Doctor of Philosophy in Applied Physiology
In the
School of Biological Sciences
Adam De Boef
Will defend his dissertation
Mechanisms and Control of Widespread Spinally Mediated Inhibition
7th April 2023
1:30pm
In person: Applied Physiology Building, Room 1253, 555 14th St NW, Atlanta, Ga. 30318
https://gatech.zoom.us/j/3879995674
Thesis Advisor:
Richard Nichols, Ph.D.
School of Biological Sciences
Georgia Institute of Technology
Committee Members:
Timothy Cope, Ph.D.
School of Biological Sciences
Georgia Institute of Technology
Boris Prilutsky, Ph.D.
School of Biological Sciences
Georgia Institute of Technology
Dena Howland, Ph.D.
Dept. of Neurological Surgery and
Anatomical Sciences and Neurobiology
University of Louisville
Mark Lyle, Ph.D.
Division of Physical Therapy
ABSTRACT:
Proprioceptive feedback plays a crucial role in motor control. Proprioceptive feedback allows muscles to interact with one another, through excitatory and inhibitory pathways. Historically, there is a debate about the extent to which each proprioceptor contributes to intermuscular interactions. Furthermore, the regulation of this inhibitory network is poorly understood. Previous work from our lab suggested they are mediated by the force sensitive (Ib) pathways alone. However, synaptic connections within the spinal cord suggest the connections should be mediated by a combined length and force contribution.
Previous work from our lab demonstrates that incomplete spinal cord injuries (iSCI) disrupt inhibitory network between muscles. Utilizing three different iSCI models, the proprioceptive sources of intermuscular inhibition, and the descending control of the corresponding interneuronal network, were investigated. This project provides evidence that the group II afferents contribute to intermuscular inhibition and become over expressed after iSCI. These results provide new insights into the physiological function of force and length receptors projecting to the spinal cord. In addition, the results indicate that the medullary reticulospinal pathway regulates the structure of inhibition across the feline hindlimb, adding to the understanding of the role of this pathway in the regulation of posture and limb mechanics.
]]>