Dixon Peter, Glover Scott
Department of Psychology, University of Alberta, Edmonton, AB, T6G 2E9, Canada.
Royal Holloway University of London, Egham, UK.
Exp Brain Res. 2019 Jan;237(1):273-287. doi: 10.1007/s00221-018-5420-2. Epub 2018 Nov 2.
Understanding the differences between solo and joint action control is an important goal in psychology. The present study represented a novel approach in which participants performed a bimanual finger oscillation task, either alone or in pairs. It was hypothesized that performance of this task relies heavily on attention and utilizes two independent processes that differentially affect solo and joint performance. One process attempts to align the fingers correctly regardless of oscillation speed, and this is reflected in an alignment error evident even at slow oscillations. A second process attempts to minimize the time lag between the fingers as the oscillation speed increases, reflected in a temporal error indexed by the rate of error increase with increasing movement speed. In three experiments, alignment and temporal error in the finger oscillation task were compared in solo and joint actors. Overall, solo actors had much lower alignment error than joint actors. Solo actors also showed a reduction in temporal error when the fingers moved in a symmetrical rather than parallel fashion, consistent with previous research showing an increase in error with increasing movement speed. However, the effect of symmetry on temporal error did not occur with joint actors. Similar results were found with one hand inverted, suggesting that the pattern of results was not due to the use of homologous muscles. To test the role of visual feedback, we examined the effect of denying visual feedback to one of the actors in the joint condition. Paradoxically, under these conditions, there was lower temporal error in the symmetrical condition. These results are interpreted in terms of the organization of solo versus joint actions and the control of bimanual tasks in general.
理解单独行动控制与联合行动控制之间的差异是心理学的一个重要目标。本研究提出了一种新方法，即让参与者单独或成对地执行双手手指摆动任务。据推测，该任务的表现严重依赖注意力，并利用两个独立的过程，这两个过程对单独表现和联合表现有不同的影响。一个过程试图无论摆动速度如何都使手指正确对齐，这体现在即使在缓慢摆动时也明显存在的对齐误差中。第二个过程试图随着摆动速度的增加使手指之间的时间滞后最小化，这体现在一个由误差随运动速度增加的速率所索引的时间误差中。在三个实验中，比较了单独行动者和联合行动者在手指摆动任务中的对齐误差和时间误差。总体而言，单独行动者的对齐误差比联合行动者低得多。当手指以对称而非平行的方式移动时，单独行动者的时间误差也有所减少，这与先前研究表明误差随运动速度增加而增加的结果一致。然而，对称对联合行动者的时间误差没有影响。当一只手反转时也发现了类似的结果，这表明结果模式并非由于使用同源肌肉所致。为了测试视觉反馈的作用，我们研究了在联合条件下剥夺其中一个行动者视觉反馈的影响。矛盾的是，在这些条件下，对称条件下的时间误差更低。这些结果从单独行动与联合行动的组织以及一般双手任务的控制方面进行了解释。
