How can we leverage digital technologies to enhance language learning and bilingual representation? In this digital era, our theories and practices for the learning and teaching of second languages (L2) have lagged behind the pace of scientific advances and technological innovations. Here we outline the approach of digital language learning (DLL) for L2 acquisition and representation, and provide a theoretical synthesis and analytical framework regarding DLL's current and future promises. Theoretically, DLL provides a forum for understanding differences between child language and adult L2 learning, and the effects of learning context and learner characteristics. Practically, findings from learner behaviors, cognitive and affective processing, and brain correlates can inform DLL-based language pedagogies. Because of its highly interdisciplinary nature, DLL can serve as an approach to integrate cognitive, social, affective, and neural dimensions of L2 learning with new and emerging technologies including VR, AI, and big data analytics.

Substantial evidence indicates that first language (L1) comprehension involves embodied visual simulations. The present study tested the assumption that a formally learned second language (L2), which is less related to real-life experiences, is processed in a less embodied manner relative to a naturally acquired L1. To this end, bilingual participants completed the same task in their L1 and L2. In the task, they read sentences and decided immediately after each sentence whether a pictured object had been mentioned in the preceding sentence. Responses were significantly faster when the shape of the object in the picture matched rather than mismatched the sentence-implied shape, but only in the L1, and only when the L1 block was performed before the L2 block. These findings suggest that embodied visual simulations are reduced in a formally learned L2 and may be subjected to cross-language influences.

In two experiments, we examine how proficient second language speakers integrate verb bias and plausibility information during online sentence comprehension. Spanish–English speakers and native English speakers read sentences in English in which a post-verbal noun phrase (NP) could be interpreted as a direct object or a sentential subject. To examine the role of verb bias, the post-verbal NP was preceded by a verb that is preferentially followed by a direct object (DO-bias verbs) or a sentential complement (SC-bias verbs). To assess the role of plausibility, the semantic fit between the verb and the post-verbal NP was either congruent or incongruent with the direct object interpretation. The results show that both second language speakers and native speakers used verb bias information to assign a grammatical role to the post-verbal ambiguous NP with small differences. Syntactic revision of an initially incorrect DO interpretation was facilitated by the presence of an implausible NP.

We investigated whether fluent language production is associated with greater skill in resolving lexical competition during spoken word recognition and ignoring irrelevant information in non-linguistic tasks. Native English monolinguals and native English L2 learners, who varied on measures of discourse/verbal fluency and cognitive control, identified spoken English words from dense (e.g., BAG) and sparse (e.g., BALL) phonological neighborhoods in moderate noise. Participants were slower in recognizing spoken words from denser neighborhoods. The inhibitory effect of phonological neighborhood density was smaller for English monolinguals and L2 learners with higher speech production fluency, but was unrelated to cognitive control as indexed by performance on the Simon task. Converging evidence from within-language effects in monolinguals and cross-language effects in L2 learners suggests that fluent language production involves a competitive selection process that may not engage all domain-general control mechanisms. Results suggest that language experience may capture individual variation in lexical competition resolution.

Research among bilinguals suggests a foreign language effect for various tasks requiring a more systematic processing style. For instance, bilinguals seem less prone to heuristic reasoning when solving problem statements in their foreign (FL) as opposed to their native (NL) language. The present study aimed to determine whether such an effect might also be observed in the detection of semantic anomalies. Participants were presented NL and FL questions with and without anomalies while their eye movements were recorded. Overall, they failed to detect the anomaly in more than half of the trials. Furthermore, more illusions occurred for questions presented in the FL, indicating an FL disadvantage. Additionally, eye movement analyses suggested that reading patterns for anomalies are predominantly similar across languages. Our results therefore substantiate theories suggesting that FL use induces cognitive load, causing increased susceptibility to illusions due to partial semantic processing.

Spanish–English bilinguals switched between naming pictures in one language and either reading-aloud or semantically classifying written words in both languages. When switching between reading-aloud and picture-naming, bilinguals exhibited no language switch costs in picture-naming even though they produced overt language switches in speech. However, when switching between semantic classification and picture-naming, bilinguals, especially unbalanced bilinguals, exhibited switch costs in the dominant language and switch facilitation in the nondominant language even though they never switched languages overtly. These results reveal language switching across comprehension and production can be cost-free when the intention remains the same. Assuming switch costs at least partially reflect inhibition of the nontarget language, this implies such language control mechanisms are recruited only under demanding task conditions, especially for unbalanced bilinguals. These results provide striking demonstration of adaptive control mechanisms and call into question previous claims that language switch costs necessarily transfer from comprehension to production.

The multidimensionality of the bilingual experience makes the investigation of bilingualism fascinating but also challenging. Although the literature distinguishes several aspects of bilingualism, the measurement methods and the relationships between these aspects have not been clearly established. In a group of 171 relatively young Polish–English bilinguals living in their first-language environment, this study investigates the relationships between the multiple measures of bilingualism. The study shows that language entropy – an increasingly popular measure of the diversity of language use – reflects a separate aspect of the bilingual experience from language-switching and language-mixing measures. The findings also indicate that language proficiency is not a uniform aspect of the bilingual experience but a complex construct that requires appropriately comprehensive measurements. Collectively, the findings contribute to the discussion on the best practices for quantifying bilingualism.