The present study investigated whether advanced late second-language (L2) learners adapt their perceptual categorization in response to categorical segmental substitutions in L2 words, and whether this differs depending on the difficulty of the targeted phonological contrast. In three experiments, German learners of English categorized acoustic continua for a contrast that also exists in their L1 (/i/-/ɪ/), and one that does not and is known to be challenging for them (/ɛ/-/æ/). Crucially, they did so after listening to sets of English words that were either all canonically produced or contained items with /ɪ/ →[i] and /æ/ →[ɛ] substitutions. Experiment 1 used the same male talker for exposure and test, Experiment 2 another male test talker with similar acoustics and Experiment 3 a female test talker. Results showed perceptual recalibration effects in the expected direction for /i/-/ɪ/ in Experiments 1 and 2, and a shift in the opposite direction for /ɛ/-/æ/ only in Experiment 1. This study extends previous findings to a non-native population and to vowel distinctions, provides novel insights on the cross-talker generalizability of perceptual recalibration effects and, importantly, highlights the need for more research investigating perceptual adaptation processes involving difficult non-native contrasts.

Anticipatory contextual nasalization, whereby an oral segment (usually a vowel) preceding a nasal consonant becomes partially or fully nasalized, has received considerable attention in research that seeks to uncover predictive factors for the temporal domain of coarticulation. Within this research, it has been claimed that the phonological status of vowel nasality in a language can determine the temporal extent of phonetic nasal coarticulation. We present a comparative study of anticipatory nasal coarticulation in American English, Northern Metropolitan French, and Standard German. These languages differ in whether nasality is contrastive (French), ostensibly phonologized but not contrastive (American English), or neither (German). We measure nasal intensity during a comparatively large temporal interval preceding a nasal or oral control consonant. In English, coarticulation has the largest temporal domain, whereas in French, anticipatory nasalization is more constrained. German differs from English, but not from French. While these results confirm some of the expected language-specific effects, they underscore that the temporal extent of anticipatory nasal coarticulation can go beyond the preceding vowel if the context does not inhibit velum lowering. For all languages, the onset of coarticulation may considerably precede the pre-nasal vowel in VN sequences, especially so for English. We propose that in English, the pre-nasal vowel has itself become a source of coarticulation, making American English pre-nasal vowel nasality uninformative about coarticulatory nasalization. Degrees of individual variation between the languages align with the phonological or phonologized role of nasalization therein. Overall, our data further add to our understanding of the non-local temporal scope of anticipatory coarticulation and its language-specific expressions.

Diphthong vowels exhibit a degree of inherent dynamic change, the extent of which can vary synchronically and diachronically, such that diphthong vowels can become monophthongs and vice versa. Modelling this type of change requires defining diphthongs in opposition to monophthongs. However, formulating an explicit definition has proven elusive in acoustics and articulation, as diphthongisation is often gradient in these domains. In this study, we consider whether diphthong vowels form a coherent phonetic category from the articulatory point of view. We present articulometry and acoustic data from six speakers of Northern Anglo-English producing a full set of phonologically long vowels. We analyse several measures of diphthongisation, all of which suggest that diphthongs are not categorically distinct from long monophthongs. We account for this observation with an Articulatory Phonology/Task Dynamic model in which diphthongs and long monophthongs have a common gestural representation, comprising two articulatory targets in each case, but they differ according to gestural constriction and location of the component gestures. We argue that a two-target representation for all long vowels is independently supported by phonological weight, as well as by the nature of historical diphthongisation and present-day dynamic vowel variation in British English.