Basic principles of control of breathing.

The metabolic demands of the body, including consumption of oxygen and removal of carbon dioxide, vary widely in health and disease. Ventilation must adjust to meet these demands and accommodate volitional and behavioral activities. Control of breathing depends on a complex and intricate feedback control system that integrates these automatic and volitional aspects of ventilation. Sensors, including chemoreceptors and lung volume receptors, relay information to a central controller located primarily in the medulla. The central controller integrates this information and determines the level of activation of the effectors (the respiratory motoneurons and muscles), which affects ventilation and gas exchange. Inputs from suprapontine structures, including the cerebral cortex, are also important in integrating volitional aspects of breathing into the control system.