Multi-tasking in movement sequence learning - the role of the control mode, coding and the sequence representation

在某些情况下，人们能够在执行另一项任务的同时执行一个动作序列，例如驾驶汽车和进行对话。然而，在其他情况下，当另一个任务同时运行时，很难执行一个序列，例如写购物清单和进行对话。一个具有挑战性的问题是，为什么在某些情况下，顺序行为可以在多任务情况下执行，而在其他情况下则不能。更详细地看一下驾驶的例子就会发现，驾驶汽车涉及到一系列间歇性的行为选择。有些时候，司机正在进行对话，他/她可能会产生预先计划好的序列，而不是选择新的序列。在心理科学文献中，Pashler（1992）提出，在这个时间窗口期间，中枢认知过程的结构和功能限制（例如瓶颈）有可能被释放出来，同时执行其他任务。这也符合运动控制和学习文献中提出的计划和控制模型。根据这个模型，规划系统的目标是选择和启动一个适当的运动程序来达到运动目标。规划还决定了运动序列的初始运动学参数化，包括时间和速度。完成规划过程后再执行二次任务，不会造成双任务干扰。多任务另一个有趣的特点与规划之间的相互作用和两个不同维度的任务之间的联系有关。例如，一个三级跳远运动员口头上用“跳-跳-跳”来支持他/她的跳跃顺序。在这种情况下，不同的模式（语言/运动）支持序列的学习。如果两个任务一致地组合在一起，则两个任务将被链接。有趣的理论问题是确定不同任务的共变程度，以及这种联系是否将成为规划过程的一部分。在三个实验系列中，我们将研究这些关于多任务处理的问题。

In some situations people are able to perform a movement sequence while performing another task at the same time, for example driving a car and carrying on a conversation. However, in other situations it is difficult to perform a sequence while another task is running simultaneously, for example writing the grocery list and carrying on a conversation. A challenging question is to know why in some situations sequential behavior can be performed in multi-task situations and in other situations not. A more detailed view at the driving example shows that driving a car involves a selection of actions intermittently. Some of the time the driver is having a conversation, he/she is may be producing pre-planned sequences rather than choosing new ones. In the psychological science literature Pashler (1992) proposed that during this time window it is possible that the structural and functional limitations of the central cognitive processes (e.g. the bottleneck) are freed up to perform other tasks simultaneously. This is also in accordance with the planning and control model proposed in the motor control and learning literature. According to this model the goal of the planning system is to select and to initiate an appropriate motor program to reach the movement goals. Planning also determines the initial kinematic parameterization of the movement sequence including timing and velocity. Performing a secondary task after finishing the planning process will not result in dual-task interference. Another interesting feature of multi-tasking is related to the question of the interaction between planning and the linkage between two tasks of different dimensions. For example, a triple jump athlete verbally supports the sequence of his/her jump by 'hop-step-jump'. In this case different modalities (verbal/motor) support the learning of the sequence. If the two tasks are consistently combined, both tasks will be linked. The interesting theoretical question is to determine, to which degree the different tasks co-vary and if the linkage will be a part of the planning process. In three experimental series these questions on multi-tasking will be investigated.