Effects of muscimol inactivations of functional domains in motor, premotor, and posterior parietal cortex on complex movements evoked by electrical stimulation.
Effects of muscimol inactivations of functional domains in motor, premotor, and posterior parietal cortex on complex movements evoked by electrical stimulation.
复制标题
运动、前运动和后顶叶皮层功能域的蝇蕈醇失活对电刺激引起的复杂运动的影响。
DOI：
10.1152/jn.00491.2013
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发表时间：
2014
影响因子：
2.5
通讯作者：
Kaas,JonH
中科院分区：
文献类型：
--
作者：
Stepniewska,Iwona;Gharbawie,OmarA;Burish,MarkJ;Kaas,JonH
顶叶和额叶皮质是控制前肢运动的中枢。我们之前的研究表明，当500毫秒的电脉冲通过微电极传递时，可以从主运动(M1)、运动前(PMC)和顶叶后(PPC)皮质诱发伸展、抓取和防御等运动。激发特定运动的刺激点聚集成区域，这在新大陆猴子和原猴星系中具有相同的地形模式。顶叶和额叶皮质中匹配的功能区优先相互连接。我们推测，匹配的功能域形成了参与特定运动的平行网络。为了测试结构域在M1、PMC和PPC中的作用，我们系统地用一个区域中的Muscimol结构域灭活，并确定其他区域中匹配的结构域是否发生功能变化。最常见的变化是刺激诱发运动的当前阈值较高，运动轨迹较短，但尚未完全发育。M1功能区的失活极大地减少或取消了PMC或PPC中从匹配域引起的运动，而从非匹配域引起的运动大多不受影响。相反，灭活PMC或PPC结构域并不会始终如一地取消从匹配的M1结构域唤起运动的能力。然而，PMC结构域的失活抑制或改变了从PPC结构域引起的运动。因此，由PMC引起的运动序列取决于M1，而从PPC引起的运动序列取决于M1和PMC两者。总体而言，结果支持PPC、PMC和M1被细分为功能域的结论，这些功能域在并行网络中具有层级关系。
Parietal and frontal cortex are central to controlling forelimb movements. We previously showed that movements such as reach, grasp, and defense can be evoked from primary motor (M1), premotor (PMC), and posterior parietal (PPC) cortex when 500-ms trains of electrical pulses are delivered via microelectrodes. Stimulation sites that evoked a specific movement clustered into domains, which shared a topographic pattern in New World monkeys and prosimian galagos. Matched functional domains in parietal and frontal cortex were preferentially interconnected. We reasoned that matched functional domains form parallel networks involved in specific movements. To test the roles of domains in M1, PMC, and PPC, we systematically inactivated with muscimol domains in one region and determined if functional changes occurred in matching domains in other regions. The most common changes were higher current thresholds for stimulation-evoked movements and shorter, not fully developed, trajectories of movements. Inactivations of an M1 functional domain greatly reduced or abolished movements evoked from the matching domains in PMC or PPC, whereas movements evoked from nonmatching domains remained mostly unaffected. In contrast, inactivating PMC or PPC domains did not consistently abolish the ability to evoke movements from matching M1 domains. However, inactivation of PMC domains suppressed or altered the movements evoked from PPC domains. Thus movement sequences evoked from PMC depend on M1 and movement sequences evoked from PPC depend on both M1 and PMC. Overall, the results support the conclusion that PPC, PMC, and M1 are subdivided into functional domains that are hierarchically related within parallel networks.