Seyfarth Scott
Department of Linguistics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0108, United States.
Cognition. 2014 Oct;133(1):140-55. doi: 10.1016/j.cognition.2014.06.013. Epub 2014 Jul 12.
Language-users reduce words in predictable contexts. Previous research indicates that reduction may be stored in lexical representation if a word is often reduced. Because representation influences production regardless of context, production should be biased by how often each word has been reduced in the speaker's prior experience. This study investigates whether speakers have a context-independent bias to reduce low-informativity words, which are usually predictable and therefore usually reduced. Content word durations were extracted from the Buckeye and Switchboard speech corpora, and analyzed for probabilistic reduction effects using a language model based on spontaneous speech in the Fisher corpus. The analysis supported the hypothesis: low-informativity words have shorter durations, even when the effects of local contextual predictability, frequency, speech rate, and several other variables are controlled for. Additional models that compared word types against only other words of the same segmental length further supported this conclusion. Words that usually appear in predictable contexts are reduced in all contexts, even those in which they are unpredictable. The result supports representational models in which reduction is stored, and where sufficiently frequent reduction biases later production. The finding provides new evidence that probabilistic reduction interacts with lexical representation.
语言使用者在可预测的语境中会简化词汇。先前的研究表明，如果一个单词经常被简化，那么这种简化形式可能会存储在词汇表征中。由于表征会影响语言产出，而与语境无关，因此语言产出应该会受到每个单词在说话者先前经验中被简化频率的影响。本研究调查说话者是否存在一种与语境无关的倾向，即简化信息性低的单词，这类单词通常是可预测的，因此通常会被简化。从Buckeye和Switchboard语音语料库中提取实词时长，并使用基于Fisher语料库中自发语音的语言模型分析概率性简化效应。分析结果支持了这一假设：即使在控制了局部语境可预测性、频率、语速以及其他几个变量的影响后，信息性低的单词时长仍较短。通过将单词类型仅与相同音段长度的其他单词进行比较的额外模型进一步支持了这一结论。通常出现在可预测语境中的单词在所有语境中都会被简化，即使是在不可预测的语境中。这一结果支持了这样的表征模型，即简化形式被存储，且足够频繁的简化会影响后续的语言产出。这一发现为概率性简化与词汇表征相互作用提供了新证据。
