Exploring hypoglossal motoneuron behavior using dynamical systems analysis

Hypoglossal motoneurons (HMs) participate in a variety of upper airway behaviors, including but not limited to swallowing, breathing, suckling, speech, and maintaining upper airway patency. Because of this, the morphological and electrophysiological properties of HMs have been studied extensively in both neonatal and adult mammals. While a number of studies have identified changes in HM properties over a variety of developmental ages, the development of computational models has been limited to predominantly neonatal HMs. To overcome this limitation, we recently explored firing frequency dynamics via alterations to ion channels and calcium handling mechanisms in an attempt to capture behaviors exhibited in both in neonatal and more mature ( e.g. , juvenile, adult) HMs. While we found it possible to model a variety of behaviors through such methods, certain behaviors have remained elusive. Here, we apply dynamical systems analysis to better understand the behavior of HMs. Implementation of such methods allows us to elucidate the underlying properties governing spike shape, adaptation, and firing frequency, and enhances our ability to more fully observe the distinct behaviors identified experimentally. Supported by HL63175.