The effect of native vowel processing ability and frequency discrimination acuity on the phonetic training of English vowels for native speakers of Greek

Abstract

The perception and production of nonnative phones in second language (L2) learners can be improved via auditory training, but L2 learning is often characterized by large differences in performance across individuals. This study examined whether success in learning L2 vowels, via five sessions of high-variability phonetic training, related to the learners' native (L1) vowel processing ability or their frequency discrimination acuity. A group of native speakers of Greek received training, while another completed the pre-/post-tests but without training. Pre-/post-tests assessed different aspects of their L2 and L1 vowel processing and frequency acuity. L2 and L1 vowel processing were assessed via: (a) Natural English (L2) vowel identification in quiet and in multi-talker babble, and natural Greek (L1) vowel identification in babble; (b) the categorization of synthetic English and Greek vowel continua; and (c) discrimination of the same continua. Frequency discrimination acuity was assessed for a nonspeech continuum. Frequency discrimination acuity was related to measures of both L1 and L2 vowel processing, a finding that favors an auditory processing over a speech-specific explanation for individual variability in L2 vowel learning. The most efficient frequency discriminators at pre-test were also the most accurate both in English vowel perception and production after training.

More Is Less: Pitch Discrimination and Language Delays in Children with Optimal Outcomes from Autism

“…It is possible that earlier in development, auditory discrimination abilities play a unique role. For example, enhanced auditory discrimination skills seem to facilitate vowel learning for adults acquiring a second language; adults have presumably already developed a robust understanding of the role of pitch in language (Lengeris & Hazan, ). We propose that exceptionally strong pitch discrimination skills may be harmful, rather than helpful, for language acquisition during the first 2 years of life.…”

Predicting native English-like performance by native Japanese speakers

“…Other investigations into cross-linguistic speech perception have found that listeners’ L1 backgrounds influence identification and discrimination patterns (e.g., Ingram & Park, 1998), suggesting that patterns of assimilation to existing L1 categories determine performance (Flege, 2003). Iverson and Evans (2007; Lengeris & Hazan, 2010) have recently suggested that training doesn’t alter listeners’ phonetic categories but instead improves efficiency of categorization within the bounds of the existing L1 and L2 categories, highlighting the inability to change cue weightings over training as an indicator of unchanging category structure. If that is the case, it may be that something similar happens with immersion, where listeners do not fundamentally alter their category structure but instead become better at using their L1 and L2 categories to identify native and non-native speech sounds.…”

Successful second language learning is tied to robust domain-general auditory processing and stable neural representation of sound

“…The hypothesis that auditory processing may be a bottleneck for second language learning is supported by short-term training studies which have assessed auditory perception prior to asking participants to briefly learn a speech sound contrast from an unfamiliar language. These studies have found that rapid speech sound learning is linked to behavioural measures of auditory processing such as spectral (Wong & Perrachione, 2007;Lengeris & Hazan, 2010) and temporal (Kempe, Thoresen, Kirk, Schaeffler, & Brooks, 2012;Kempe, Bublitz, & Brooks, 2015) discrimination acuity, as well as greater white matter density and volume in left Heschl's gyrus (Golestani, Molko, Dehaene, LeBihan, & Pallier, 2007; and the robustness of neural encoding of speech (Chandrasekaran, Kraus, & Wong, 2011). Recently, we have shown that the robustness of neural encoding of speech is linked to English speech perception ability in native Japanese speakers (Omote, Jasmin, & Tierney, 2017) and to English speech production ability in native Mandarin Chinese speakers (Saito, Sun, & Tierney, 2018) living in the UK, suggesting that individual differences in auditory encoding may relate to L2 learning outside of the laboratory as well.…”