Department of Physical Therapy, Federal University of São Carlos São Carlos, Brazil ; Human Motor Systems Laboratory, Biodynamics of Human Movement, University of São Paulo São Paulo, Brazil.
Human Motor Systems Laboratory, Biodynamics of Human Movement, University of São Paulo São Paulo, Brazil.
Front Psychol. 2014 Dec 4;5:1406. doi: 10.3389/fpsyg.2014.01406. eCollection 2014.
In this study we investigated the effect of use of the non-preferred left hand to practice different motor tasks on manual preference in children and adults. Manual preference was evaluated before, immediately after and 20 days following practice. Evaluation was made with tasks of distinct levels of complexity requiring reaching and manipulation of cards at different eccentricities in the workspace. Results showed that left hand use in adults induced increased preference of that hand at the central position when performing the simple task, while left hand use by the children induced increased preference of the left hand at the rightmost positions in the performance of the complex task. These effects were retained over the rest period following practice. Kinematic analysis showed that left hand use during practice did not lead to modification of intermanual performance asymmetry. These results indicate that modulation of manual preference was a consequence of higher frequency of use of the left hand during practice rather than of change in motor performance. Findings presented here support the conceptualization that confidence on successful performance when using a particular limb generates a bias in hand selection, which diffuses over distinct motor tasks.
在这项研究中，我们调查了在儿童和成人中使用非优势左手进行不同运动任务练习对手动偏好的影响。在练习之前、之后立即和 20 天后评估了手动偏好。评估使用需要在工作空间中不同偏心度处到达和操作卡片的具有不同复杂程度的任务进行。结果表明，成年人使用左手会在执行简单任务时增加对该手在中央位置的偏好，而儿童使用左手会在执行复杂任务时增加对最右侧位置的左手偏好。这些效果在练习后的休息期间得以保留。运动学分析表明，在练习过程中使用左手不会导致手间表现不对称性的改变。这些结果表明，手动偏好的调节是由于在练习过程中左手使用频率增加，而不是运动表现的改变所致。本研究结果支持这样一种概念，即当使用特定肢体时成功表现的信心会产生对手选择的偏向，这种偏向会在不同的运动任务中扩散。
