Elicited Imitation Tests (EITs) are commonly used in second language acquisition (SLA)/bilingualism research contexts to assess the general oral proficiency of study participants. While previous studies have provided valuable EIT construct-related validity evidence, some key gaps remain. This study uses an integrative data analysis to further probe the validity of the Korean EIT score interpretations by examining the performances of 318 Korean learners (198 second language, 79 foreign language, and 41 heritage) on the Korean EIT scored by five different raters. Expanding on previous EIT validation efforts, this study (a) examined both inter-rater reliability and differences in rater severity, (b) explored measurement bias across subpopulations of language learners, (c) identified relevant linguistic features which relate to item difficulty, and (d) provided a norm-referenced interpretation for Korean EIT scores. Overall, findings suggest that the Korean EIT can be used in diverse SLA/bilingualism research contexts, as it measures ability similarly across subgroups and raters.

One of the basic goals of second language (L2) speech research is to understand the perception-production link, or the relationship between L2 speech perception and L2 speech production. Although many studies have examined the link, they have done so with strikingly different conceptual foci and methods. Even studies that appear to use similar perception and production tasks often present nontrivial differences in task characteristics and implementation. This conceptual and methodological variation makes meaningful synthesis of perception-production findings difficult, and it also complicates the process of developing new perception-production models that specifically address how the link changes throughout L2 learning. In this study, we scrutinize theoretical and methodological issues in perception-production research and offer recommendations for advancing theory and practice in this domain. We focus on L2 sound learning because most work in the area has focused on segmental contrasts.

One feature of Spanish that presents some difficulties to second language (L2) learners whose first language (L1) is English concerns lexical stress. This study explores one aspect of the obstacle these learners face, weak phonological processing routines concerning stress inherited from their native language. Participants were L1 English L2 learners of Spanish. The experiment was a sequence-recall task with auditory stimuli minimally contrasting in stress (target) or segmental composition (baseline). The results suggest that learners are more likely to accurately recall sequences with stimuli contrasting in segmental composition than stress, suggesting reduced phonological processing of stress relative to a processing baseline. Furthermore, an increase in proficiency—assessed by means of grammatical and lexical tests—was found to be modestly associated with an increase in the accuracy of processing stress. We conclude that the processing routines of native English speakers lead to an acquisitional obstacle when learning Spanish as a L2.

This study brings together two previously largely independent fields of multilingual language acquisition: heritage language and third language (L3) acquisition. We investigate the production of fortis and lenis stops in semi-naturalistic speech in the three languages of 20 heritage speakers (HSs) of Italian with German as a majority language and English as L3. The study aims to identify the extent to which the HSs produce distinct values across all three languages, or whether crosslinguistic influence (CLI) occurs. To this end, we compare the HSs’ voice onset time (VOT) values with those of L2 English speakers from Italy and Germany. The language triad exhibits overlapping and distinct VOT realizations, making VOT a potentially vulnerable category. Results indicate CLI from German into Italian, although a systemic difference is maintained. When speaking English, the HSs show an advantage over the Italian L2 control group, with less prevoicing and longer fortis stops, indicating a specific bilingual advantage.

This article discusses the conceptualization, measurement, and validity of a recently emerged construct in the field of second language acquisition (SLA)—implicit language aptitude (alternatively “implicit aptitude”). Implicit aptitude is a set of cognitive abilities that enable learners to make unconscious computations of the distributional and transitional probabilities of linguistic input. Implicit aptitude is key to an accurate understanding of the cognitive foundation of language learning and contributes significantly to the advancement of SLA theory and pedagogy. The article starts by clarifying the concept and components of implicit aptitude, elaborating its role in SLA theories, identifying its attributes, and discussing its measurement. It then synthesizes the empirical evidence on its divergent, convergent, and predictive validity, which refers to whether it is distinct or separable from explicit aptitude, whether measures of implicit aptitude are correlated, and whether it is predictive of learning outcomes, respectively. Next, the article provides an overview of the seven empirical studies included in this special issue that examined implicit aptitude from various perspectives. The article concludes by identifying future directions.

