Functional organization of human posterior parietal cortex: grasping- and reaching-related activations relative to topographically organized cortex
Functional organization of human posterior parietal cortex: grasping- and reaching-related activations relative to topographically organized cortex
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DOI：
10.1152/jn.00657.2012
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发表时间：
2013-06-01
影响因子：
2.5
通讯作者：
Kastner, Sabine
中科院分区：
文献类型：
--
作者：
Konen, Christina S.;Mruczek, Ryan E. B.;Kastner, Sabine
伸手抓住物体的动作需要手臂的移动和手的形状之间的协调。猕猴和人类的神经生理学、神经影像学、神经解剖学和神经心理学研究表明，抓握和伸手行为背后的神经网络在后顶叶皮层（PPC）中至少部分是可分离的。为了更好地了解这些神经网络是如何在灵长类动物中进化的，我们使用功能性MRI描述了抓握和伸手相关反应与人类顶内沟（IPS）地形组织区域之间的关系。抓握特异性激活定位于左前IPS，与最前地形区域部分重叠，并延伸到中央后沟。到达特异性激活定位于左侧楔前叶和上级顶叶小叶，部分重叠的内侧方面更后方地形区域。虽然IPS的地形区域内的大部分活动是非特异性的运动类型，我们发现的证据达到和把握运动跨越后内侧到前外侧PPC的特异性功能梯度。与猕猴相反，抓握和到达特异性激活主要位于人类IPS之外。
The act of reaching to grasp an object requires the coordination between transporting the arm and shaping the hand. Neurophysiological, neuroimaging, neuroanatomic, and neuropsychological studies in macaque monkeys and humans suggest that the neural networks underlying grasping and reaching acts are at least partially separable within the posterior parietal cortex (PPC). To better understand how these neural networks have evolved in primates, we characterized the relationship between grasping- and reaching-related responses and topographically organized areas of the human intraparietal sulcus (IPS) using functional MRI. Grasping-specific activation was localized to the left anterior IPS, partially overlapping with the most anterior topographic regions and extending into the postcentral sulcus. Reaching-specific activation was localized to the left precuneus and superior parietal lobule, partially overlapping with the medial aspects of the more posterior topographic regions. Although the majority of activity within the topographic regions of the IPS was nonspecific with respect to movement type, we found evidence for a functional gradient of specificity for reaching and grasping movements spanning posterior-medial to anterior-lateral PPC. In contrast to the macaque monkey, grasp-and reach-specific activations were largely located outside of the human IPS.