Effects of Native Language and Linguistic Exposure on Non-Native Listeners' Use of Prosodic Cues in Speech Segmentation

University Of Kansas Center For Research Inc, Lawrence KS

Investigators

Abstract

Speech is a continuous flow of sounds where no single device explicitly marks word boundaries. A crucial challenge for language learners is that the cues that signal word boundaries differ across languages; thus, a speaker's experience with her native language may be misleading when attempting to segment a second language into words. Specifying how adult language learners recognize words in continuous speech is very important, first because it can help resolve key theoretical debates about how language learning and language comprehension take place in adults. More precisely, it can shed light on whether (and if so, the extent to which) the adult brain is sufficiently plastic to develop sensitivity to new segmentation cues and the factors that modulate whether or not this learning is possible. This research can therefore have important implications for cognitive and linguistic sciences. Furthermore, speech segmentation is essential to successful communication among multilingual speakers. As our society is becoming increasingly multilingual, languages have become intrinsic components of K-12 and college curricula, and computational linguists and computer scientists have striven to develop technologies that could afford efficient communication among multilingual speakers. Investigating the factors that influence how adult language learners segment a second language into words can thus have important implications for the teaching of languages and for the development of communication technologies (e.g., automatic speech recognition). This research focuses on the influence of the native language and of recent linguistic exposure on adult language learners' use of prosodic cues, specifically pitch, in speech segmentation. Its primary aim is to determine how the similarities and differences between the native language and second language affect adult language learners' ability to use prosodic cues in speech segmentation. Two hypotheses are tested: (i) the Prosodic Assimilation Hypothesis: Second-language prosodic systems that are similar to, yet different from, native-language prosodic systems are assimilated and thus more difficult to learn in speech segmentation than second-language prosodic systems that are very different from native-language prosodic systems; and (ii) the Cue-Weighting Transfer Hypothesis: The functional load of segmentation cues in the native language is carried over to the second language. A secondary aim of this research is to assess the effect of recent linguistic exposure on speech segmentation. A third hypothesis is tested: (iii) Probabilistic Speech Segmentation Hypothesis: The speech processing system uses a single set of speech segmentation strategies that reflect the probabilities of cues to word boundaries across the native language and second language. To test these hypotheses, this research focuses on native French, Korean, English, and Dutch listeners with or without knowledge of French or Korean as second languages. Listeners will complete visual-world eye-tracking and artificial-language segmentation experiments.