study. The subject was chosen as typical of a group of six soprano voices methods. METHOD

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1 254 J. Physiol. (I937) 9I, I2.784 THE MECHANISM OF PITCH CHANGE IN THE VOICE BY R. CURRY Phonetics Laboratory, King's College, Neweastle-on-Tyne (Received 9 August 1937) THE object of the work described in this paper was to study the action of the laryngeal mechanism in sopranos. For this purpose radiographs were made of a mesial, sagittal section of the head from the level of the nasal cavity to the larynx, while the subject was singing the vowel [a]. An analysis of the sound wave-form was made simultaneously with both a cathode ray oscillograph and a sound-on-disc record of the voice. If required, a motion picture recorded the subject's facial expression and the dimensions of the oral cavity could be determined by palatographic methods. METHOD For this study the X-ray apparatus used was a 10 kva. Muller tube mounted horizontally. The exposure was reduced to I sec. at 150 ma. with 80 kv. Each exposure was made on one-half of an 8 x 10 in. film and the moment of exposure controlled by a technique devised by the author [1937]. By this means the exposure could be made at any desired interval after the subject had attained the desired pitch, volume and quality. The subject's head was 12-8 cm. in width and the target was placed at 64 cm. distance from the tip of the nose. Hence the conical enlargement of the image was kept to 10 p.c. The cathode-ray oscillograph recorded on standard orthochromatic cine film run at 2 m./sec. with a time mark of 600 cycles. The microphone and amplifier for the oscillograph had an overall frequency response of + 2 db. from 100 to 8000 cycles. A synchronized sound-on-disc record was made of each study. The subject was chosen as typical of a group of six soprano voices which were studied. She was of American parentage, had had 3 years' training and had a good soprano voice covering the range from 208 to

MECHANISM OF PITCH CHANGE IN THE VOICE 255 1024 cycles. She was of small build and stature and had a small larynx.

2 MECHANISM OF PITCH CHANGE IN THE VOICE cycles. She was of small build and stature and had a small larynx. During the study she was seated in order to keep the cheek against the vertical casette, but no head-fixing harness was used. Every effort was made to put her at ease and she was apparently little disturbed by the method. She sang with a narrow jaw opening and the volume was not loud. After the study the acoustic record was played to a jury of observers who gave an analysis of the voice and vowel qualities. The illustrations were made from contact prints of the negatives and for reproduction it was necessary to outline the important lines of the tongue, palate, pharynx, etc. The median line is always indicated as a solid line while the outlines of recessed parts such as the edges of the tongue are indicated by dotted lines. On each figure the oscillogram is mounted in the top, left corner, with the phonetic analysis of the sound and the pitch of the voice below. Below that again the index letter of the subject and the number of the radiograph are given. The cervical vertebrae are identified and the distance between the right edge of the oscillogram and the mark on the upper lip represents 10 cm. measured along the median line of the singer's body. RESULTS The jury commented on the acoustic record as follows. In Fig. 1 the subject sang down a third and the voice was weak and throaty. In Fig. 2 the voice was still hoarse but the volume increased. In Figs. 3, 4, 5 and 6 the voice was a good soprano and the volume was good. In Fig. 7 the voice was shrill with a slight vibrato and the vowel quality was weakened. In Fig. 8 the voice was very shrill with little characteristic vowel nature. In the table the cavity dimensions and changes in position of the speech organs are analysed. All the measurements are relative to the positions shown in Fig. 1, and represent closely the actual dimensions on the singer's body. The effect of rising pitch on the width of the lip opening and jaw aperture is very noticeable. This may result from the technique of voice training, despite the fact that the subject sang with a close mouth opening. It may result also from increased tension in the genio-hyoid muscle, which elevates the hyoid but lowers the mandible also. Tension in this muscle may be sensed by touching the underside of the chin during the phonation of high-pitched sounds. The total movement of the head is small and for this reason the changes in position of the hyoid bone and longitudinal cartilages are even more noticeable. The lip opening corresponds closely to the jaw opening and there is no protrusion of the lips from sphincteric action of the lip muscles. Throughout the study there is

256 R. CURRY no indication of opening by the velar passage into the nasal cavity, though, as shown in Fig. 8, the uvula may change position during the course of the very rapid exposure.