Listener-based ratings have become a prominent means of defining second language (L2) users’ global speaking ability. In most cases, local listeners are recruited to evaluate speech samples in person. However, in many teaching and research contexts, recruiting local listeners may not be possible or advisable. The goal of this study was to hone a reliable method of recruiting listeners to evaluate L2 speech samples online through Amazon Mechanical Turk (AMT) using a blocked rating design. Three groups of listeners were recruited: local laboratory raters and two AMT groups, one inclusive of the dialects to which L2 speakers had been exposed and another inclusive of a variety of dialects. Reliability was assessed using intraclass correlation coefficients, Rasch models, and mixed-effects models. Results indicate that online ratings can be highly reliable as long as appropriate quality control measures are adopted. The method and results can guide future work with online samples.

In two visual priming experiments, we investigated the relation of form-identical word forms with different grammatical functions in L1 and L2 German. Four different grammatical types (inflected verbs, infinitives, deverbal conversion forms, and countable nouns) were used as primes and their influence on the processing of form-identical inflected verbs as targets was compared. Results revealed full priming of inflected verbs, but only partial priming for conversion forms and infinitives. No priming was observed for semantically related countable nouns suggesting that they have a separate lexical entry. The findings bring first psycholinguistic evidence for typological claims that deverbal conversion nouns and infinitives fall into the category of nonfinites. They also support accounts assuming representations with a basic lexical entry and word-category specific subentries. The same priming pattern was observed in L1 and L2 suggesting that representation and processing of the studied complex forms is not fundamentally different in the two populations.

Eighty Japanese learners of English as a foreign language encountered 40 target words in one of four experimental conditions (three encounters, six encounters, three encounters with talker variability, and six encounters with talker variability). A picture-naming test was conducted three times (pretest, immediate posttest, and delayed posttest) and elicited speech samples were scored in terms of form-meaning connection (spoken form recall) and word stress accuracy (stress placement accuracy and vowel duration ratio). Results suggested that frequency of exposure consistently promoted the recall of spoken forms, whereas talker variability was more closely related to the enhancement of word stress accuracy. These findings shed light on how input quantity (frequency) and quality (variability) affect different stages of lexical development and provide implications for vocabulary teaching.

Learners of a nonnull subject language (e.g., English) whose first language (L1) is a null subject language (e.g., Spanish) can show some optionality in the interpretation of overt subject pronouns in the second language (L2). By exposing L2 learners to nativelike interpretations of pronouns in discourse, we aim at understanding how exposure can promote implicit learning of pronoun comprehension biases in a L2. A sentence comprehension task was used with intermediate-proficiency English L2 speakers (L1 Spanish) that included a pretest, an exposure phase using the priming technique, an immediate posttest, and a delayed posttest administered 6–10 days later. English learners showed a significant increase in nativelike pronoun interpretations both in the immediate posttest and in the delayed posttest, in comparison to the pretest. The results show that exposure through priming can be effective in changing L2 participants’ interpretations and that effects of exposure are persistent and may aid in the successful acquisition of pronoun resolution biases.

This study addresses the role of domain-general mechanisms in second-language learning and knowledge using an individual differences approach. We examine the predictive validity of implicit-statistical learning aptitude for implicit second-language knowledge. Participants (n = 131) completed a battery of four aptitude measures and nine grammar tests. Structural equation modeling revealed that only the alternating serial reaction time task (a measure of implicit-statistical learning aptitude) significantly predicted learners’ performance on timed, accuracy-based language tests, but not their performance on reaction-time measures. These results inform ongoing debates about the nature of implicit knowledge in SLA: they lend support to the validity of timed, accuracy-based language tests as measures of implicit knowledge. Auditory and visual statistical learning were correlated with medium strength, while the remaining implicit-statistical learning aptitude measures were not correlated, highlighting the multicomponential nature of implicit-statistical learning aptitude and the corresponding need for a multitest approach to assess its different facets.

