and participating in the exemplary scientific and engineering behavior at the EMB conference. PUBLIC HEALTH RELEVANCE: Support of the 2010 EMBS conference, Buenos Aires, Argentina The Engineering in Medicine and Biology Society (EMBS) will hold its annual conference (EMBC) at the Sheraton Hotel in Buenos Aires, Argentina from August 31 through September 4, 2010. We request support for the Student Paper Competition (SPC), which we believe to be a most critical element of the conference. Our goals are to organize a competition amongst approximately 150-200 papers expected to be submitted to the SPC, and select up to 25 finalists, who will make highlighted oral presentations during the conference and will receive funds to defray the costs of travel expenses. It is believed that such a gathering of students is the best way to encourage attendance and help launch careers of these future leaders.

DESCRIPTION (provided by applicant): This study investigates the potential of customized robotic and visual feedback interaction to improve recovery of movements in stroke survivors. While therapists widely recognize that customization is critical to recovery, little is understood about how take advantage of statistical analysis tools to aid in the process of designing individualized training. Our approach first creates a model of a person's own unique movement deficits, and then creates a practice environment to correct these problems. Experiments will determine how the deficit-field approach can improve (1) reaching accuracy, (2) range of motion, and (3) activities of daily living. The findings will not only shed light on how to improve therapy for stroke survivors, it will test hypotheses about fundamental processes of practice and learning. This study will help us move closer to our long-term goal of clinically effective treatments using interactive devices.