Role of the medial parieto-occipital cortex in the control of reaching and grasping movements
Role of the medial parieto-occipital cortex in the control of reaching and grasping movements
复制标题
DOI：
10.1007/s00221-003-1589-z
复制
发表时间：
2003-11-01
影响因子：
2
通讯作者：
Fattori, P
中科院分区：
文献类型：
--
作者：
Galletti, C;Kutz, DF;Fattori, P
内侧顶枕叶皮质是背内侧视觉流的中心节点。最近的生理学研究表明，猕猴的内侧顶枕叶皮层包含两个区域，视觉区V6和视觉区V6 A。V6区是一个视网膜定位组织的视觉区，直接从V1接收形状和运动信息，并与背侧视觉流的其他区域（包括V6 A）紧密相连。V6 A区是一个双峰视觉/体感区，它阐述了视觉信息，如形状，运动和空间，适用于控制伸手和抓握运动。V6 A的躯体感觉和骨骼运动活动影响上肢，并涉及到达和抓握运动的运输阶段。最后，V6 A与控制手臂运动的背侧运动前皮层有着强烈的联系。从这些数据中得出的结论是，内侧顶枕叶皮层在视觉引导下控制近端和远端运动的能力很强。与这一观点一致，猴的选择性V6 A病变在视觉引导运动中与病变对侧的手臂产生误触和误抓。这些缺陷与在视性共济失调患者中观察到的缺陷相似，表明人和猴的上级顶叶小叶是同源结构，视性共济失调综合征是“人类”V6 A区病变的结果。
The medial parieto-occipital cortex is a central node in the dorsomedial visual stream. Recent physiological studies in the macaque monkey have demonstrated that the medial parieto-occipital cortex contains two areas, the visual area V6 and the visuomotor area V6A. Area V6 is a retinotopically organized visual area that receives form and motion information directly from V1 and is heavily connected with the other areas of the dorsal visual stream, including V6A. Area V6A is a bimodal visual/somatosensory area that elaborates visual information such as form, motion and space suitable for the control of both reaching and grasping movements. Somatosensory and skeletomotor activities in V6A affect the upper limbs and involve both the transport phase of reaching and grasping movements. Finally, V6A is strongly and reciprocally connected with the dorsal premotor cortex controlling arm movements. The picture emerging from these data is that the medial parieto-occipital cortex is well equipped to control both proximal and distal movements in the online visuomotor guidance of prehension. In agreement with this view, selective V6A lesions in monkey produce misreaching and misgrasping with the arm contralateral to the lesion in visually guided movements. These deficits are similar to those observed in optic ataxia patients and suggest that human and monkey superior parietal lobules are homologous structures, and that optic ataxia syndrome is the result of the lesion of a 'human' area V6A.