Experiments on the peculiar region and threshold of oppressive or vibratory sensation caused by low-frequency pure tones

The oppressive or vibratory sensation caused by low-frequency sound is a widely known sensation inherent to that type of sound. In previous studies using one-third octave band noise as stimuli, the frequency region that causes the oppressive or vibratory sensation was felt before other sensations such as loudness and noisiness (here, called the peculiar region). However, it has been suggested that level fluctuations of one-third octave band noise affect the oppressive or vibratory sensation. Furthermore, few studies have investigated the threshold of these sensations. In the present study, we conducted laboratory experiments to investigate the peculiar region from 10 to 160 Hz as well as the sensation threshold by using low-frequency pure tones. The peculiar region in which the oppressive or vibratory sensation became dominant was generally consistent with the findings of previous studies. However, differences were found in relatively higher frequencies such as 80 and 160 Hz. In addition, the median threshold value was lower than the lowest level of the peculiar region. The threshold differed greatly among the participants, and the higher the frequency, the more pronounced the difference. Multiple regression analysis suggested that these individual differences might be related to noise sensitivity.