[Functional activity of the laryngeal motor neurons in the anesthetized cat]

The spontaneous activity of laryngeal motoneurons has been recorded in anesthetized cats. Laryngeal motoneurons were antidromically identified by their activation from the recurrent nerve. From the total number of recorded neurons, 80% showed an activity correlated with the inspiratory phase and 20% with the expiratory phase of the respiratory cycle. Within the limits of the antidromic field potential induced by the electrical stimulation of the recurrent nerve, the activity of inspiratory neurons not antidromically activated from the vagus or recurrent nerve, was also recorded. In the same area several efferent neurons activated from the vagus nerve, which showed spontaneous activities unrelated to the respiratory cycle were also recorded.