Watson Stuart K, Mine Joseph G, O'Neill Louis G, Mueller Jutta L, Russell Andrew F, Townsend Simon W
Department of Comparative Language Science, University of Zurich, Zurich, Switzerland.
Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.
iScience. 2023 May 26;26(7):106977. doi: 10.1016/j.isci.2023.106977. eCollection 2023 Jul 21.
A critical component of language is the ability to recombine sounds into larger structures. Although animals also reuse sound elements across call combinations to generate meaning, examples are generally limited to pairs of distinct elements, even when repertoires contain sufficient sounds to generate hundreds of combinations. This combinatoriality might be constrained by the perceptual-cognitive demands of disambiguating between complex sound sequences that share elements. We test this hypothesis by probing the capacity of chestnut-crowned babblers to process combinations of two versus three distinct acoustic elements. We found babblers responded quicker and for longer toward playbacks of recombined versus familiar bi-element sequences, but no evidence of differential responses toward playbacks of recombined versus familiar tri-element sequences, suggesting a cognitively prohibitive jump in processing demands. We propose that overcoming constraints in the ability to process increasingly complex combinatorial signals was necessary for the productive combinatoriality that is characteristic of language to emerge.
语言的一个关键组成部分是将声音重新组合成更大结构的能力。尽管动物也会在不同的叫声组合中重复使用声音元素来产生意义，但例子通常仅限于成对的不同元素，即使其声音库包含足够的声音来产生数百种组合。这种组合性可能受到区分共享元素的复杂声音序列时感知认知需求的限制。我们通过探究栗冠弯嘴鹛处理两个与三个不同声学元素组合的能力来检验这一假设。我们发现，与熟悉的双元素序列回放相比，弯嘴鹛对重组双元素序列回放的反应更快且持续时间更长，但没有证据表明它们对重组三元素序列回放与熟悉的三元素序列回放有不同反应，这表明处理需求在认知上有一个难以跨越的跳跃。我们提出，克服处理日益复杂的组合信号能力的限制对于语言所特有的高效组合性的出现是必要的。
