Six-month-olds infer object size based on pitch: they map high-pitched vowels onto smaller objects and low-pitched vowels onto larger objects (Peña et al., 2011). The ‘sound symbolism bootstrapping hypothesis’ (Imai & Kita, 2014) proposes that this may support understanding of word-meaning correspondences; by drawing on iconic pairings between linguistic cues and corresponding referents (e.g., higher pitch for smaller objects), infants develop understanding of word-referent associations. Here we analyse mother-child interactions, testing whether sound-symbolic pitch-size correspondences occur in infant-directed speech. 40 dyads engaged in (semi-)naturalistic interaction around picture books containing images of toys of varying sizes. We compare mothers’ pitch when referring to small versus large toys, analysing i) actual size (bigger vs. smaller toys); ii) relative toy size congruence (i.e., congruent vs. incongruent with real-world expectation); and iii) transparency of the test paradigm as regards its focus on size contrastiveness (non-transparent, moderately transparent, highly transparent) to observe the nuances of size sound symbolism in infant-directed speech.

中文翻译：

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大小在母亲对婴儿的言语中具有听起来的象征意义


六个月大的孩子根据音高推断物体的大小：他们将高音元音映射到较小的物体上，将低音调元音映射到较大的物体上（Peña et al.， 2011）。'声音象征引导假说'（Imai & Kita， 2014）提出这可能支持对词义对应关系的理解;通过利用语言线索和相应指涉对象之间的标志性配对（例如，较小的物体的音调更高），婴儿可以理解单词-指称的联想。在这里，我们分析了母子互动，测试了婴儿定向语音中是否会出现声音-符号音高-音高大小的对应关系。40 个二人组围绕包含不同大小玩具图像的图画书进行（半）自然主义互动。我们比较了妈妈们在提到小型玩具和大型玩具时的音高，分析了 i） 实际尺寸（更大与更小的玩具）;ii） 玩具尺寸的相对一致性（即与现实世界的期望一致与不一致）;iii） 测试范式的透明度，因为它关注大小对比性（不透明、中等透明、高度透明），以观察婴儿导向的语音中大小声音象征的细微差别。