Yui Suzukida

Identifying which segmental contrasts should be prioritised for speech intelligibility is a central issue in L2 pronunciation research and pedagogy. Functional load (FL) provides a principled basis, yet existing rankings are often insufficiently explicit, largely language-internal, and only partly validated against L2 speech outcomes. This study proposed an updated FL framework for English phonemic contrasts. Study 1 reconstructed Brown’s (1988) FL logic using corpus-derived lexical, frequency, phonetic, contextual, regional, and lexical-competition variables. Study 2 extended this model by incorporating Japanese learners’ perceptual difficulty based on assimilation judgments, goodness-of-fit ratings, and contrast-level discrimination. The learner model increased the priority of contrasts known to be difficult for Japanese users of English while preserving the corpus-based FL foundation. Study 3 examined semi-spontaneous speech from 40 Japanese learners and showed that high-FL substitution errors significantly predicted lower comprehensibility after syllable, word-stress, and intonation errors were controlled, whereas low-FL errors made no unique contribution.

To contribute to the ongoing discussion on the role of pitch processing in grammar learning, this study examines the extent to which pitch statistical learning (pitch statistical learning (SL); the ability to detect and internalize pitch patterns in auditory input) affects second language (L2) morphosyntax learning outcomes. In the context of 93 Japanese learners of English, piece-wise regression analyses were conducted to compare the roles of their pitch SL abilities and pitch acuity in L2 morphosyntactic knowledge. The results revealed a weak but significant positive correlation between pitch SL and morphosyntactic knowledge, whereas pitch acuity showed no significant association. Further analysis identified a threshold effect: pitch SL has a strong association with morphosyntactic knowledge for learners with lower pitch SL abilities, but not for those with higher pitch SL abilities. These findings suggest that the lack of pitch SL ability could substantially slow down L2 morphosyntactic learning.

By adopting a pre- and post-test design, the current study longitudinally examined the complex relationship between two different dimensions of phonological vocabulary knowledge (declarative vs. automatized) and their ultimate impacts on global L2 listening proficiency among 133 Japanese EFL students. The declarative group focused solely on what target words sound like and mean via meaning recognition tasks. The automatization group worked not only on such form-meaning mappings but also on prompt access to the target words in a semantically, collocationally, and grammatically appropriate manner via lexicosemantic judgment tasks. Compared to the declarative group, the automatization group showed relatively robust learning in both declarative and automatized dimensions of target words. Although neither training approach showed clear superiority, the results suggest that relative gains in automatized, rather than declarative, dimensions are associated with enhanced L2 listening proficiency. The distinction between declarative and automatized dimensions of phonological vocabulary knowledge, along with the absence of a direct link between training type and improved listening proficiency, offers valuable insights for future extension studies.

This study revisits the roles of different aspects of phonological vocabulary knowledge in second language (L2) listening. Japanese learners of English (n = 114) completed the TOEIC Listening test and three phonological vocabulary tests assessing (a) ability to recognize the meanings of aural forms (meaning recognition), (b) ability to recall the meanings of aural forms (meaning recall), and (c) ability to spontaneously judge the appropriate use of word meanings in sentential contexts (lexicosemantic judgment task [LJT]). Among the three measures, the LJT best predicted the participants’ ability to access the target words during real‐life L2 listening comprehension of monologues and conversations (measured via TOEIC). Structural equation modeling demonstrated that the LJT was distinct from both meaning recognition and recall and revealed their different associations with listening comprehension scores. In line with the skill acquisition theory, we propose that the LJT reflects automatized knowledge, whereas meaning recognition and recall represent declarative knowledge.

Misalignment between second language (L2) self-perception and actual ability is often observed among L2 learners. In order to further understand this phenomenon, the current study investigated how the roles of individual differences (IDs; especially experiential and cognitive IDs) influence the learners’ self-assessment accuracy. To this end, L2 speech samples elicited from 97 Japanese learners of English were analyzed via self-evaluation and expert evaluations. Subsequently, learners’ IDs profiles, including working memory, phonological memory, implicit learning and auditory processing, were linked to (a) the gap between self- and expert evaluation scores and (b) the type of inaccurate self-evaluation (i.e., overconfident vs. underconfident evaluations). The study illustrates the complex relationships between L2 learners’ linguistic knowledge, cognitive abilities, experiential profiles and self-perception.

In this two-part study, we conducted both cross-sectional and longitudinal investigations on the relative weights of experiential, cognitive, and sociopsychological factors in adult L2 speech learning. In the cross-sectional phase (Study 1), speech was elicited from 73 Japanese speakers of English via a picture description task, and rated for accentedness and comprehensibility. These scores were linked to scores on a range of tests designed to measure aptitude, motivation, and anxiety. The results showed that comprehensibility was exclusively linked to experiential variables (e.g., the amount of L2 use outside classrooms), while accentedness was linked to phonemic coding ability and anxiety. In the longitudinal phase (Study 2), we tracked the same participants' L2 comprehensibility and accentedness development when they received four weeks of explicit pronunciation instruction. According to the results of pre- and post-tests, participants significantly improved the comprehensibility and accentedness of their speech regardless of cognitive and sociopsychological differences.

Scholars have extensively investigated the effectiveness of high variability phonetic training (HVPT), that is, identification and discrimination of second language speech sounds produced by multiple speakers followed by trial‐by‐trial feedback. Building on the notion of incidental and multimodal learning in cognitive psychology (e.g., Lim & Holt, 2011), we developed a new, HVPT‐based videogame paradigm in which participants aimed to shoot clay targets as fast as possible while being guided to learn sound cues as a by‐product of planned learning. Focusing on the speech acquisition of 58 Japanese English‐as‐a‐foreign‐language learners, the current study set out to test the pedagogical potential and limits of the incidental HVPT approach. According to the results of statistical analyses, the effectiveness of incidental HVPT can be more clearly observed if it focuses on more learnable targets (e.g., acquisition of English [æ]–[ʌ] rather than [r]–[l] contrasts) with gains being more generalizable from trained to new speakers’ voices and from perception to production dimensions.

Extending the paradigm in L1 acquisition, scholars have begun to investigate whether participants’ domain-general ability to represent, encode, and integrate spectral and temporal dimensions of sounds (i.e., auditory processing) could be a potential determinant of the outcomes of post-pubertal L2 speech learning. The current study set out to test the hypothesis that auditory processing makes auniquecontribution to L2 speech acquisition, for 70 Japanese classroom learners of English with different levels of L2 proficiency when biographical backgrounds (length of instruction and immersion)andmemory abilities (working, declarative, and procedural memory) are controlled for. Auditory processing loaded onto modality-general capacities to represent and incorporate anchor stimuli (relative to target stimuli) into long-term memory in an implicit fashion, but dissociated from explicit abilities to remember, associate, and elaborate sensory information. Auditory processing explained a small-to-medium amount of variance in L2 speech learning, even after the other potentially confounding variables were statistically factored out.