Whereas a growing amount of attention has been directed to the role of perceptual-cognitive aptitude in successful second language (L2) lexicogrammar learning, scholars have begun to investigate the same topic in the context of L2 pronunciation learning. To date, there is ongoing discussion on the mechanism underlying L2 speech learning in…

Growing evidence suggests that auditory processing ability may be a crucial determinant of language learning, including adult second language (L2) speech learning. The current study tested 47 Chinese English-as-a-Foreign-Language students to examine the extent to which two types of auditory processing, i.e., perceptual acuity and audio-motor…

In this study, we propose a hypothesis that domain-general auditory processing, a perceptual anchor of L1 acquisition, can serve as the foundation of successful post-pubertal L2 learning. This hypothesis was tested with 139 post-pubertal L2 immersion learners by linking individual differences in auditory discrimination across multiple acoustic…

The current study examines how second language (L2) users differentially assess the comprehensibility (i.e., ease of understanding) of foreign-accented speech according to a range of background variables, including first language (L1) profiles, L2 proficiency, age, experience, familiarity, and metacognition. A total of 110 L2 listeners first…

The current study examined the degree to which collocation use (i.e., meaningful co-occurrences of multiple words) is related to first language (L1) raters' intuitive judgments of second language (L2) speech. Speech samples from a picture description task performed by 85 Japanese learners of English with varied L2 proficiency profiles were…

To date, a growing number of studies have shown that domain-general auditory processing, which prior work has linked to L1 acquisition, could explain various dimensions of naturalistic L2 speech proficiency. The current study examined the generalizability of this topic to L2 speech learning in classroom settings. The spontaneous speech samples of…

The purpose of this case study is twofold: it (1) explores multilingual raters' judgements regarding the accentedness and comprehensibility of second language speech and (2) examines how the raters' language backgrounds influence their judgements. In this study, six multilingual Singaporean raters judged the accentedness and comprehensibility of…

Building up on Munro and Derwing, the current study set out to re-examine and generalize the Functional Load (FL) principle (Brown, 1988) as a tool to identify a set of relatively crucial segmental features for successful understanding in L2 communication. In Experiment 1, 40 Japanese learners of English in English-as-Foreign-Language settings…

The current study examined lexical aspects of second language (L2) speech attainment in the foreign language (FL) classroom setting (i.e., several hours of target language input per week). A total of 72 second-year university students with 7 years of FL study and no experience abroad participated in the study. Their spontaneous speech was analyzed…

There is emerging evidence that collocation use plays a primary role in determining various dimensions of L2 oral proficiency assessment and development. The current study presents the results of three experiments which examined the relationship between the degree of association in collocation use (operationalized as t scores and mutual…

This study examined how longitudinal interaction impacts the development of second language (L2) oral proficiency in relation to learners' different experience and proficiency levels. Japanese learners of English as a foreign language (EFL) participated in weekly conversation exchanges with native speakers (NSs) in the USA via videoconferencing…

The current project longitudinally investigated the extent to which first-year Japanese university students developed their second language (L2) oral ability in relation to increased input in foreign language classrooms. Their spontaneous speech was elicited at the beginning, middle and end of one academic year, and then judged by linguistically…

The current project examined whether and to what degree age of acquisition (AOA), defined as the first intensive exposure to a second language (L2) environment, can be predictive of the end state of postpubertal L2 oral proficiency attainment. Data were collected from 88 experienced Japanese learners of English and two groups of 20 baseline…

The current study investigated the extent to which L2 learners' productive vocabulary knowledge could predict multiple dimensions of spontaneous speech production. A total of 39 English as a foreign language (EFL) participants with varying L2 proficiency levels first completed a productive vocabulary knowledge task (Lex30). Their spontaneous…

The current study examined the extent to which native speakers of North American and Singapore English differentially perceive the comprehensibility (ease of understanding) of second language (L2) speech. Spontaneous speech samples elicited from 50 Japanese learners of English with various proficiency levels were first rated by 10 Canadian and 10…