Department of Sports Dentistry, Tokyo Dental College, Nihon University School of Medicine, Tokyo, Japan.
Adv Exp Med Biol. 2010;662:485-90. doi: 10.1007/978-1-4419-1241-1_70.
The purpose of this study was to compare the influence of biting and finger clenching intensity on the concentration of oxygenated hemoglobin (OxyHb) in regional cerebral blood flow (rCBF) as an indicator of brain activity in the primary motor (MI) and somatosensory (SI) cortices. Functional near-infrared spectroscopy (fNIRS) was used in 8 healthy subjects. Subjects were required to do biting (bite) and finger clenching (fclench) at 20, 50 and 80% of maximum force. To minimize the effect of temporal muscle activity on the working side of the jaw, the fNIRS probes were positioned contralaterally, in the left temporal region. Activation of MI and SI cortices with bite and fclench was noted in all subjects, irrespective of the intensity of bite and fclench. A significant increase was observed in OxyHb in MI and SI between 20% and both 50 and 80% intensity. In MI cortex, OxyHb showed a significant increase between 80% and both 20 and 50% fclench intensity. The results suggest that intensity of bite and fclench influences activation levels in MI and SI. Further, an activation was more obvious with bite than fclench.
本研究旨在比较咬合力和手指紧握强度对局部脑血流（rCBF）中氧合血红蛋白（OxyHb）浓度的影响，OxyHb 作为大脑活动的指标，用于检测初级运动（MI）和体感（SI）皮质。该研究使用功能性近红外光谱（fNIRS）对 8 名健康受试者进行检测。要求受试者以最大力量的 20%、50%和 80%进行咬和手指紧握（fclench）。为了将咀嚼肌活动对下颌工作侧的影响最小化，fNIRS 探头放置在对侧，即左侧颞区。所有受试者均观察到咬和手指紧握会激活 MI 和 SI 皮质，而与咬和手指紧握的强度无关。在 MI 和 SI 中，OxyHb 在 20%至 50%和 80%强度之间均显著增加。在 MI 皮质中，OxyHb 在 80%至 20%和 50%的 fclench 强度之间显著增加。结果表明，咬合力和手指紧握强度会影响 MI 和 SI 的激活水平。此外，咬合力比手指紧握更能引起明显的激活。
