Monday, April 27, 2015 (3:15 p.m. in Yost 306)
Title: Dynamics of Neurons and Field Potentials in the Auditory Brainstem
Speaker: Joshua Goldwyn (Visiting Assistant Professor, Ohio State University)
Abstract: Neurons in the medial superior olive (MSO) are temporally precise coincidence detectors that support our ability to localize sound sources. Questions persist regarding the precise workings of MSO neurons, in part because prominent sound-evoked extracellular field potentials hinder the acquisition of single cell in vivo data in the MSO. Using idealized, but biophysically-based neuron models, I will show how MSO neurons generate the distinctive spatio-temporal patterns of field potentials observed in experiments. An intriguing question is whether these extracellular potentials act as a form of non-synaptic coupling between nearby MSO neurons. I will demonstrate (using simulations) that millivolt-scale “in vivo-like” extracellular voltages can induce millivolt-scale changes in the membrane potential of an MSO model neuron and modulate its spiking output. In ongoing work, we are developing model-based methods that simultaneously fit extracellular recordings and infer putative excitatory and inhibitory currents that drive MSO neurons.
* This work is in collaboration with John Rinzel (New York University) and the Laboratory of Auditory Neurophysiology at the University of Leuven (director: Philip Joris)