Jason G W
Exp Neurol. 1983 Jul;81(1):114-25. doi: 10.1016/0014-4886(83)90161-9.
Studies of the effects of lesions of the parietal cortex suggest that this region plays a critical role in visuomotor guidance, whereas experiments on the effects of disconnecting this region from visual input have been inconsistent in supporting this hypothesis. In the present experiment, monkeys with a unilateral occipital lobectomy and splenial transection initially showed marked misreaching by the hand contralateral to the lobectomy when tested informally with peanuts presented by hand. Although this severe misreaching recovered within a few weeks, there was a persistent deficit in the contralateral hand on two, more difficult, reaching tasks. One task allowed full vision of the reaching hand; the other limited vision by requiring the monkeys to reach under an opaque shelf. Misreaching persisted on these tasks for at least 200 days after surgery. Monkeys with only an occipital lobectomy did not show contralateral-hand misreaching on informal testing or on the limited-vision task, and only very minor misreaching in two of three animals on the full-vision task. Results indicate that geniculostriate visual information must reach posterior cortical regions for visually guided reaching by the contralateral limb to be fully accurate.
对顶叶皮质损伤影响的研究表明，该区域在视觉运动引导中起关键作用，而关于将该区域与视觉输入断开连接的影响的实验，在支持这一假设方面并不一致。在本实验中，单侧枕叶切除和胼胝体横断的猴子，最初在对手持花生进行非正式测试时，切除侧对侧的手表现出明显的误抓。尽管这种严重的误抓在几周内恢复，但在两项更困难的伸手任务中，对侧手仍存在持续的缺陷。一项任务能让猴子完全看到伸手的手；另一项任务则通过要求猴子在不透明架子下伸手来限制视觉。术后至少200天，这些任务中的误抓情况持续存在。仅进行枕叶切除的猴子在非正式测试或有限视觉任务中未表现出对侧手误抓，在全视觉任务中，三只猴子中只有两只出现非常轻微的误抓。结果表明，膝状体纹状视觉信息必须到达后皮质区域，对侧肢体的视觉引导伸手才能完全准确。
