Hiraba Hisao, Sato Takako
Department of Physiology, Nihon University School of Dentistry, Tokyo, Japan.
Somatosens Mot Res. 2005 Dec;22(4):307-17. doi: 10.1080/08990220500420525.
Mastication is achieved by cooperation among facial, masticatory, and lingual muscles. However, cortical control in cats for the masticatory performance is processed by two systems: facial movement processed by facial SI (the first somatosensory cortex), area C, and area M (motor areas), and jaw and tongue movements performed by intraoral SI, masticatory area, and area P (motor area). In particular, outputs from area P organized in the corticobulbar tract are projected bilaterally in the brainstem. In this present study, the aim is to explore changes in the regional cerebral blood flow (rCBF) in the facial SI, area M, and area P during trained lateral feeding (licking or chewing from the right or left side) of milk, fish paste, and small dry fish. The rCBF in area M showed contralateral dominance, and rCBF in area P during chewing or licking from the right or left side was almost the same value. Furthermore, activities of genioglossus and masseter muscles in the left side showed almost the same values during licking of milk and of fish paste, and chewing of small dry fish during lateral feeding. These findings suggest that the cortical process for facial, jaw, and tongue movements may be regulated by the contralateral dominance of area M and the bilateral one of area P.
咀嚼是由面部、咀嚼和舌肌共同协作完成的。然而，猫的咀嚼动作的皮质控制由两个系统处理：面部运动由面部第一体感皮层（SI）、C区和M区（运动区）处理，而颌骨和舌头的运动则由口内SI、咀嚼区和P区（运动区）执行。特别是，在皮质延髓束中组织的P区输出在脑干中双侧投射。在本研究中，目的是探索在训练后的侧向进食（从右侧或左侧舔食或咀嚼）牛奶、鱼酱和小干鱼期间，面部SI、M区和P区的局部脑血流量（rCBF）的变化。M区的rCBF表现为对侧优势，并且在从右侧或左侧咀嚼或舔食期间P区的rCBF几乎是相同的值。此外，在侧向进食期间舔食牛奶和鱼酱以及咀嚼小干鱼时，左侧颏舌肌和咬肌的活动表现出几乎相同的值。这些发现表明，面部、颌骨和舌头运动的皮质过程可能受M区的对侧优势和P区的双侧优势调节。
