Tokai University, School of Marine Science and Technology, 3-20-1 Orido, Shimizu, 424-8610, Shizuoka, Japan.
Kamogawa Sea World, 1464-18, Higashi-machi, Kamogawa, 296-0041, Chiba, Japan.
Sci Rep. 2017 Aug 30;7(1):9914. doi: 10.1038/s41598-017-09925-4.
Beluga whales use calls to convey various information to group members. Is this communication similar to humans? We addressed this question by using the framework of stimulus equivalence. Stimulus equivalence consists of three phases: if the animal is trained to match A to B and B to C, symmetry is demonstrated by matching BA and CB, transitivity by matching AC, and equivalence by matching CA. We tested the spontaneous establishment of cross-modal stimulus equivalence between visual and auditory symbols in a beluga whale nicknamed Nack. Nack could make symmetrical choices in novel objects untrained. Moreover, visual/auditory cross-modal transitivity was formed spontaneously. Nack succeeded in six tasks, including an untrained task concerning stimulus equivalence. We conclude that Nack spontaneously formed cross-modal stimulus equivalence between visual and auditory symbols. Cross-modal stimulus equivalence was considered to exist only in humans because of linguistic faculty; however, Nack exhibited the same understanding as humans.
白鲸通过叫声向群体成员传达各种信息。这种交流方式与人类相似吗？我们通过使用刺激等价性框架来解决这个问题。刺激等价性包括三个阶段：如果动物被训练将 A 与 B 匹配，B 与 C 匹配，则通过匹配 BA 和 CB 来证明对称，通过匹配 AC 来证明传递性，通过匹配 CA 来证明等价性。我们测试了一只名为 Nack 的白鲸在视觉和听觉符号之间自发建立跨模态刺激等价性的能力。Nack 可以在未经训练的新物体上进行对称选择。此外，视觉/听觉跨模态传递性也自发形成。Nack 在包括一个未训练任务的六个任务中都取得了成功。我们得出结论，Nack 在视觉和听觉符号之间自发形成了跨模态刺激等价性。由于语言能力，跨模态刺激等价性被认为只存在于人类中；然而，Nack 表现出了与人类相同的理解能力。
