Frequency Analysis System for Auditory Nerves with Auditory Brainstem Response (ABR) by Harmonious Tone
Hideto Ide and Masafumi Uchida
College of Science and Engineering Aoyama Gakuin University, 6-16-1 Chitosedai, Setagaya-ku, Tokyo, 157 Japan
Generally, sounds are composed of three parts, i.e., loudness, pitch, and tone color. The auditory system completes the frequency analysis of these components between peripheral nerve and medial geniculate body. Cerebrum cortex unite the result of analysis and past memories, and perform high level perceptional prudence. The system of frequency analysis has many unknown parts. If these parts are analyzed and explained, the comfort or discomfort to sounds and the human music sense can be clarified. In addition, it can be applied to medial and human engineering etc. As the new method of the system of frequency analysis between peripheral nerve and medical geniculates body, we investigated Auditory Brainstem Response (ABR). It was thought that generation was this communication process. ABR didn’t acknowledge the cerebrum cortex. We thought it was hard to effect drugs, sleep, physiology, or psychology. As the suitable sound for analyzing, we used ‘Chord’ (chord was, basic of the tone color.) thought which was common as a human inborn sense. The results were as follows: (1) In these ABRs, the high frequency components were low level. Background activities which were mainly low frequency components were conspicuous. (2) Alteration of short interval power spectrums exhibits a characteristic difference between harmonious tone and inharmonious, one at 40011z and 60011z. It seemed that the analysis of tone color is performed between peripheral nerve and medial geniculate body that were before cerebrum cortex.