Physiology and Biophysics

April 16, 2020

Randall Powers Ph.D.

Research Professor

Ph.D. Physiology-Psychology
University of Washington, 1982

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Input-output properties of motoneurons

Motoneurons are the final common path for converting motor commands and peripheral afferent feedback into muscle contraction. There is normally a one-to-one relation between action potentials in motoneurons and those in the muscle fibers they innervate, making it possible to use intramuscular and surface electrodes to record motoneuron activity in behaving human subjects. I have been interested in how synaptic inputs and motoneuron properties shape motoneuron discharge for most of my scientific career and have investigated motoneuron input-output properties using intracellular recordings in reduced animal preparations, motor unit recordings in human subjects and computer simulations of motoneuron models. My ultimate goal is to develop accurate models of populations of motoneurons and their associated local inhibitory interneurons that will allow me to “reverse engineer” motoneuron discharge patterns, i.e., use the discharge of multiple motor units to infer the excitatory, inhibitory and neuromodulatory inputs that produced that activity.