日本語母音の動態測定とアクセントの認識

Dr.J.V.Neustupny, Prague, says in his paper (the Bulletin of Phonetic Society of Japan No. 121, 1966) that if not for other reasons the almost generally accepted theory of pitch accent in the Tokyo dialect of Japan should be abondoned already because of the lack of any prove that intensity is really a nondistinctive feature. He also explains that both pitch and intensity are indispensable for the distinctive function of the free accent and both are its distinctive features. But, intensity does not seem to be dispensable for the free accent. I thought there may be some differences between pitch and sonority, and investigated the movement of pitch of every vowel in 125 words. The instrument I used is Sony P.T.-5 Taperecorder and Pen-oscillocorder, developed by Dr. Uemura, Head of Sony Laboratory. Its take-up reel turns around by the speed of 0.03 times and changes voice into visible waves which are written by heated pen on cardiograph paper. Pitch of the 125 words in both Tokyo and Osaka dialects accords with sonority except (A)(B)(C), explained below. (A) Words that have the accent on the voiceless first vowels : In that case, the second vowel shows the prominent type of falling pitch change. --Shown in Table 1, (6) [tsutoni] and (7) [kukan]. (B) The pitch movement above mentioned, can be adopted to explain the free accent, or delayed accent--' ososagari'. --the second vowel of (7) [kukan] (Osaka) in Table 1. The first vowels in the words of group (I) (Table 7, Fig. 1) are high pitched and intensive, while the second vowels in them are low and weak. The second vowel of (II) [kushi] becomes voiceless. As for the words in group (III), the first and the second vowels begin with almost the same pitch, and as for the words in group (IV), the vowels are lower and wealker than those of the second. And yet, the first vowels in all the words in Table 7 are acoustically high pitched. The pitch movement of the second vowels in the words of group (IV), are the same type of (6) [kukan] (Osaka). The first vowel of (67) [tsuke] is voiceless. (C) As for free accent or fastened accent, 'hayasagari', the vowel that begins to descend is not always "fall", but the descending pitch movement plays more important part. Table 7 tells that intensity has almost no relation to the accent. In both Tokyo and Osaka dialects, pitch and pitch movement only seem to be indispensable for the distinctive function of the accent. Some Japanese say that Tokyo dialect have stress accent but the truth is, I think, its accent is the pitched one just as in Osaka dialect, but in the former, pitch and intensity are interdependent. Intonation and prominence must be investigated as separate problems.