Comparative cognitive studies on short-term memory in mandrill monkeys

对山魈（Mandrillus sphinx）的认知研究仍然很少。在这项研究中，我训练使用触摸屏显示器在京都城市动物园圈养的山魈。这些实验是对动物园游客开放的，目的是“展示智力”。参与者是两个成年人和三个青少年。我们通过逐次逼近训练触摸监视器，但幼年山魈通过观察学习自发地开始触摸监视器上的刺激。这一过程类似于黑猩猩婴儿的“师徒制教育”。山魈学会了阿拉伯数字序列。掌握序列后，用“掩码序列测试”测试幼年山魈的工作记忆。他们的表现在第二个项目上没有改变，尽管在触摸第一个项目后，下面的项目被掩盖了。结果表明，前两项有很大一部分是正确的。视觉偏好测试也进行了，但没有明确的结果。

There has still been few cognitive studies in mandrill monkeys (Mandrillus sphinx). In this study, I trained to use a touchscreen monitor in captive mandrills in Kyoto City Zoo. The experiments were conducted open to zoo visitors for "exhibition of intelligence". The participants were two adults and three juveniles. We trained to touch the monitor by successive approximation, but juvenile mandrills spontaneously started to touch stimuli on the monitor by observational learning. This processes were similar to those in chimpanzee infants called "education by master-apprenticeship". The mandrills learned sequence of Arabic numerals. After they mastered the sequence, the juvenile mandrills were tested working memory in "masked sequence test". Their performance did not changed at the second item although the following items were masked after touching the first item. The results suggest a chunk of the first two items. Visual preference test was also conducted, but showed no clear results.