Smirnova A A, Lazareva O F, Zorina Z A
Department of Higher Nervous Activity, Lomonosov State University, Moscow.
Zh Vyssh Nerv Deiat Im I P Pavlova. 1998 Sep-Oct;48(5):855-67.
Six hooded crows (Corvus cornix) were trained in alternative simultaneous matching-to-sample and oddity-from-sample tasks with visual stimuli. Bird's ability to acquire the abstract same/different concept was investigated. For this purpose three stimulus sets of the following categories were used: color (black and white cards), shape (Arabic numerals "1" and "2"), and numerousness (heterogeneous arrays of 1 or 2 elements). These three sets were used for training successively and repeatedly; each time the stimulus set was changed for the next one after the criterion (80% correct or better over 30 successive trials) was reached with the previous one. The training procedure was repeated until the criterion could be reached for each of the three stimulus sets within the initial 30-50 trials. After that, the abstractness of the rule acquired by birds was tested. First, the "partial" transfer tests were conducted, which consisted in presentation of novel stimuli with familiar ones (numerals and arrays in the range from 1 to 4). At the final stage, only sets of novel numerals and arrays in the range from 5 to 8 were presented. The crows demonstrated successful transfer in all of these tests, including the test with absolutely novel stimuli (in the first 24 presentations: min 75.0%, p < 0.02; max 83.3%, p < 0.01). The level of correct choices did not differ from the baseline (p > 0.05). This allows us to conclude that birds are capable for formation of the abstract same/different concept.
六只 hooded crows（Corvus cornix）接受了视觉刺激的交替同时匹配样本和样本异常任务训练。研究了鸟类获取抽象的相同/不同概念的能力。为此，使用了以下三类刺激集：颜色（黑白卡片）、形状（阿拉伯数字“1”和“2”）以及数量（1 或 2 个元素的异构阵列）。这三组刺激集依次反复使用；每次在前一组达到标准（连续 30 次试验中正确率达到 80%或更高）后，将刺激集更换为下一组。重复训练过程，直到在最初的 30 - 50 次试验内，这三组刺激集中的每一组都能达到标准。之后，测试鸟类所习得规则的抽象性。首先，进行“部分”迁移测试，即呈现新刺激与熟悉刺激（1 到 4 范围内的数字和阵列）。在最后阶段，仅呈现 从 5 到 8 范围内的新数字和阵列集。这些乌鸦在所有这些测试中都表现出成功的迁移，包括使用绝对新刺激的测试（在前 24 次呈现中：最低 75.0%，p < 0.02；最高 83.3%，p < 0.01）。正确选择的水平与基线无差异（p > 0.05）。这使我们能够得出结论，鸟类能够形成抽象的相同/不同概念。
