Spoken word recognition in a second language: The importance of phonetic details

Abstract

Spoken word recognition depends on variations in fine-grained phonetics as listeners decode speech. However, many models of second language (L2) speech perception focus on units such as isolated syllables, and not on words. In two eye-tracking experiments, we investigated how fine-grained phonetic details (i.e. duration of nasalization on contrastive and coarticulatory nasalized vowels in Canadian French) influenced spoken word recognition in an L2, as compared to a group of native (L1) listeners. Results from L2 listeners (English-native speakers) indicated that fine-grained phonetics impacted the recognition of words, i.e. they were able to use nasalization duration variability in a way similar to L1-French listeners, providing evidence that lexical representations can be highly specified in an L2. Specifically, L2 listeners were able to distinguish minimal word pairs (differentiated by the presence of phonological vowel nasalization in French) and were able to use variability in a way approximating L1-French listeners. Furthermore, the robustness of the French “nasal vowel” category in L2 listeners depended on age of exposure. Early bilinguals displayed greater sensitivity to some ambiguity in the stimuli than late bilinguals, suggesting that early bilinguals had greater sensitivity to small variations in the signal and thus better knowledge of the phonetic cue associated with phonological vowel nasalization in French, similarly to L1 listeners.

Exploring individual differences in native phonetic perception and their link to nonnative phonetic perception.

“…This possibility is supported by work showing that native and nonnative listeners rely on different strategies—namely, lexical knowledge versus acoustic cues—during word segmentation (Mattys et al, 2010). It has also been found that native speakers show gradient integration of phonetic information (as measured by eye-tracking) during word recognition, whereas nonnative speakers show a categorical pattern (Desmeules-Trudel, 2018). An additional possibility is that greater sensitivity to native speech sounds does promote better nonnative perception, but that this relationship emerges later in life.…”

Individual Differences in Categorical Judgment of L2 Stops: A Link to Proficiency and Acoustic Cue-Weighting

“…For example, Mattys et al (2010) showed that in the presence of cognitive load (speech perception accompanied by a distracting visual search task), native and non-native listeners' word segmentation relied on a different source of information; non-native listeners tend to make less use of lexical knowledge and more use of acoustic cues compared to native listeners. Similarly, Desmeules-Trudel (2018) reported that French-speaking L2 learners of Canadian English (even those with early exposure to the L2) patterned differently from L1 Canadian English listeners in integrating fine-grained acoustic information (nasalization duration of nasal vowels) for spoken word recognition. L2 learners were not gradient (but rather categorical) in word recognition as acoustic information of nasalization duration varied, whereas L1 listeners responded to conflicting acoustic information in a gradient manner.…”

Prosodic Structural Effects on Non-Contrastive Coarticulatory Vowel Nasalization in L2 English by Korean Learners

“…An increasing number of studies on L2 phonetics, indeed, have suggested that learners can be sensitive to the phonetic detail in L2 and eventually learn to produce it, enriching the model architecture of SLM(-r) and PAM-L2 in terms of the role of the non-contrastive phonetic detail in L2 acquisition (see Flege, 2003, or Best & Tyler, 2007, for a review). In terms of L2 perception of non-contrastive cues, for example, evidence from psycholinguistic studies indicates that L2 listeners utilize fine-grained phonetic details (i.e., vowel nasalization duration) when perceiving L2 sounds or words (e.g., Desmeules-Trudel & Zamuner, 2021). In terms of production, a seminal study by Flege (1987) showed that both native English learners of French and native French learners of English were sensitive to the phonetic detail of VOT in each target language, producing VOTs that were different from those in their native languages but closer to those of each target language.…”