Music performance requires simultaneously producing challenging movement sequences with the left and right hand. A key question in bimanual motor control research is whether bimanual movements are produced by combining unimanual controllers or through a dedicated bimanual controller. Here, 34 expert pianists performed musical scale playing movements with the left or right hand alone and with both hands simultaneously. We found that for the left hand, scale playing was more variable when playing with both hands simultaneously rather than with one hand at a time, but for the right hand, performance was identical. This indicates that when task constraints are high, musicians prioritize timing accuracy in the right hand at the cost of detriment of performance in the left hand. We also found that individual differences in timing substantially overlap between the unimanual and bimanual condition, suggesting control policies are similar but not identical when playing with two hands or one. In the bimanual condition, the left-hand keystrokes tended to occur before right-hand ones, and more so when the hands were further apart. Performance of the two hands was furthermore coupled so that they tended to be early and late together, especially in the beginning and end of each scale. This suggests that experts are able to achieve tightly coupled timing of scale playing movements between the hands. Taken together, these findings show evidence for partially overlapping and partially separate controllers for bimanual and unimanual movements in piano playing.

中文翻译：

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一方面或另一方面：双手音乐音阶演奏中计时精度的权衡

音乐表演需要同时用左手和右手产生具有挑战性的动作序列。双手运动控制研究的一个关键问题是双手运动是通过组合单手控制器还是通过专用的双手控制器产生的。在这里，34 位专业钢琴家单独用左手或右手同时用双手演奏音阶演奏动作。我们发现，对于左手，同时用双手演奏而不是一次用一只手演奏时，音阶演奏的变化更大，但对于右手，性能是相同的。这表明当任务限制很高时，音乐家优先考虑右手的计时准确性，而牺牲左手的表现。我们还发现单手和双手条件下的个体差异在时间上有很大的重叠，这表明在用两只手或一只手玩时，控制策略相似但不完全相同。在双手条件下，左手击键往往先于右手击键，当双手分开时更是如此。两只手的表现进一步耦合，因此它们往往会一起早晚在一起，尤其是在每个音阶的开始和结束时。这表明专家能够在双手之间实现紧密耦合的音阶演奏时间。综上所述，这些发现显示了钢琴演奏中双手和单手动作部分重叠和部分分离的控制器的证据。建议在用两只手或一只手玩时控制策略相似但不相同。在双手条件下，左手击键往往先于右手击键，当双手分开时更是如此。两只手的表现进一步耦合，因此它们往往会一起早晚在一起，尤其是在每个音阶的开始和结束时。这表明专家能够在双手之间实现紧密耦合的音阶演奏时间。综上所述，这些发现显示了钢琴演奏中双手和单手动作部分重叠和部分分离的控制器的证据。建议在用两只手或一只手玩时控制策略相似但不相同。在双手条件下，左手击键往往先于右手击键，当双手分开时更是如此。两只手的表现进一步耦合，因此它们往往会一起早晚在一起，尤其是在每个音阶的开始和结束时。这表明专家能够在双手之间实现紧密耦合的音阶演奏时间。综上所述，这些发现显示了钢琴演奏中双手和单手动作的控制器部分重叠和部分分开的证据。当双手分开时更是如此。两只手的表现进一步耦合，因此它们往往会一起早晚在一起，尤其是在每个音阶的开始和结束时。这表明专家能够在双手之间实现紧密耦合的音阶演奏时间。综上所述，这些发现显示了钢琴演奏中双手和单手动作部分重叠和部分分离的控制器的证据。当双手分开时更是如此。两只手的表现进一步耦合，因此它们往往会一起早晚在一起，尤其是在每个音阶的开始和结束时。这表明专家能够在双手之间实现紧密耦合的音阶演奏时间。综上所述，这些发现显示了钢琴演奏中双手和单手动作部分重叠和部分分离的控制器的证据。