3 256 R. CURRY no indication of opening by the velar passage into the nasal cavity, though, as shown in Fig. 8, the uvula may change position during the course of the very rapid exposure. The changes in shape of the uvula may indicate tension and relaxation. The sound records gave no indication of nasality for any of the vowels. The tongue positions for the vowel remain relatively constant. Transverse concavity of the tongue appears characteristic of singers and may be produced by contraction of the styloglossus muscle which retracts the tongue and elevates the sides. Transverse concavity of the anterior dorsum occurs when the tongue is retracted in the mouth. For the vowel in question it seems that such a humping-back of the tongue in the mouth and narrowing of the pharyngeal cavity are characteristic factors. This fact is inconsistent with the theory of wide pharyngeal opening in singing. Other radiographs made by the author show that a wide pharyngeal cavity is not strictly necessary for the production of loud tones, and in one case the subject produced a powerful tone with a cavity opening of about 4 mm. In the present study the subject tended to keep the tip of the tongue behind the lower teeth in accordance with the technique of voice training. The aperture at the laryngeal vestibule was never more than 4 mm. and often as little as 2 mm. It is interesting that the narrowest such opening occurred on the lowest and highest pitches, thus confirming the findings of laryngo-periscopic studies. The present series of radiographs shows that such laryngo-periscopic studies are possible only when the epiglottis can be kept up out of the way. Accordingly, it is obvious that the X-rays give information about the physiology of human speech in a way that would be impossible by other means. Throughout the study the most noticeable fact was the upward movement of the hyoid bone and the longitudinal cartilages relative to the cervical vertebrae as the pitch was raised. Furthermore, for the highest pitches the larynx was drawn up closer to the hyoid bone. The upward movement of the hyoid bone was accompanied by a forward movement indicating contraction of the genio-hyoid, the mylo-hyoid and the digastric muscles. The measurements in the table onp. 258 indicate that thisforward movement of the hyoid bone is partly checked bythe antagonistic pull of the laryngeal muscles under tension. In Figs. 3, 4 and 5 the forward movement was checked and the hyoid bone did not change position relative to the lower jaw. This progressive upward movement of the larynx must involve increasing tension in the internal laryngeal muscles, including the vocal cords. This increasing tension may result in the narrowing of the larynx ventricle vertically and in a closer approximation of the ventricular bands

4 THE JOURNAL OF PHYSIOLOGY, VOL. 91, No. 3 PLATE I Fig. 1. J Fig. 2. To facep. 256

5 PLATE II THE JOURNAL OF PHYSIOLOGY, VOL. 91, No. 3 Fig. 3. Fig. 4.

6 THE JOURNAL OF PHYSIOLOGY, VOL. 91, No. 3 PLATE III... Fig. 5. Fig. 6.

7 PLATE IV THE JOURNAL OF PHYSIOLOGY, VOL. 91, No. 3 Fig. 7. Fig. 8.

8 MECHANISM OF PITCH CHANGE IN THE VOICE 257 to the vocal cords. It would appear, however, that the mechanism of pitch change in the voice involves not merely tension of the vocal cords but also bodily upward movement of the whole larynx. SUMMARY A series of eight radiographs, depicting a mesial, sagittal section of the head from the nasal cavity to the larynx, is presented for the study of pitch change in a soprano voice singing the vowel [a] over the range from 208 to 1024 cycles. Simultaneous cathode-ray oscillograms and sound-on-disc records were made. The dimensions of the speech cavities and positions of the speech organs are given in tabular form on p. 258 and the following results are demonstrated. 1. The jaw and lip opening increases with rising pitch presumably as a result of voice training. 2. The position of the tongue is characteristic of the vowel. 3. The pharynx opening and aperture at the larynx vestibule are consistently narrow and the narrowest larynx openings occur on the lowest and highest pitches. 4. A progressive upward movement ofthe hyoid bone and longitudinal cartilages corresponds to the rising pitch. This upward movement amounts to 18 mm. over the range of more than two octaves. 5. The rising pitch results in a narrowing of the larynx ventricle vertically and a closer approximation of the ventricular bands to the vocal cords. The work was carried out during the author's,tenure of a Commonwealth Fund Fellowship in Speech at Ohio State University, U.S.A. The author would like to acknowledge his great indebtedness to Prof. V. A. Ketcham, Prof. G. Oscar Russell and to Dr J. C. Cotton for encouragement and direction, to Dean M cpherson and the Graduate Council for the provision of apparatus, and to teachers and students of the Department of Music who gave valuable information and acted as subjects for this study. REFERENCE Curry, R. (1937). Rev. sci. Instr. 8, 382.

9 258 R. CURRY Figures Vowel Pitch in cycles/sec. Jaw opening in mm. Lip opening in mm. Pharynx opening in mm. Head tilt to spine in degrees Upward movement of hyoid in mm. Forward movement of hyoid in mm. Aperture of the larynx in mm. DESCRIPTION OF PLATES I-IV a a a a a a a a Upward movement of larynx in mm. Concavity oftongue in mm Oral cavity opening in mm Movement of lower jaw in mm.

Place and Manner of Articulation Sounds in English. Dr. Bushra Ni ma

Place and Manner of Articulation Sounds in English Dr. Bushra Ni ma Organs of Speech Respiratory System Phonatory System Articulatory System Lungs Muscles of the chest Trachea Larynx Pharynx Lips Teeth