Speech communication involves the transmission of information from a talker to a listener. When deficiencies and imperfections occur in the biological, psychological or physical systems required for normal speech output, communicative speech disorders are manifested.Various professions are concerned with these speech communication failures in infants, children, adolescents, adults and the aged, and therefore diagnostic, therapeutic and research teams should include specially trained personnel from the professions of medicine, dentistry, physiology, psychology, nursing, physical and occupational therapy, linguistics, sociology, special education, engineering and others. Major contributions are being made by each profession and the cumulative impact of these contributions is providing the basic principles upon which are founded our most valid and reliable diagnostic and therapeutic procedures. In this presentation, the multidisciplinary approach will be considered as related to the basic areas of 1) prevention and 2) diagnosis.
A physiological experiment was carried out on six types of“placing the tone”by F. Husler (type No. 1 was abridged) with a forty-one years old tenor. The vowel used was“a”, and the vocal pitch was“f”in No. 2, 3a, 3b and“a'”in No. 4, 5, 6. The following items were analysed: 1) The vibration mode of the vocal cords (Fig. 1) and its opening and closing time rate (Tab. 1) as observed by ultra-high speed laryngocinematography. 2) The displacements of the larynx (Fig. 2, 3) and the diaphragm (Fig. 6) by X-ray cinematography. 3) The sound spectrum of the voice (Fig. 4) . 4) The air flow rate, the vocal intensity, the circumference of the chest and the abdomenn on four points were recorded polygraphically (Fig. 5) and mean values were estimated (Tab. 2) . The subject showed some difficulty in performing proper control of breathing for the type six.