Bogale Bezawork Afework, Sugita Shoei
Laboratory of Function and Morphology, Department of Animal Science, Faculty of Agriculture, Utsunomiya University, 350 Minemachi, Utsunomiya, Tochigi, 321-8505, Japan.
Anim Cogn. 2014 Jan;17(1):105-11. doi: 10.1007/s10071-013-0642-y. Epub 2013 Jun 1.
We investigated whether jungle crows can learn concepts by using printouts of shapes in a simultaneous two-alternative task. Jungle crows were first trained with a red triangle and red square until they reached the discrimination criterion (80% of correct choices in two blocks of 10 trials each). Then, we tested crows with successive transfer tests to investigate both the discrimination cues being used and concept formation ability, by using novel triangular and non-triangular stimuli. All of the jungle crows learnt to discriminate between the triangle and square during training. The discrimination performance was generally not affected either by changes in the colour of the stimuli or when both shape and colour cues conflicted, with the previously non-rewarded shape but matching colour (red square) versus rewarded shape but non-matching colour (green triangle). The use of only outlines of the familiar stimuli also did not affect discrimination behaviour of crows. In addition, crows significantly discriminated novel triangular shapes during the limited trials given, suggesting their ability to form the concept of triangularity. However, failure to discriminate when the novel stimuli size deviated from the original suggests that there is a limit to shape concept formation in a familiar-novel context in the jungle crow.
我们研究了丛林鸦能否在同时进行的二选一任务中通过使用形状打印件来学习概念。首先用红色三角形和红色正方形对丛林鸦进行训练，直到它们达到辨别标准（在每个包含10次试验的两个组块中，正确选择达到80%）。然后，我们通过使用新颖的三角形和非三角形刺激，对乌鸦进行连续的转移测试，以研究它们所使用的辨别线索和概念形成能力。所有丛林鸦在训练期间都学会了区分三角形和正方形。辨别表现一般不受刺激颜色变化的影响，也不受形状和颜色线索冲突的影响，即之前未得到奖励的形状但颜色匹配（红色正方形）与得到奖励的形状但颜色不匹配（绿色三角形）。仅使用熟悉刺激的轮廓也不影响乌鸦的辨别行为。此外，在给定的有限试验中，乌鸦能显著区分新颖的三角形形状，这表明它们具有形成三角形概念的能力。然而，当新颖刺激的大小与原始刺激不同时，乌鸦无法进行辨别，这表明在熟悉-新颖情境中，丛林鸦的形状概念形成存在局限性。
