Masticatory muscle EMGs and their self-control under stress loading in a vertical space

垂直空间应力加载下咀嚼肌肌电图及其自我控制

基本信息

批准号：
20592276
负责人：
FUJISAWA Masanori
金额：
$ 2.5万
依托单位：
Meikai University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2008
资助国家：
日本
起止时间：
2008 至 2010
项目状态：
已结题

项目摘要

It is known that there is a feedback-loop between the faculty of sight and posture control against gravity fluctuation (GF). However, the effect of masticatory muscle contraction on posture control is not well understood. We used 3-D motion pictures in a virtual space with GF, to examine changes in GF with different mandibular positions. Tooth contact positions included light clenching (LC) and mandibular rest position (RP).Five male volunteer subjects (mean age of 22.4 years old) with no history of temporomandibular disorders (TMD) were recruited. Subjects included students at Meikai University. Electromyograms (EMGs) from both sides of the masseter, tibialis anterior (TA) and gastrocnemius muscles (GM) were recorded with an active electrode unit. Subjects were asked to stand on a GF sensor board in the virtual space. EMGs and GF were recorded during the display of a 3-D "roller coaster" animation (80sec duration). Alternation of LC and RP was performed by each subject. Prior to the experiments, all the subjects were trained to maintain 10% of maximum voluntary contraction as controlled LC under visual EMG feedback. They were then asked to maintain this position at the beginning of the LC experiment. No tooth contact was required during the RP session. Integrated EMG values were analyzed fromthe time point when the most significant postural change associated with the display occurred. The area of GF was also analyzed to determine the relationship between body balance and LC.Except for R-GM, integrated EMG showed a significant increase under LC when compared with RP. The area of GF decreased significantly under LC when compared with RP which indicated well controlled body balance. Since tibialis anterior and gastrocnemius muscles were activated significantly more in regulating body balance under light clenching conditions than in the mandibular rest position, tooth contact could contribute to the postural regulation system.

众所周知，视觉能力和针对重力波动（GF）的姿势控制之间存在反馈回路。然而，咀嚼肌收缩对姿势控制的影响尚不清楚。我们在带有 GF 的虚拟空间中使用 3D 电影来检查不同下颌位置的 GF 变化。牙齿接触位置包括轻咬紧牙关（LC）和下颌休息位置（RP）。招募了 5 名无颞下颌疾病（TMD）病史的男性志愿者受试者（平均年龄 22.4 岁）。受试者包括明海大学的学生。使用有源电极单元记录两侧咬肌、胫骨前肌 (TA) 和腓肠肌 (GM) 的肌电图 (EMG)。受试者被要求站在虚拟空间中的 GF 传感器板上。在显示 3D“过山车”动画（持续时间 80 秒）期间记录 EMG 和 GF。每个受试者交替进行 LC 和 RP。在实验之前，所有受试者都接受了训练，以在视觉肌电图反馈下维持 10% 的最大自主收缩作为受控 LC。然后要求他们在 LC 实验开始时保持这个位置。 RP 过程中不需要牙齿接触。从与显示器相关的最显着的姿势变化发生的时间点开始分析积分肌电图值。还分析了 GF 面积以确定身体平衡与 LC 之间的关系。除 R-GM 外，与 RP 相比，LC 下的综合肌电图显示显着增加。与 RP 相比，LC 下的 GF 面积显着减少，表明身体平衡得到良好控制。由于在轻微咬紧牙关的情况下，胫骨前肌和腓肠肌在调节身体平衡方面比在下颌休息位置下更加活跃，因此牙齿接触可能有助于姿势调节系统。