Study of cerebral cortical mechanisms possibly responsible for jaw-movement disorders

电刺激初级躯体感觉皮层和前额叶皮层（岛叶皮层）的外侧部分以及无颗粒皮层的外侧部分引起的下颌运动是特定的皮质位置刺激。 然而，刺激无颗粒皮质的内侧部分不会引起任何下颌运动。 这些皮质区发出直接投射到三叉神经感觉核复合体和三叉神经运动核周围的网状结构，这两者都包括兴奋性和/或抑制性前运动神经元。 这些结果可能表明，从大脑皮质区通过三叉神经前运动神经元向三叉神经运动核的几个间接投射参与了特征性下颌运动的诱导，下颌运动障碍是由于大脑皮质区间接投射系统的障碍。

Electrical stimulation of the primary somatosensory cortex and the lateral part of the prefrontal cortex (insular cortex) as well as the lateral part of the agranular cortex induced jaw-movements which are specific for the cortical location stimulated. However, stimulation of the medial part of the agranular cortex did not induce any jaw-movements. These cortical areas sent direct projections to the trigeminal sensory nuclear complex and the reticular formation around the trigeminal motor nucleus both of which include excitatory and/or inhibitory premotoneurons. Note that such premotoneurons were also found in the solitary tract nucleus.These results may indicate that several indirect projections from the cerebral cortical areas to the trigeminal motor nucleus via its premotoneurons are involved in the induction of the characteristic jaw-movements, and the jaw-movement disorders are attributed to the disorders of the indirect projection systems from the cerebral cortical areas.