The acquisition of a second language (L2) may be challenging in adulthood, as the phonological system of the native language (L1) can sometimes limit the perception of phonological contrasts in L2. The present study aimed to (a) examine the influence of an L1 (Hebrew) that lacks a phonemic contrast for vowel length on the ability to discriminate between short and long vowels in L2 (Arabic); and (b) assess the effect of a short training on the participants’ discrimination performance. A total of 60 participants, 20 native Arabic speakers and 40 native Hebrew speakers, were tested using the ABX procedure in two sessions that were 10 days apart. A single training session was provided for half of the Hebrew speakers (n = 20) approximately 2–3 days after the first (pretraining) testing session. The results indicated that the trained Hebrew participants’ discrimination levels (measured by accuracy and reaction times) were above chance level but were nevertheless lower in comparison to the Arabic speakers. However, a short training session was sufficient to yield a nativelike performance that generalized to untrained nonwords. These findings support the theoretical models that predict a reserved ability to acquire new phonetic/phonological cues in L2 and have important practical implications for the process of learning a new phonological system in adulthood.

Learners must develop the ability to perceive linguistic and social meaning in their second language (L2) to interact effectively, but relatively little is known about how learners link social meaning to a single phonetic variable. Using a matched-guise test targeting coda /s/ (realized as [s] or debuccalized [h]), we explore whether L2 Spanish learners identify native speakers’ social characteristics based on phonetic variants. Our results indicate that advanced learners were more sensitive to sociophonetic information; advanced listeners who had completed a phonetics course were significantly more likely to categorize /s/ reducers as Caribbean and those who had studied abroad in aspirating regions recognized a relationship between coda /s/ and status. To account for the complex interplay among proficiency, explicit instruction, and dialectal exposure in the development of L2 sociophonetic perception, we suggest the union of the L2 Linguistic Perception Model with exemplar models of phonological representation and indexical meaning.

There has recently been a surge of interest in improving the replicability of second language (L2) research. However, less attention is paid to replicability in the context of L2 meta-analyses. I argue that conducting interrater reliability (IRR) analyses is a key step toward improving the replicability of L2 meta-analyses. To that end, I first discuss the foundation of IRR in the context of meta-analytic research. Second, I introduce two IRR measures, S index and Specific Agreement, which aid in improving the replicability of meta-analytic research. Third, I offer a flexible R program, meta_rate, to facilitate the conduct of IRR analyses for L2 meta-analyses. Fourth, I apply the R program to an actual meta-analytic L2 coding sheet to demonstrate the practical use of the IRR methods discussed. Finally, I provide interpretive guidelines to assist both L2 meta-analysts and journals with the transparent reporting of the IRR findings.

Comprehensibility, or ease of understanding, has emerged as an important construct in second language (L2) speech research. Many studies have examined the linguistic features that underlie this construct, but there has been limited work on behavioral and affective predictors. The goal of this study was therefore to examine the extent to which anxiety and collaborativeness predict interlocutors’ perception of one another’s comprehensibility. Twenty dyads of L2 English speakers completed three interactive tasks. Throughout their 17-minute interaction, they were periodically asked to evaluate their own and each other’s anxiety and collaborativeness and to rate their partner’s comprehensibility using 100-point scales. Mixed-effects models showed that partner anxiety and collaborativeness predicted comprehensibility, but the relative importance of each predictor depended on the nature of the task. Self-collaborativeness was also related to comprehensibility. These findings suggest that comprehensibility is sensitive to a range of linguistic, behavioral, and affective influences.

Precise auditory perception at a subcortical level (neural representation and encoding of sound) has been suggested as a form of implicit L2 aptitude in naturalistic settings. Emerging evidence suggests that such implicit aptitude explains some variance in L2 speech perception and production among adult learners with different first language backgrounds and immersion experience. By examining 46 Chinese learners of English, the current study longitudinally investigated the extent to which explicit and implicit auditory processing ability could predict L2 segmental and prosody acquisition over a 5-month early immersion. According to the results, participants’ L2 gains were associated with more explicit and integrative auditory processing ability (remembering and reproducing music sequences), while the role of implicit, preconscious perception appeared to be negligible at the initial stage of postpubertal L2 speech learning.

