Modulation of the Mandibular Stretch Reflex Sensitivity During Various Phases of Rhythmic Open-Close Movements in Humans
Modulation of the Mandibular Stretch Reflex Sensitivity During Various Phases of Rhythmic Open-Close Movements in Humans
复制标题
人类节律开闭运动各个阶段下颌牵张反射敏感性的调节
DOI：
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
J. Abbink
中科院分区：
文献类型：
--
作者：
A. van der Bilt;Ea.M. Ottenhoff;H. W. van der Glas;F. Bosman;J. Abbink
下颌升降肌的肌梭向α运动神经元提供正反馈。一般认为，反馈在咀嚼期间被调制，使得在下颌张开期间可以避免下颌升降肌的反作用力。我们的目的是研究在人类开合运动的不同阶段，肌梭输入到α运动神经元的调制。为此，受试者以自然咀嚼频率进行有节奏的开合运动。意外地施加了力脉冲（5 N，10 ms），引发了下颌反射。在一个开闭周期中，在8个不同的相位对下颌骨施加脉冲，但每个周期仅1个脉冲。在3个无脉冲周期和3个有脉冲周期中记录两侧咬肌和颞肌的下颌运动和表面肌电图。为了研究下颌牵张反射灵敏度的调制是否取决于食物阻力，我们在下颌骨上施加了额外的外力，抵消了每个周期的下颌闭合。以随机顺序进行两个实验阶段，即，在不用力的情况下和在20 N的附加力的情况下。我们观察到明显的反射，在开始的下巴关闭，在关闭阶段，并在闭塞。无或只有微弱的颌反射，目前在下巴打开。当有外力作用时，咬合反射振幅较大。这种反射幅度的增加可能是由于γ运动神经元活动的调整，运动前抑制，或两者兼而有之。下颌闭合时引起的反射幅度与运动的相位无关。
The muscle spindles of the jaw elevator muscles provide positive feedback to the alpha motoneurons. It is generally assumed that the feedback is modulated during chewing so that counterproductive forces of the jaw elevator muscles can be avoided during jaw opening. Our aim was to investigate the modulation of the muscle spindle input to the alpha motoneurons during various phases of open-close movements in man. To that end, subjects made rhythmic open-close movements at their natural chewing frequency. A force impulse (5 N, 10 ms), eliciting a jaw-jerk reflex, was unexpectedly applied. The impulse was applied to the mandible at 8 different phases during an open-close cycle, but only 1 impulse per cycle. Jaw movement and surface EMG of the masseter and temporal muscles on both sides were recorded during 3 cycles without an impulse and 3 succeeding cycles with an impulse. To examine whether the modulation of the mandibular stretch reflex sensitivity depends on the food resistance, we applied an additional external force on the mandible, counteracting closing of the jaw each cycle. Two experimental sessions were performed in random order, i.e., without force and with an additional force of 20 N. We observed pronounced reflexes at the onset of jaw closing, during the closing phase, and at occlusion. No or only weak jaw-jerk reflexes were present during jaw opening. The reflex amplitudes at occlusion were larger when an external force was present. This increase in reflex amplitude may be the result of an adjusted gamma motoneuron activity, from pre-motor inhibition, or from both. The reflex amplitudes elicited during jaw closing were not correlated with the phase of the movement.
豚鼠皮质诱导的节律性下颌运动期间下颌运动与三叉神经运动神经元膜电位波动之间的关系。
影响因子：
2.5
作者：
Goldberg,LJ;Chandler,SH;Tal,M
通讯作者：
Tal,M