Department of Experimental Psychology, University of Oxford, Oxford, UK.
Dev Med Child Neurol. 2013 Nov;55 Suppl 4:13-8. doi: 10.1111/dmcn.12300.
Some key stages in the development of manual actions have been discussed in this supplement based on the idea of the dorsal cortical stream as the pathway for translating visual information into action control. We argue that visual information, transmitted through specialized visuomotor dorsal-stream modules, is required in the control of manual actions for selecting and attending to the target object of the action, translating visual spatial information into motor programmes and planning a coordinated sequence of actions so as to reach an optimal end-state. In typical development, we illustrate dorsal-stream processing through results on the use of stereoscopic information to guide infants' reaches, and changes in target selection and detailed kinematics of reaches depending on age, object size, and reaching in darkness (when dorsal-stream information rapidly decays). We hypothesize 'dorsal-stream vulnerability' as a widespread feature of neurodevelopmental disorders, such as autism, Williams syndrome, and children born very preterm. Such deficits, identified as abnormal visuomanual actions, are seen in bimanual coordination, visual guidance of action in the 'postbox' task, and failures in motor planning for end-state comfort. We discuss the possible application of these approaches to a wider range of disorders including developmental coordination disorder.
本补充材料基于背侧皮质流将视觉信息转化为动作控制的途径这一观点，讨论了动作发展的一些关键阶段。我们认为，视觉信息通过专门的视动背侧流模块传输，对于控制手动动作以选择和关注动作的目标对象、将视觉空间信息转化为运动程序以及规划协调的动作序列以达到最佳终态是必需的。在典型的发展过程中，我们通过使用立体视觉信息来引导婴儿伸手的结果，以及根据年龄、目标大小和在黑暗中伸手（当背侧流信息迅速衰减时）来改变目标选择和伸手的详细运动学，来说明背侧流处理。我们假设“背侧流脆弱性”是神经发育障碍（如自闭症、威廉姆斯综合征和早产儿）的普遍特征。在双手协调、“邮箱”任务中动作的视觉引导以及终态舒适性的运动规划失败中，可以看到这些作为异常视动行为的缺陷。我们讨论了这些方法在包括发育性协调障碍在内的更广泛障碍中的可能应用。
