Contextual predictability and phonetic attention

Abstract

The interaction of contextual, high-level linguistic knowledge and the listener’s attention to low-level phonetic details has been the subject of a large body of research in speech perception for several decades. In the current paper, I investigate this interaction by considering the specific phenomenon of word predictability and its role in modulating the listener’s attention to subphonemic details of the acoustic signal. In the first experiment, subjects are presented with a discrimination task in which target words are presented in either predictable or unpredictable sentential context and then repeated in isolation, being either acoustically identical or subtly different. The subjects more accurately discriminate contextually unpredictable words, suggesting more attention to the phonetic details of words in unpredictable contexts. In the second experiment, considering the predictions of exemplar theory, I test whether this perceptual bias could result in changes in production. In this experiment, in which subjects heard and repeated sentences, I find a significant effect of word predictability on how close the subjects’ productions were to the model’s, which suggests a role of predictability on phonetic accommodation. The results of these experiments contribute to our understanding of stored exemplars and suggest the influence of contextual predictability in sound change.