Cluster Analysis of Neuronal Discharge Patterns During Breathing and the Laryngeal Adductor Reflex with Computer Simulations and Dynamic Visualizations

Abstract

The laryngeal adductor reflex (LAR) is a simple airway protective behavior that closes the vocal folds in response to mechanical or chemical stimulation of sensory afferents in the larynx. Previous work suggested that the intra‐medullary pathway that is responsible for activating laryngeal motoneurons is composed of as little as two synapses. We speculated that the central pathways supporting this behavior are more complex and involve neurons of several different phenotypes. Breathing and non‐breathing modulated neurons (n=632) were recorded with multiple electrode arrays in the ventral respiratory column (ventral respiratory group, pre‐Bötzinger, Bötzinger), pons, raphé, dorsal lateral medulla and spinal cord of decerebrate, paralyzed, vagus‐intact cats (n=13). The LAR was induced by electrical stimulation of the superior laryngeal nerve. We classified brainstem neuron activity phenotypes using a quantitative, reproducible clustering routine during baseline breathing and the LAR. We identified 25 breathing phenotypes that were mapped onto 16 LAR phenotypes. These results were used to produce a simplified model and simulations of the LAR. A 3‐D brainstem atlas displayed neuronal firing rates during periods of baseline breathing and/or the LAR, illuminated in proportion to firing rate. These data support distinct rather than a continuum of phenotypes based on discharge patterns during breathing as well as during the LAR.Support or Funding InformationSupport: OT2OD023854‐01, HL109025, HL131716This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.