日本語語音に依る聽力檢査の基礎

　耳鼻咽喉科領域に於ける当面の重要問題の一は聽力檢査であろう．從來の聽力檢査法に著しく不便であり多くの疑問を有することは周知の通りである．連続音叉に依る聽力檢査が多くの時間と労力を要し面倒であり，又誤差が入り易く從つて信頼度を高める爲めには熟練を要することは大きな欠点であると言える．然しそれにも増して考慮を要することは此の檢査法が純音のみに依るものであり．仮令「オーヂオメーター」使用により上記の欠点は或る程度補えるとは言え，吾人日常会話音声とは音響的に大きな相違があると言う事実である．

　次に咡語檢査法であるが現在行われているものに余りに簡單であり，此の程度の檢査では何等聽力に関する具体的な面は説明されないと思う．咡語は言語の面に於ては日常会話と同じであるが音響学的方面から観る時は，その性質に未だ不明な点もあるが有聲会話音とは相当に異つたものであり，從つて此の檢査法を以つて充分に尋常会話音に代用し得るとは決して言い得ないのである．

　Ozawa and Shimizu say that, from the standpoint of acoustics, there is a great difference when comparison is made between the means currently used in the present day hearing tests the pure tones and the whispered speech, on one hand, and the every day conversation, on the other. When the object of the test is to establish the patient's ability to hear every day conversation the most desirable method seems to be the use of every day speech in that test. In authors' attempt in search of appropriate word sounds for use in the testing the most practical material was found in the "logatom" table which is ordinarily used in testing speech transmittability on the telephone. To make such a chart complete various studies, such as of articulations, intelligibilities, frequencies and wave lengths, are made on consonants and vowels of Japanese speech as they occur. Considerations of these points are highly essential when constructing a "logatom talle" that might be used with adequacy in testing patients for hard of hearing as well as electronic hearing aids.