Hearing the forest despite the trees: Perceptual learning of systematic variation in speech.

Abstract

A fundamental problem for the understanding of spoken language processing is listeners’ robust perceptual constancy in the face of enormous variability in the instantiation of linguistic form. On the one hand, listeners are sensitive to the fine-grained structure of linguistic segments that signal differences among talkers and speaking styles. On the other hand, listeners tolerate large discontinuities in this same fine structure forming robust, perceptually constant linguistic categories. Data from a perceptual learning paradigm addressing both the limits and flexibility of speech perceptual mechanisms will be presented and discussed in light of evidence for perceptual learning of accented speech. In a series of studies, listeners were exposed to accented English under learning conditions in which the opportunity to compare across instances varied. At test, generalization and long-term retention of perceptual learning were evaluated. The results suggest that adaptation to lawful variation in speech is fundamentally influenced by the character and structure of the learning experience. These findings suggest cognitive constraints on behavioral and representational plasticity in speech perception and spoken language processing.