Fedor Anna, Skollár Gabriella, Szerencsy Nóra, Ujhelyi Mária
Eötvös Loránd University of Sciences, Budapest, Hungary.
J Comp Psychol. 2008 Nov;122(4):403-17. doi: 10.1037/0735-7036.122.4.403.
Ten gibbons of various species (Symphalangus syndactylus, Hylobates lar, Nomascus gabriellae, and Nomascus leucogenys) were tested on object permanence tasks. Three identical wooden boxes, presented in a linear line, were used to hide pieces of food. The authors conducted single visible, single invisible, double invisible, and control displacements, in both random and nonrandom order. During invisible displacements, the experimenter hid the object in her hand before putting it into a box. The performance of gibbons was better than expected by chance in all the tests, except for the randomly ordered double displacement. However, individual analysis of performance showed great variability across subjects, and only 1 gibbon is assumed to have solved single visible and single invisible displacements without recourse to a strategy that the control test eliminated.
对10只不同种类的长臂猿（合趾猿、白掌长臂猿、黑冠长臂猿和白颊长臂猿）进行了客体永久性任务测试。使用三个相同的木箱，呈直线排列，用来隐藏食物块。作者以随机和非随机顺序进行了单次可见、单次不可见、双次不可见和对照位移实验。在不可见位移实验中，实验者先将物体藏在手中，然后再放入箱子。除了随机顺序的双次位移实验外，长臂猿在所有测试中的表现均优于随机水平。然而，个体表现分析显示，不同个体之间存在很大差异，只有1只长臂猿被认为在不借助对照测试所排除的策略的情况下，解决了单次可见和单次不可见位移问题。
