Origins of manual preference and performance abilities in children and adults

用一只手来完成大多数非人工任务的偏好是一个有趣的人类特征。手偏好的一个值得注意的方面是，与其他任务相比，某些任务往往会引起更强的偏好和更大的首选手选择。同样，惯用手优势的大小在很大程度上取决于所研究的任务。然而，关于任务依赖的原因尚未达成共识，对手工偏好与绩效能力的发展过程的研究也很少。在我的实验室进行的研究试图更好地理解任务类型如何影响儿童和成人的手工偏好和表现能力。我们发现，有两个主要因素强烈偏好和表现能力：任务的精度要求和对象的特征，或对象的可视性。然而，任务类型如何影响儿童和成人的手工偏好和表现能力，在这些任务中注意力资源是如何分配的，以及运动方向是否是一个重要的调节变量，这些问题仍然存在。因此，在我的实验室之前进行的工作的基础上，目前的研究计划的目的是检查a)精度要求的作用；B)工具使用和对象可视性的作用；c)以身体为中心的运动在左撇子和右撇子（LH & RH）儿童和成人的手偏好和手表现中的作用；d)黄性系和RH型成人双手动作的注意分配；e)左、RH成人的语言偏侧化及运动方向对手部不对称的影响；f)任务特征如何影响特殊人群的手偏好和表现能力。由于大量的争议仍然围绕着手偏好和偏好手优势的起源问题，特别是两者的发展，对这些行为的决定因素的更仔细的检查将提供对两个半球神经专业化的见解。这项工作最终将有助于建立利手性和手工操作能力的发展理论模型。

The preference to perform most unimanual tasks with one hand is an intriguing human characteristic. One notable aspect of hand preference is that certain tasks tend to elicit stronger preferences and greater selection of the preferred hand than other tasks. Likewise, the magnitude of the preferred-hand advantage depends heavily on the task examined. However, no consensus has been reached on the reason for the task dependence, and little research has been conducted to examine the developmental course of manual preference and performance abilities. Research conducted in my laboratory has attempted to better understand how the type of task influences manual preference and performance abilities in both children and adults. We have found that there are two main factors that strongly preference and performance abilities: the precision requirements of the task and the object characteristics, or affordance of the object. However, questions remain concerning how the type of task influences manual preference and performance abilities in both children and adults, how attentional resources are allocated during these tasks, and whether movement direction is an important moderating variable. Therefore, building on the previous work conducted in my laboratory, the purpose of the current research proposal is to examine a) the role of precision requirements; b) the role of tool use and object affordances; and c) the role of body-centred movement in hand preference and hand performance in left- and right-handed (LH & RH) children and adults; d) the allocation of attention in bimanual hand performance in LH and RH adults; e) language lateralization and the effects of movement direction on manual asymmetries in LH and RH adults; and f) how task features influence hand preference and performance abilities in special populations. As a great deal of controversy still surrounds the issue of the origins of hand preference and the preferred-hand advantage, and in particular the development of both, closer examination of the determinants of these behaviours will provide insight into the neural specialization of the two hemispheres. This work will ultimately contribute to a developmental theoretical model of handedness and manual performance abilities.