The present electroencephalographical multi-speaker MMN oddball experiment was designed to study the phonological processing of German native and non-native speech sounds. Precisely, we focused on the perception of German /ɪ-iː/, /ɛ-ɛː/, /a-aː/ and the fricatives [ʃ] and [ç] in German natives (GG) and French learners of German (FG). As expected, our results showed that GG were able to discriminate all the critical vowel contrasts. In contrast, FG, despite their high L2 proficiency level, were only marginally sensitive to vowel length variations. Finally, neither GG nor FG discriminated the opposition between [ʃ] and [ç], as revealed by the absence of MMN response. This latter finding was interpreted in terms of low perceptual salience. Taken together, the present findings lend partial support to the Perceptual Assimilation Model for late bilinguals (PAM-L2) for speech perception of non-native phonological contrasts.

In the current study, we explore the factors underlying the well-known difficulty in acoustic classification of front nonsibilant fricatives (Maniwa, Jongman & Wade 2009, McMurray & Jongman 2011) by applying a novel classification method to the production of Greek speakers. The Greek fricative inventory [f v θ ð s z ç ʝ x ɣ] includes voiced and voiceless segments from five distinct places of articulation. Our corpus contains all of the Greek fricatives produced by 29 monolingual speakers, but our focus is on the distinction between the front nonsibilant fricatives [f v θ ð]. For comparison, we also discuss the other places of articulation where relevant. We apply a relatively novel classification method based on cepstral coefficients, previously successful in categorizing English obstruent bursts (Bunnell, Polikoff & McNicholas 2004), English vowels (Ferragne & Pellegrino 2010), Romanian fricatives (Spinu & Lilley 2016), and Russian fricatives (Spinu, Kochetov & Lilley 2018). For this study, fricative boundaries were automatically aligned using Hidden Markov Models (HMMs) and then manually checked. Six Bark-frequency cepstral coefficients (c0–c5) were extracted from 20-millisecond Hann windows. HMMs were used to divide the fricatives and adjacent vowels into three regions of internally minimized variance. A multinomial logistic regression analysis then used the mean cepstral coefficients from each region as predictors for classification by consonant identity. Our method yields highly successful classification rates, exceeding the performance of previous methods. We discuss these results in light of the differences of the phonemic distributions of fricatives between English and Greek.

This study aims at testing whether there are regional differences in the perception of the labiodental fricative contrast in Dutch. Previous production studies have shown that the devoicing of initial labiodental fricatives is a change in progress in the Dutch language area. We present the results of a speeded identification task in which fricative stimuli were systematically varied for two phonetic cues, voicing and duration. Listeners (n=100) were regionally stratified, and the regions (k=5) reflect different stages of this sound change in progress. Voicing turned out to be the strongest categorization cue in all regions; duration only played a minor role. Regional differences showed up in the perception of the consonantal contrast that matched regional differences in production reported in previous studies. The addition of random slopes in the mixed model regression showed the importance of within-regional variation.