Department of Psychology, College of the Holy Cross, 1 College Street, P.O. Box 75A, Worcester, MA 01610, USA.
Anim Cogn. 2012 Sep;15(5):1021-30. doi: 10.1007/s10071-012-0511-0. Epub 2012 May 11.
This experiment examined the performance of common marmosets (Callithrix jacchus) on a series of patterned string problems to assess the marmosets' understanding of means-ends relationships. One marmoset, Jet, was exposed to a series of problems that were ordered in terms of perceived difficulty during two testings that were separated by 1 year. In the second testing, Jet received problems that had been used during the first testing along with three new problems. Each of the new problems was designed to be an exemplar of the type of problem that Jet had experienced difficulty with in the first testing. A second marmoset, Peaches, was tested on the same set of problems given to Jet in the second testing. Results indicated that the marmosets' performance on these problems fell into three categories. In one category, some problems were solved without evidence of trial-and-error learning. In a second category, there were problems in which the marmosets responded at chance levels initially but evidenced improvement as a function of extended testing. In a third category, some problems appeared to be virtually unsolvable even with extended testing. Taken together, these results indicate that the marmosets were able to learn the means-ends connection between pulling a string and obtaining food. This learning was best characterized as a trial-and-error process for some problem forms, while for others there appeared to be rapid learning that did not require extensive practice. The instances of rapid learning may be the result of the application of a simple spatial proximity rule in which the marmosets chose the string that was closest to an imaginary line drawn between the marmoset and the reinforcer.
本实验检验了普通狨猴（Callithrix jacchus）在一系列模式化绳索问题上的表现，以评估狨猴对手段-目的关系的理解。一只名为 Jet 的狨猴在两次测试中分别接受了一系列按照感知难度排序的问题，两次测试之间间隔 1 年。在第二次测试中，Jet 接受了在第一次测试中使用过的问题以及三个新问题。每个新问题都是为了代表 Jet 在第一次测试中遇到困难的问题类型而设计的。另一只名为 Peaches 的狨猴在第二次测试中接受了与 Jet 相同的问题集的测试。结果表明，这些问题的表现分为三类。在第一类中，有些问题无需试错学习即可解决。在第二类中，有些问题最初是随机反应，但随着测试的延长，反应有所改善。在第三类中，有些问题即使经过长时间测试似乎也几乎无法解决。总的来说，这些结果表明，狨猴能够学习到拉动绳子和获得食物之间的手段-目的联系。这种学习最好被描述为某些问题形式的试错过程，而对于其他问题，似乎存在不需要大量练习的快速学习。快速学习的实例可能是狨猴应用简单空间接近规则的结果，根据该规则，狨猴选择与自己和奖励之间画的假想线最接近的绳子。
