I. RESPIRATORY RESPONSES TO ACOUSTIC STIMULATION IN INTACT AND DECEREBRATE ANIMALS

Abstract

Sounds of known wave form, frequency and duration, produced by an electric oscillator, were used to stimulate intact and decerebrate bullfrogs (Rana catesbiana), intact rabbits, cats and dogs, and decerebrate rabbits. An alarm clock bell was used occasionally as the stimulus. In both intact and decerebrate frogs, prolonged oscillator tones caused a decrease in respiratory rate, while short, repeated tones or the sound of an alarm clock bell caused increase in rate. In the mammals used, acoustic stimulation of any kind caused an increase in respiratory rate. This effect was observed in decerebrate rabbits as well as in the intact forms. Reference to the phylogenesis of the bulbar structures shows that among the most primitive connections of the auditory nerve are those involving the visceral centers in the reticular formation. The acoustic-respiratory reflex remains independent of cerebral connections through the continued functioning of these early established bulbar pathways.