Neurobiology of Breathing Control

Abstract

Control of breathing is the domain of the brain with its input sensors and output muscles. Understanding control is therefore a neurobiological problem first and foremost. The challenge is connecting the physiology of control, e.g., CO₂ response curves, to measurable properties of the brain. Movements, such as those that underlie (the control of) breathing, are the product of a finely tuned and coordinated pattern of motoneuronal activity, not the product of readily measurable properties, such as the firing rates of individual neurons. Neurobiologists have delineated many properties of the constituents of the brain: molecules, membranes, synapses and neurons, yet very little is known about how these properties underlie integrative behaviors like control of breathing. The difficulty lies in the unique topology of the brain. Neurons are highly interconnected, and although these connections can be grossly delineated, the rules they follow appear almost entirely ad hoc.