Selective paralysis of voluntary but not limbically influenced automatic respiration.

We describe a patient in whom a discrete infarction of the ventral basis pontis caused a complete loss of voluntary respiration, while automatic respiration remained intact. Respiratory excursions, quantified title volumes, and ventilatory response to carbon dioxide were normal, but the patient could not volitionally modify any respiratory parameters. Emotional stimuli producing laughter, crying, or anxiety appropriately modulated automatic respiration. This case established that pathways subserving limbic modulation of automatic respiration descend in the pontine tegmentum and/or lateral portion of the basis pontis spared by this lesion. Furthermore, descending limbic influences on automatic respiration are anatomically and functionally independent of the voluntary respiratory system.