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There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
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Charles J. Heckman, PhD
Physiology, Physical Medicine and Rehabilitation
Physical Therapy and Human Movement Sciences
Northwestern University Feinberg School of Medicine
Abstract
Motoneurons are unique in being the only neurons in the CNS whose firing patterns can be easily recorded in humans, but only recently has it become possible to simultaneously record the firing patterns of many motoneurons via array electrodes placed on the skin. These population firing patterns contain detailed information about the synaptic organization of motor commands. It is now well established that motor commands consist of three components, excitation, inhibition and neuromodulation; the importance of the third component had become increasingly evident. Firing parameters linked to each of these three components will be considered, along with discussion of their limitations. Our recent efforts to develop a quantitative "reverse engineering" approach to estimate both the amplitudes and temporal patterns of inputs to motoneurons will also be presented. Taken together, these analyses have the potential to transform our understanding of the structure of human motor commands in both normal and pathological states.
About the Speaker
Dr. Heckman's lab has worked on the mechanisms of spinal motor output for over 25 years. Motoneurons provide the output to muscle for all movements and his systematic studies of these cells provide a fundamental underpinning for understanding motor function and its rehabilitation. The techniques in his lab span the cellular, circuit and system levels in animal preparations and the resulting data has allowed him to achieve remarkably deep insights in motor function in human subjects. His development of biologically realistic computer simulations of motoneurons synthesizes this multi-level information and provides both predictions to guide experiments in humans and a deeper understanding of cellular mechanisms of human function, with an emphasis on developing new therapies for spinal injury, ALS and cerebral stroke.
Physiology Brownbag Seminars
The Physiology Group in the School of Biological Sciences hosts Brownbag Lunchtime Seminars twice a month on Wednesdays at noon in room 1253 of the Applied Physiology Building located at 555 14th Street NW, Atlanta, GA 30318. You are welcome to bring a lunch and join us as we ruminate with us on topics in Physiology! A full listing of seminars can be found at http://pwp.gatech.edu/bmmc/seminars/.
