Publication Date


Document Type


Committee Members

F. Javier Alvarez-leefmans (Committee Member), Timothy Cope (Advisor), Kathrin Engisch (Committee Member), Robert Fyffe (Advisor), Courtney Sulentic (Committee Member)

Degree Name

Doctor of Philosophy (PhD)


Body and limb movements are controlled by regulating the activity of motor pools and their constituent motoneurons. An extensive complement of tightly regulated ion channels and second messenger systems determine active motoneuron spiking behavior, while segmental propriospinal circuits ensure the faithful execution of motor commands by providing real time sensory feedback to motoneurons and other somatosensory centers. However, current mechanistic understanding is incomplete for critical factor regulating motoneuron firing properties. Fundamental gaps in knowledge exist regarding (a) the spatial distribution and organization of specific ion channels in motoneurons, (b) the contribution of specific channels to motoneuron intrinsic properties, (c) the rules governing interactions between segmental interneuronal populations and motoneurons, and (d) patterns of motoneuron synaptic connectivity across flexor and extensor motor pools. Studies undertaken in this dissertation are aimed at filling several of these gaps in our current understanding of motoneuron behavior. Multiple factors that affect a-MN excitability and firing are examined, including select ion channels, intrinsic membrane properties, and synaptic inputs. In addition, one series of studies was undertaken to advance understanding how some of these factors respond to peripheral nerve injury.

Page Count


Department or Program

Biomedical Sciences

Year Degree Awarded


Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.