Jitsumori M, Ohkubo O
Department of Cognitive and Information Sciences, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba-shi 263, Japan.
Behav Processes. 1996 Dec;38(3):205-26. doi: 10.1016/s0376-6357(96)00030-7.
In Experiment 1, pigeons trained to discriminate rightside-up and upside-down orientations of slides of natural scenes with humans successfully transferred to new slides of the same kind. Experiment 2 revealed that both the orientations of the human figures and of the background scenes controlled the discrimination. When they were oppositely oriented, the background orientation cue was dominant. In Experiment 3 slides showing objects on a white background were presented either rightside up or upside down, with each slide presented in one orientation only. One group of pigeons learned to classify the slides according to their orientations. The other group learned to classify the slides according to arbitrary groupings. When the slides were shown rotated by 180 degrees, the latter group continued to discriminate the individual slides (i.e., the pigeons showed orientation invariance). The former group classified the rotated slides according to their orientations (i.e., orientation discrimination). In Experiment 4, pigeons learned the orientation discrimination with separate sets of human and bird figures. Partial reversal training in one object class transferred to the rest of stimuli in this object class but did not to the other object class. These results suggest that pigeons can learn to discriminate photographs on the basis of orientation but that orientation-based equivalence relationship is not formed between object classes.
在实验1中，经过训练能够区分自然场景幻灯片正立和倒立方向的鸽子成功地将这种辨别能力迁移到了同类的新幻灯片上。实验2表明，人物的方向和背景场景的方向都能控制辨别。当它们的方向相反时，背景方向线索占主导地位。在实验3中，展示在白色背景上物体的幻灯片以正立或倒立的方式呈现，每张幻灯片只以一种方向呈现。一组鸽子学会根据幻灯片的方向对其进行分类。另一组鸽子学会根据任意分组对幻灯片进行分类。当幻灯片旋转180度展示时，后一组鸽子继续区分各个幻灯片（即鸽子表现出方向不变性）。前一组鸽子根据幻灯片的方向对旋转后的幻灯片进行分类（即方向辨别）。在实验4中，鸽子分别对人物和鸟类图形进行方向辨别学习。在一个物体类别中的部分反转训练迁移到了该物体类别的其他刺激上，但没有迁移到另一个物体类别上。这些结果表明，鸽子可以学会根据方向辨别照片，但在物体类别之间不会形成基于方向的等价关系。
