laboratory focuses on two main research questions. One is, how, and to what
extent, does the nervous system control protein expression in skeletal muscle
fibers? Whole muscle, single motor units and single muscle fibers are studies
physiologically and biochemically. Light and confocal microscopy including
quantitative enzyme analyses and immunofluorescent microscopy are some of the
experimental methods used to study motor unit plasticity. The principal animal
models used are spinal cord injury, spaceflight and surgically induced
compensatory hypertrophy. These studies have shown that although the nervous
system has a significant influence on the kind and amount of specific proteins
synthesized, there are factors intrinsic to individual fibers that also define
these properties. The results show also that the neural influence that is
associated with muscle fiber types is probably not mediated via the amount or
pattern of activity of the motor units. A second, general question is how the
neural networks in the lumbar spinal cord of mammals, including humans, control
stepping and how this stepping pattern becomes modified by chronically imposing
specific motor tasks on the limbs after complete spinal cord injury. Limb
motion, electromyographic and kinetic data are recorded to define locomotor
characteristics. These studies have shown that the mammalian spinal cord can
learn specific complex motor tasks such as standing and stepping. Considerable
effort is focused on integrating neural models of locomotion with actual
musculoskeletal properties that are subject specific. Another component of the
modeling tasks is to develop robotic devices that can quantify and assist
laboratory animals and humans with neuromuscular deficits to walk. A similar
device is being developed for use by crewmembers in maintaining a critical
level of control of locomotion in variable gravitational environments.
- Shah P.K., Gerasimenko Y., Shyu A., Lavrov I., Zhong H., Roy R.R., Edgerton V.R. “Variability in step training enhances locomotor recovery after a spinal cord injury.” Eur J Neurosci. 2012 Jul;36(1):2054-62.
- Hodgson J.A., Chi S.W., Yang J.P., Chen J.S., Edgerton V.R., Sinha S. “Finite element modeling of passive material influence on the deformation and force output of skeletal muscle.” J Mech Behav Biomed Mater. 2012 May;9:163-83.
- Kinugasa R., Hodgson J.A., Edgerton V.R., Sinha S., “Asymmetrical Deformation of Contracting Human Gastrocnemius Muscle,” J Appl Physiol. 2011 Dec 1. [Epub ahead of print]
- Shah P.K., Song J., Kim S., Zhong H., Roy R.R., Edgerton V.R., “Rodent estrous cycle response to incomplete spinal cord injury, surgical interventions, and locomotor training,” Behav Neurosci. 2011 Dec;125(6):996-1002.
- Edgerton V.R., Harkema S., “Epidural stimulation of the spinal cord in spinal cord injury: current status and future challenges,” Expert Rev Neurother. 2011 Oct;11(10):1351-3.
- Nandra M.S., Lavrov I.A., Edgerton V.R., Tai Y.C., “A PARYLENE-BASED MICROELECTRODE ARRAY IMPLANT FOR SPINAL CORD STIMULATION IN RATS.” Conf Proc IEEE Eng Med Biol Soc. 2011 Jan 23;2011:1007-10.
- Harkema S.J., Schmidt-Read M., Behrman A.L., Bratta A., Sisto S.A., Edgerton V.R., “Establishing the NeuroRecovery Network: Multisite Rehabilitation Centers That Provide Activity-Based Therapies and Assessments for Neurologic Disorders,” Arch Phys Med Rehabil. 2011 Jul 20. [Epub ahead of print]
- Harkema S.J., Schmidt-Read M., Lorenz D., Edgerton V.R., Behrman A.L., “Balance and Ambulation Improvements in Individuals With Chronic Incomplete Spinal Cord Injury Using Locomotor Training-Based Rehabilitation,” Arch Phys Med Rehabil. 2011 Jul 19. [Epub ahead of print]
- Musienko P., van den Brand R., Marzendorfer O., Roy R.R., Gerasimenko Y., Edgerton V.R., Courtine G., “Controlling specific locomotor behaviors through multidimensional monoaminergic modulation of spinal circuitries.” J Neurosci. 2011 Jun 22;31(25):9264-78.
- Harkema s., Gerasimenko Y., Hodes J., Burdick J., Angeli C., Chen Y., Ferreira C., Willhite A., Rejc E., Grossman R.G., Edgerton V.R., “Effect of epidural stimulation of the lumbosacral spinal cord on voluntary movement, standing, and assisted stepping after motor complete paraplegia: a case study,” Lancet. 2011 Jun 4;377(9781):1938-47. Epub 2011 May 19.