Regaiolli Barbara, Spiezio Caterina, Hopkins William D
Research and Conservation Department, Parco Natura Viva - Garda Zoological Park, Bussolengo (VR), Italy.
Neuroscience Institute and Language Research Center, Georgia State University, Atlanta, Georgia.
Am J Primatol. 2018 Mar;80(3):e22745. doi: 10.1002/ajp.22745. Epub 2018 Feb 19.
The presence of group-level handedness in non-human primates remains controversial, as different studies have produced inconsistent results. Bimanual coordinated tasks have been found to elicit more pronounced hand preferences than simple unimanual tasks. The aim of this study was to examine manual lateralization in a group of 15 Barbary macaques during unimanual and bimanual tasks. In the unimanual task, data on simple food reaching in a foraging context were collected. During the bimanual task, macaques had to use one hand to hold a tube-shaped apparatus while reaching with the other hand to retrieve the food inside it. Data on the hand use to retrieve food were collected. First, no significant group-level hand preference was found for the unimanual task. However, a significant right hand bias was evident for the bimanual task. At the individual-level, approximately 47% and 67% of the subjects had a significant hand preference in the unimanual and bimanual task respectively. The strength of the hand preference was greater in the bimanual than in the unimanual task. Findings of this study add Macaca sylvanus to the other species showing a right hand preference for coordinated bimanual tasks. Moreover, our results add to the growing body of evidence that bimanual tasks are more suitable and valid measures to investigate handedness in non-human primates.
非人类灵长类动物群体层面的用手习惯是否存在仍存在争议，因为不同的研究得出了不一致的结果。人们发现，与简单的单手任务相比，双手协调任务会引发更明显的用手偏好。本研究的目的是在15只巴巴里猕猴执行单手和双手任务时，研究其手动偏侧化情况。在单手任务中，收集了在觅食情境下简单获取食物的数据。在双手任务中，猕猴必须用一只手握住管状器具，同时用另一只手去够取里面的食物，并收集了用于获取食物的手的数据。首先，在单手任务中未发现显著的群体层面的用手偏好。然而，在双手任务中明显存在显著的右手偏向。在个体层面，分别约有47%和67%的受试者在单手和双手任务中有显著的用手偏好。双手任务中用手偏好的强度大于单手任务。本研究的结果将地中海猕猴加入到了其他对协调双手任务表现出右手偏好的物种中。此外，我们的结果进一步证明了双手任务是研究非人类灵长类动物用手习惯更合适、更有效的方法，这一证据越来越多。
