The role of visual information in control of a constrained locomotor task.
The role of visual information in control of a constrained locomotor task.
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视觉信息在控制受限运动任务中的作用。
DOI：
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发表时间：
1988
影响因子：
1.4
通讯作者：
J. Thomson
中科院分区：
文献类型：
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作者：
M. Laurent;J. Thomson
在一项实验中，受试者必须在不同的条件下步行到目标位置，这项实验考察了视觉引导运动的性质。目标距离被操纵，因此受试者必须(A)延长他们的步幅以击中目标；(B)缩短他们的步幅；(C)根本不调整他们的标准步长。他们在四种视觉条件下这样做：(A)正常视力；(B)每次要放在目标上的脚落在地上时，视觉被限制为“快照”；(C)每次要放在目标上的脚处于摆动阶段时都要快照；以及(D)离开目标后没有视觉。结果表明，受试者在大多数情况下都能成功地达到目标。然而，他们的动作的流畅性和流动性在不同的条件下有很大的不同。在正常视觉下，或当指向脚在地面时提供视觉快照时，当受试者接近目标时，运动被平稳地调节。如果快照是在指向脚处于摆动阶段时交付的，监管就变得笨拙和不协调。如果在接近过程中根本没有愿景可用，就会进行调整，但这些调整是最不协调的。结果表明，协调良好的视觉调节不需要连续的视觉指导，而是依赖于动作序列中适当时间的间歇性信息。这样的时机往往比可用于指导的信息总量更重要。
The nature of visually guided locomotion was examined in an experiment where subjects had to walk to targets under various conditions. Target distance was manipulated so that subjects had to (a) lengthen their paces in order to hit the target; (b) shorten their paces; (c) make no adjustments to their standard pace length at all. They did this under four visual conditions: (a) normal vision; (b) with vision restricted to a "snapshot" each time the foot that was to be placed on the target was on the ground; (c) with a snapshot each time the foot to be placed was in the swing phase; and (d) no vision after departure fro the target. The results show that the subjects succeed in reaching the target in most cases. However, the smoothness and fluidity of their movements vary significantly between conditions. Under normal vision or where visual snapshots are delivered when the pointing foot is on the ground, locomotion is smoothly regulated as the subjects approach the target. where snapshots are delivered when the pointing foot is in the swing phase, regulation becomes clumsy and ill coordinated. Where no vision is available at all during the approach, adjustments are made, but these are least coordinated of all. The results show that well-coordinated visual regulation does not require continuous visual guidance but depends on intermittent information being available at the appropriate times in the action sequence. Such timing is often more important than the total amount of information that is available for guidance.