Kamath Gaurav, Yang Michelle, Reddy Siva, Sonderegger Morgan, Card Dallas
Department of Linguistics, McGill University, Montreal, QC H3A 1A7, Canada.
Mila-Quebec AI Institute, Montreal, QC H2S 3H1, Canada.
Proc Natl Acad Sci U S A. 2025 Aug 5;122(31):e2426815122. doi: 10.1073/pnas.2426815122. Epub 2025 Jul 28.
A central question in the study of language change is whether or not such change is generational. If a language changes over time generation-by-generation, the process looks as follows: New generations of speakers introduce innovations, while older speakers conserve their usage patterns, and the language changes as new generations replace older ones. At the opposite extreme, language change could be a zeitgeist phenomenon, in which changes are universally adopted by speakers simultaneously, regardless of age or generational cohort. This paper asks this question in the context of word meaning change. We analyze meaning change in over 100 words across more than 7.9 million U.S. congressional speeches, to observe whether, when a word sense rises or falls in prominence, adult speakers from different generations uniformly adopt it, or those from older generations conserve their prior usage. Using language model-based word sense induction methods, we identify different senses of each word, and then model the prevalence of each of these word senses as a function of time and speaker age. We find that most words show a small but statistically significant effect of speaker age; across almost 140 y of Congress, older speakers typically take longer than younger speakers to follow changes in word usage, but nevertheless do so within a few years. Our findings indicate that despite minor age-based differences, word meaning change among mature speakers is likely not a generational process, but rather a zeitgeist process, in which older adult speakers can readily adopt new word usage patterns.
语言变化研究中的一个核心问题是这种变化是否具有代际性。如果一种语言随着时间代代相传地发生变化，其过程如下：新一代的使用者引入创新，而年长的使用者保留他们的使用模式，随着新一代取代老一代，语言也随之改变。与之相反的极端情况是，语言变化可能是一种时代精神现象，即无论年龄或代际群体如何，使用者会同时普遍采用这些变化。本文在词义变化的背景下探讨这个问题。我们分析了超过790万份美国国会演讲中100多个单词的意义变化，以观察当一个词义的突出程度上升或下降时，不同代的成年使用者是一致采用它，还是老一辈使用者保留他们先前的用法。使用基于语言模型的词义归纳方法，我们识别出每个单词的不同词义，然后将这些词义的流行程度建模为时间和使用者年龄的函数。我们发现，大多数单词显示出使用者年龄的微小但具有统计学意义的影响；在近140年的国会历史中，年长的使用者通常比年轻的使用者需要更长时间来跟上词汇用法的变化，但最终也会在几年内做到。我们的研究结果表明，尽管存在基于年龄的微小差异，但成熟使用者之间的词义变化可能不是一个代际过程，而是一个时代精神过程，在这个过程中，年长的成年使用者可以很容易地采用新的词汇使用模式。
