Intensity and fundamental frequency (Fo) of voice and air flow rate during phonation were simultaneously measured and displayed by means of a newly developed phonation function analyzer (PS-77, Nagashima Co.) consisting of a microphone, a hot-wire flow meter and a 3-channel pen recorder, Fo was derived from the flow meter through the filter system. Seventy six cases with various laryngeal diseases and 20 normal adults were exa-m fined in the present study. The subjects were required to hold a mouth-piece attached to the flow meter and sustain vowel /a/ in the following fashions; easy phonation, soft voice, loud voice, low-pitched voice, high-pitched voice and falsetto. In the normal subjects, Fo curve generally showed a flat contour indicating that Fo was kept constant during phonation. Intensity and flow rate curves also tended to stay flat with occasional fluctuations or decay. In pathological cases, the three curves showed various patterns some of which appeared to be characteristic for each disease. A comparison of the curves taken before and after the treatment was often indicative of the effectiveness of the treatment. It was considered that the analyzer could provide useful information for the follow-up study of laryngeal pathology, although it could not necessarily serve the purpose of differential diagnosis of laryngeal diseases.
Simultaneous measurements of pitch, intensity and air flow have been often carried out for estimation of dysphonias. As phonosurgery to restore normal voice is now popular, such a method for evaluation of voice is absolutely necessary like audiogram in the field of audiology. We have designed a very versatile and convenient device thanks to up-to-date development of electronics. By use of these instruments, further process like ratio of intensity and air flow or pitch perturbation to flow and intensity is available, and these results will give us an excellent information to laryngologists. On the other hand, it is very important to analyze the pattern itself obtained. We have analyzed simultaneous recordings in patients with polypoid vocal folds and stiff vocal folds including normal cases. Base on the results obtained, we concluded as follows; (1) In normal cases, intensity and flow lines in graphical record are almost flat. (2) In cases with polypoid vocal folds, their lines are gradually declined in course of phonation. (3) In cases with stiff vocal folds, their lines usually have notches. These results mentioned above are discussed mainly from the view point of phonodynamics.
In order to analyze hoarseness of the voice disorders, new phonation analyzer was used. The voice was put in a hot wire spirometer (MINATO IKA Co. LTD, Japan) and was memorized by a memory circuit. The date was visualized by an oscilloscope or pen writing recorder. The human voice was analyzed from viewpoints of the parameters of the intensity, pitch and mean flow rate. An oscilloscope, part of the apparatus, was enable to demonstrate the relationship between intensity-mean flow rate, pitch-mean flow rate and intensity-pitch dimentionally. For instance, the value was plotted as a brilliant spot in abscissa for intensity and in ordinate for mean flow rate via a feed back memory system. The examinee was vocalized /a: / by a mouth piece, and was spoken of a paragraph by a mask. The maximum sustained phonation time was measured automatically. Twenty adult female and ten adult male were volunteers, aged from twenty to forty eight. The curve in male which was demonstrated by intensity (abscissa) and mean flow rate (ordinate) was characteristic as a unique pattern compared with the one in female. Generally in male (normal subject), the mean flow rate was minimum in moderate intensity of speech range and was gradually increased from minimum intensity to maximum in order. Change in intensity-mean flow rate of female was not dynamic. After the normal pattern of each relationship among intensity, pitch and mean flow rate was decided, the voice disorders were checked and compared. A vocal cord polyp, a laryngeal nodule and recurrent laryngeal nerve palsy showed characteristic patterns.
A number of new parameters and new ways of display for evaluating the phonatory ability are proposed. A device has been developed to record the following three quantities simultaneously as a function of time (t) : fundamental frequency (F0), voice intensity (I), and airflow rate (U) . The aim of this paper is to find out those parameters that are most effective for the evaluation of phonation by positively using a number of quantities in combination. Firstly, parameter E' based on I and U representing a phonatory efficiency is proposed. Then, by using A, which is an alternative I normalized by F0, a revised efficiency E is proposed. E is more powerful than E' when the mode (register) change is expected. As concerns time (t), an example to suggest a possible significant relation between the decay slope of U and the intended vocal intensity is presented. Representing t in a logarithmic scale is also suggested. In this mode of representation, the data can be displayed compactly in one chart even for utterances whose durations differ by more than one order of t, and therefore it makes it easier for us to inspect the time change of phonatory ability.
To investigate the relationship between normal childhood disfluency and stuttering, various types of normal childhood disfluency were examined in relation to age and levels of sentence structure acquisition. The subjects were 50 nursery school children, aged 2 to 6, whose conversational utterances in play situation have been tape recorded and analyzed. The major findings were as follows: 1) Frequency of each type of disfluency tended to increase in children from 2 to 4 years old and to decrease in 5 and 6 years old children. 2) The percentages of children who used longer sentences and various types of sentences tended to increase in children from 2 to 4 years old. 3) The children using the greater number of different types of sentences showed the higher frequency of disf luency. 4) Increase and decrease of each type of disfluency showed similar tendency in relation to age and levels of sentence structure. Taken together, these results were interpreted to indicate that normal childhood disfluency tends to increase at a certain stage of language acquisition and then decrease afterwards.