Breathing control in neurological diseases.

Control of ventilation depends on a brainstem neuronal network that controls activity of the motor neurons innervating the respiratory muscles. This network includes the pontine respiratory group and the dorsal and ventral respiratory groups in the medulla, which contain neurons that fire primarily during inspiration, post-inspiration, or expiration. The ventral respiratory group includes the pre-Bötzinger complex, which contains neurokinin-1 receptor immunoreactive neurons critical for respiratory rhythmogenesis. Structural and degenerative disorders affecting this network produce abnormalities of respiration, including sleep apnea and various patterns of dysrhythmic breathing, not infrequently associated with disturbances of cardiovagal and sympathetic vasomotor control. This emphasizes the important interactions between the respiratory and cardiovascular control networks in the medulla. Common disorders associated with impaired cardiorespiratory control include brainstem stroke or compression, syringobulbia, Chiari malformation, high cervical spinal cord injuries, and multiple system atrophy. This review focuses on the functional organization of the respiratory control network and common causes of impaired control of respiration.