Functional organization of the central cough generation mechanism.
Recent studies evaluating the effects of pulmonary afferents, chemoreceptors, and antitussive drugs on the cough motor pattern indicate that this reflex is regulated in a different manner than breathing. Furthermore, regulatory differences exist between tracheobronchial and laryngeal cough. We propose a functional model of the brainstem elements participating in the production of cough that accounts for these regulatory differences. The model incorporates known brainstem interneuronal pathways as well as novel regulatory elements for tracheobronchial and laryngeal cough. Each of these novel regulatory elements controls the excitability of a common motor pattern generation network. Given that cough and breathing are associated with profoundly different spatiotemporal alterations in motor drive to respiratory motoneurons, brainstem elements common to the generation of both behaviours must be capable of a high degree of plasticity.