雜音下に於ける純音聽力に就て

　Ⅰ．緒言

　雑音による遮蔽の下に於ける純音聽力の変化を諸種難聽の鑑別診断に用いる企ては，既にLaugenbeckその他によつて為されているが，私達も最近同樣の目的の下に諸種実験を試みる残会を得たので，成績の一部を発表して御批判を得たいと思う。

　TSUIKI and ARAI investigate the effect of noise in hearing pure tones. When the noise supplied is as much as 60 phon interference of pure tone hearing as shown in the audiogram follows closely that of the spectrum-curve. With difference-Limen Test hearing with and without the noise there was a decrease at least 10 db D.L.value with the former. When the external canal is sealed of with an ear-plug the hearing in presence of 60 phon noise is not affected in any way differing from that of the ear under normal condition similarly plugged.