Mechanism of Speech

Abstract

Past experiments have been confined mostly to an examination of the recorded speech curves or of speech phenomena after the sound emits from the vocal passages. And the physiological cause was imagined. Various conflicting vowel theories have resulted.A new method of attack has been carried out in the present investigation. Wheatstone harmonic or Willis cavity tone (erroneously called Helmholtz) theories are checked upon by direct physiological processes. Not only the forms but the exact dimensions of the speech cavities have been ascertained by means of X-rays, palatograms and larnygoperiskopik measurements, made simultaneously and instantaneously so that exact measurements of the vocal tract resonators are had in three planes making it possible to reconstruct these cavities with a high degree of accuracy. By attaching an artificial glottis to the model it should be theoretically possible to reproduce the vowel if the total air volume functioning as a resonator were responsible for vowel quality. I am sorry to have to admit however that although 116 different types of reeds and other sound stimuli were used for such a purpose, the results were negative. All vowel cavities gave sounds which were much alike and but poor imitations of the original, just as are all other mechanical imitations of human speech which we have heard.