Spanish monolingual speakers often produce recipient (Pedro le da un lápiz a María) and nonrecipient constructions (Antonio le lava la camiseta a Carmen) doubled by a dative clitic. Second language speakers and heritage speakers usually avoid clitics. This study examined whether structural priming could effectively increase the production of clitics in monolingual speakers (N = 23), L2 speakers (N = 28), and heritage speakers (N = 24). Participants completed a baseline study that measured the use of clitics in a picture description task, followed by a priming treatment, an immediate posttest, and a posttest a week later. Results showed that priming increased clitic production for all groups, and that the increase was still significant a week later in L2 speakers and heritage speakers. These findings support the view that structural priming may implicate implicit language learning and considers its pedagogical implications.

Speakers show cross-linguistic differences in expressing placement events involving support (cup on table) and containment (apple in bowl) in first language (L1) contexts. They rely on either more-general (e.g., Spanish for support, Polish for containment) or more-specific (e.g., German, Polish for support; Spanish, German for containment) descriptions. Relatively less is known about the expression of placement events in second language (L2) production contexts. In this study, we examined object-placement event descriptions produced by two groups of L1 Polish speakers—with either German or Spanish as their L2—in comparison to monolingual speakers of German, Spanish, and Polish, using an animated event description task. Bilingual speakers showed greater effect of L1 patterns in moving from a more-general to a more-specific system and L2 patterns in moving from a more-specific to a more-general or between two more-specific systems, suggesting that the specificity of event expression in L1 influences patterns of placement expression in L2.

A subtest of the LLAMA test battery (LLAMA_D) has been proposed as a potential test of implicit learning aptitude. To improve its construct validity, in the present study, the original LLAMA_D (a) instructions for incidental learning were modified, and (b) confidence ratings of test responses and (c) reaction time (RT) measurements were added. This revised LLAMA_D was administered along with the other LLAMA subtests (LLAMA-B, -E, and -F). Unconscious knowledge that may (not) result from the exposure was assessed through the relationship between the accuracy/RT and confidence ratings. The results suggest that LLAMA_D accuracy largely reflects conscious retrieval of previously heard sound sequences. However, an index derived from the LLAMA_D RT measure (coefficient of variance) was associated with an aspect of oral fluency, which is presumably dependent on proceduralization. Several recommendations are proposed to redesign and extend LLAMA_D as a potential aptitude test for proceduralization.

This study examines the second language (L2) development of variable /s/-weakening in the spontaneous speech of L2 learners of Spanish who studied abroad in either Dominican Republic, where /s/-weakening is widespread, or central Spain, where /s/-weakening is much less common. Learners’ realizations of /s/ were coded impressionistically and acoustically by measuring voicing, center of gravity, and duration. The results show that regardless of the study abroad location, students did not change the amount of sibilance they produced over time. However, they became more nativelike with respect to /s/-voicing and duration. Additionally, whereas some linguistic factors were found to significantly constrain /s/-weakening across groups, learners did not gain sensitivity to all factors that constrain native-speaker /s/-weakening. Findings suggest that exposure to /s/-weakening during a semester abroad is insufficient for learners to adopt this sociolinguistic variable and other social and cognitive factors likely mitigate its integration into the L2 learners’ phonological systems.

To probe the limits of attention raising through form-focused instruction, second-language research must adapt to the needs of a technologically driven learning environment. In this study, we used a randomized control design to investigate the effect of captioned media on the learning of vocabulary and grammar in L2 Spanish (n = 369 learners). Through four data-collection sessions, participants were presented with a grammar-lesson video and a multimodal video with one of three captioning formats: textually enhanced target vocabulary, textually enhanced target grammar, or no captioning. Results show strong immediate effects of captioning on target vocabulary, with additional effects of captioning on some, but not all, target-grammar structures. The findings demonstrate that (a) the learning of some grammatical structures is more conducive to captioning than others, and (b) there is space for future investigation into the factors that may influence the effectiveness of multimodal interventions, such as prior knowledge or frequency of use.