Speech is a fundamental means of communication that can be seen to provide two channels for transmitting information: the lexical channel of which words are said, and the non-lexical channel of how they are spoken. Both channels shape listener expectations of upcoming communication; however, directly quantifying their relative effect on expectations is challenging. Previous attempts require spoken variations of lexically-equivalent dialogue turns or conspicuous acoustic manipulations. This paper introduces a generalised paradigm to study the value of non-lexical information in dialogue across unconstrained lexical content. By quantifying the perceptual value of the non-lexical channel with both accuracy and entropy reduction, we show that non-lexical information produces a consistent effect on expectations of upcoming dialogue: even when it leads to poorer discriminative turn judgements than lexical content alone, it yields higher consensus among participants.

翻译：言语作为一种基本的沟通方式，可被视为提供两条信息传输通道：词汇通道（即所说的话语内容）与非词汇通道（即话语的说话方式）。这两条通道共同塑造了听者对后续交际的预期；然而，直接量化它们对预期的相对影响颇具挑战性。以往的研究需要词汇等价的对话轮次变体或显著的声学操控。本文提出一种通用范式，用于研究非词汇信息在不受词汇内容限制的对话中的价值。通过以准确率和熵减两种方式量化非词汇通道的感知价值，我们发现非词汇信息对后续对话的预期产生一致的影响：即使其导致的对话轮次判别准确性低于仅依赖词汇内容的情况，参与者之间的共识度反而更高。