ABSTRACT Many reaching actions involve both hands. An open question is whether two-handed reaching involves two simultaneous, independent unimanual reaches, or recruits additional or different processes than those mediating one-handed reaching. We tested optic ataxic patient MDK on a set of unimanual and bimanual reaching tasks. Although MDK was impaired in both types of reaching task, his bimanual reaching was considerably better than his unimanual reaching. These results imply that bimanual reaching involves different or additional processes relative to unimanual reaching. We suggest that bimanual reaching may involve monitoring of the distance between the two hands relative to the distance between the two targets.

中文翻译：

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双手视觉引导运动不仅仅是其各部分的总和：来自视神经失调的证据

摘要 许多伸手动作涉及双手。一个悬而未决的问题是，双手伸手是否涉及两个同时的、独立的单手伸手动作，或者比单手伸手动作需要更多或不同的过程。我们在一组单手和双手到达任务中测试了视神经共济失调患者 MDK。尽管 MDK 在两种类型的伸手任务中均受损，但他的双手伸手比单手伸手要好得多。这些结果意味着，与单手接触相比，双手接触涉及不同或额外的过程。我们建议双手到达可能涉及监测两只手之间的距离相对于两个目标之间的距离。