[Effect of transection of the forebrain, diencephalon and midbrain on respiration in cats]

In vagotomized cats, after removal of the brain portion 5 mm rostral to the visual nerves crossing, the eupnoea type of respiration was preserved. Transection in the area of the visual nerves crossing was followed by a stable acceleration of respiration. Starting from the level of the posterior border of the visual nerves crossing and more caudal, successive transections of the brain entailed sharp decrease in the breathing rate, increase of the respiratory volume, and complicated changes of the lungs ventilation.