Biophysical modeling to reverse engineer two mammalian neural circuits lower urinar Y tract and hippocampus
Abstract
Computational neuroscience provides tools to abstract and generalize principles of neuronal function using mathematics and computers. This dissertation reports biophysical modeling approaches to facilitate reverse engineering of two mammalian neural circuits - the lower urinary tract for the development of stimulation techniques, and the rodent hippocampus to understand mechanisms involved in theta rhythms. The LUT in mammals consists of the urinary bladder, external urethral sphincter (EUS) and the urethra. Control of the LUT is achieved via a neural circuit which integrates distinct components. Dysfunctions of the lower urinary tract (LUT) are caused by a variety of factors including spinal cord injury and diabetes. Our model builds on previous models by using biologically realistic spiking neurons to reproduce neural control of the LUT in both normal function and dysfunction cases. The hippocampus has long been implicated in memory storage and retrieval. Also, hippocampal theta oscillations (4-12 Hz) are consistently recorded during memory tasks and spatial navigation. Previous model revealed five distinct theta generators. The present study extends the work by probing deeper into the intrinsic theta mechanisms via characterizing the mechanisms as being resonant, i.e., inherently produce theta, or synchronizing, i.e., promote coordinated activity, or possibly both. The role of the neuromodulatory state is also investigated.
Degree
Ph. D.