Non-native speech perception in adverse conditions: A review

Abstract

If listening in adverse conditions is hard, then listening in a foreign language is doubly so: non-native listeners have to cope with both imperfect signals and imperfect knowledge. Comparison of native and non-native listener performance in speech-in-noise tasks helps to clarify the role of prior linguistic experience in speech perception, and, more directly, contributes to an understanding of the problems faced by language learners in everyday listening situations. This article reviews experimental studies on nonnative listening in adverse conditions, organised around three principal contributory factors: the task facing listeners, the effect of adverse conditions on speech, and the differences among listener populations. Based on a comprehensive tabulation of key studies, we identify robust findings, research trends and gaps in current knowledge. 3 IntroductionFor many of us, the first non-native language experience outside the classroom is a shock. Not only are the answers to the carefully-practised stock phrases not those that appeared in the textbook, but the raw acoustic material reaching our ears lacks the clarity of the speakers in the quiet language laboratory. Thus unprepared, we enter the real world of the non-native listener, characterised by the dual challenges of imperfect signal and imperfect knowledge. And the problem persists even as we gain experience, exposure and confidence in the non-native language. Use of the telephone seems harder than it should be.Conversations in restaurants and bars are difficult to follow and join. The television never seems quite loud enough. We continue to prefer hearing non-native speakers of English at international conferences rather than highly-fluent natives. We finally take solace in the fact that even "true" bilingual listeners never quite reach the ability of monolinguals in the presence of noise (Mayo et al., 1997;Rogers et al., 2006).Knowing about the extent of problems faced by non-native listeners in adverse conditions is important in developing theories of general speech perception. Comparing adult, normal-hearing populations who differ only in their native-language experience has the potential to provide insights into the role of linguistic factors in speech decoding. Since all listeners routinely handle acoustically-complex scenarios containing competing sound sources, reverberant energy and other forms of distortion, the use of native and non-native populations allows us to explore the extent to which linguistic knowledge is used in tasks such as sound source separation and identification. To give an example, consider the processes used by listeners to handle variability in formant frequencies due to factors such as differences in vocal tract sizes. Can vocal tract length normalisation be performed purely on the basis of the speech signal itself, or does it depend on the identification of units such as vowels in the speech stream, thereby engaging higher level representations which differentiate between native and non-native listeners? More ...

Resolving ambiguity in familiar and unfamiliar casual speech

“…The same pattern appears with Dutch listeners' processing both of [ae] versus [e] (vowels that divide a single Dutch category) and of word-final voicing distinctions (which are neutralized in Dutch); in both cases Dutch listeners perform quite well in a low-level choice task (Broersma, 2005), but fail to distinguish lexical minimal pairs such as cattle-kettle or roberope in cross-modal priming (Broersma & Cutler, 2008, 2011 or in eyetracking (Escudero, Hayes-Harb, & Mitterer, 2008;Weber & Cutler, 2004). In fact one of the most wellknown L2 effects, the disproportionate difficulty of listening to an L2 in a noisy environment, shows the same pattern; a review of four decades of literature on this topic (Lecumberri, Cooke, & Cutler, 2010) motivated the conclusion that noise impinges upon the initial uptake of speech by L1 and L2 listeners to an equivalent degree, but L1 listeners recover better from its effects. We see here a similar pattern in the processing of casual speech phenomena.…”

La interpretación en las instituciones europeas: más rápido, más alto, más fuerte

“…While the scholarly literature still seems to be divided over the definition of what constitutes a bilingual speaker (see Grosjean 2016), the differentiation between second languages (L2) and foreign languages (FL) seems helpful for the discussion at hand. Although both can refer to languages learned after L1 is fully established, a language learned and spoken in an environment in which it is widely used (e.g., in the case of immigrants) is referred to as L2, while a language learned exclusively in an educational environment (e.g., in the case of languages learned at school) or through the media, is referred to as FL (García Lecumberri et al 2010). Consequently, while for L2 speakers speech perception is mainly conditioned by the quantity of signal, for FL speakers it is conditioned by both its quantity and quality.…”

Proficiency, Use of Context and Non-Native Speech Perception in Noise Performance

“…Second-language learners were chosen as the target population for their documented difficulty with speech perception in noise (Garcia Lecumberri et al, 2010). In general, studies comparing native and second-language learners suggested that normal hearing and native-like phonological awareness are fundamental for good speech perception in noise (Garcia Lecumberri et al, 2010;Mattys et al, 2012).…”

“…In general, studies comparing native and second-language learners suggested that normal hearing and native-like phonological awareness are fundamental for good speech perception in noise (Garcia Lecumberri et al, 2010;Mattys et al, 2012). In other words, perceptual problem that second-language learners experience in noise can be considered primarily due to acoustic-phonetic interference from their native language worsened by masking from noise, which in turn have cumulative detrimental impact on higher-level processes, such as syntax, semantics, and pragmatics.…”

“…In other words, perceptual problem that second-language learners experience in noise can be considered primarily due to acoustic-phonetic interference from their native language worsened by masking from noise, which in turn have cumulative detrimental impact on higher-level processes, such as syntax, semantics, and pragmatics. (Bradlow & Alexander, 2007;Cutler et al, 2004;Garcia Lecumberri et al, 2010;Mayo et al, 1997;Rogers et al, 2006). Bradlow & Alexander (2007) showed that second-language learners can benefit from contextual information only when a sentence is spoken in a clear-speech style, underscoring the importance of accurate bottom-up processing for second-language learners.…”