Caljouw Simone R, van der Kamp John, Savelsbergh Geert J P
Institute for Fundamental and Clinical Human Movement Sciences, Vrije Universiteit Amsterdam, Van der Boechorststraat 9, the Netherlands.
Neurosci Lett. 2006 Jan 9;392(1-2):84-9. doi: 10.1016/j.neulet.2005.08.067. Epub 2005 Oct 17.
On the basis of research in self-paced aiming movements, Glover [S. Glover, Separate visual representations in the planning and control of action, Behav. Brain Sci., 27 (2004) 3-24] proposed a dichotomy between visual systems that accommodate planning and on-line control of action. Specifically, the planning-versus-control model posits that the on-line control system solely adjusts the spatial parameters of a movement. We examined whether this proposition is also adequate for interceptive hitting movements that require being at a specific location at the right time. Participants had to hit an approaching ball by first moving the bat away from the interception point (preparatory phase) and subsequently make the hitting movement (strike phase). The ball had to be projected to a landing location that could be near or far. To examine the ability of actors to use online visual information to adapt to unexpected changes in impact requirements, we perturbed the distance of the landing location from near to far during the unfolding of the movement. No adjustments were observed when the perturbation occurred at the onset of the strike phase. When the perturbation occurred at the onset of the preparatory phase the impact velocity increased and, therefore, the ball traveled a larger distance. This was realized by decreasing the duration of the strike phase and increasing the movement amplitude. So, both spatial and temporal characteristics of the hitting movement were adjusted to comply with an online perturbation of target distance. This observation is incongruent with Glover's recent proposition that the online visual system only accommodates spatial parameters.
基于对自定步速瞄准动作的研究，格洛弗[S. 格洛弗，《动作规划与控制中的独立视觉表征》，《行为与脑科学》，27卷（2004年）3 - 24页]提出了一种在适应动作规划和在线控制的视觉系统之间的二分法。具体而言，规划与控制模型假定在线控制系统仅调整动作的空间参数。我们研究了这一观点对于需要在正确时间到达特定位置的拦截击球动作是否也适用。参与者必须先将球棒从拦截点移开（准备阶段），然后进行击球动作（击球阶段）来击打飞来的球。球必须被击打到一个可能近或远的着陆位置。为了研究参与者利用在线视觉信息来适应撞击要求意外变化的能力，我们在动作进行过程中将着陆位置的距离从近扰动到远。当扰动在击球阶段开始时发生，未观察到调整。当扰动在准备阶段开始时发生，撞击速度增加，因此球飞行的距离更远。这是通过缩短击球阶段的持续时间并增加动作幅度来实现的。所以，击球动作的空间和时间特征都进行了调整，以适应目标距离的在线扰动。这一观察结果与格洛弗最近提出的在线视觉系统仅适应空间参数的观点不一致。
