Author(s)

Saya Natsui^1*, Megumi Sato², Tomomi Yokoyama³, Hiromi Inaba⁴, Naomi Kuboyama⁵, Kenichi Shibuya⁴

¹Graduate School of Health and Welfare, Niigata University of Health and Welfare Graduate School, Niigata, Japan.
²RESCO Corporation, Tokyo, Japan.
³WELCIA YAKKYOKU CO., LTD., Niigata, Japan.
⁴Department of Health and Nutrition, Niigata University of Health and Welfare, Niigata, Japan.
⁵Osaka University of Commerce, Osaka, Japan.

The purpose of the present study was to examine the effect of the frequency of mastication on cerebral activation and task scores for computational tasks. Eleven healthy subjects participated in the present study (nine women, two men). Subjects carried out the Uchida-Kraepelin Test for 15 min before and after chewing tasteless gum for five minutes. The oxygenation of the left prefrontal cortex was monitored by near-infrared spectroscopy during the computational tasks. Task scores did not differ significantly according to chewing frequency (p > 0.05). Conversely, the oxygenation value measured after mastication at a chewing frequency of 110 times/minute (Hz) was significantly higher than that observed before mastication (p < 0.05). Meanwhile, before and after levels of oxygenation did not differ significantly for chewing frequencies of 30 Hz and 70 Hz (p > 0.05 for both). The results of the present study suggest that tasteless mastication does not enhance calculation performance, while a high mastication frequency demonstrates an influence on oxygenation. However, our study indicates that chewing tasteless gum per se does not increase cognitive performance.

Mastication, Frequency, Brain Activity, Uchida-Kraepelin Test, Near-Infrared Spectroscopy

Natsui, S. , Sato, M. , Yokoyama, T. , Inaba, H. , Kuboyama, N. and Shibuya, K. (2020) Effects of Chewing Frequency on Cerebral Blood Flow and Cognitive Function. Journal of Behavioral and Brain Science, 10, 287-295. doi: 10.4236/jbbs.2020.107018.