The effects of cerebellar stimulation or lesion on respiration

These studies examined the influence of the cerebellum on respiration in anesthetized cats. Electrical stimulation of the rostral fastigial nucleus (rFN) in spontaneously breathing cats produced respiratory changes that correlated positively with the pressor responses. Thirty-seconds of stimulation at low frequencies (50 Hz or less) increased the respiratory rate (f) at all active sites. At approximately half the sites, stimulation at higher frequencies elicited apnea. At the remaining sites, f increased at all stimulation frequencies. Inspiratory duration (T-j.) decreased, and mean inspiratory flow increased. Tidal volume (V™) was unaltered. Similar changes occurred when the pressor response was blocked by phenoxybenzamine.

In paralyzed animals, activity of the phrenic nerve served as an index of central respiratory activity. Results were similar, except that tidal neural activity (TNA; the neural correlate of V™) increased. In addition, minute neural activity (f x TNA) remained elevated for three minutes after stimulation.