2. Prior reviews of the LMOOC literature

One of the earliest reviews of LMOOC research was Godwin-Jones (Reference Godwin-Jones2014), who concluded that LMOOCs should be treated as an emerging technology that has an impact on both internationalizing and localizing language learning. In the most comprehensive review of LMOOC studies to date, Sallam et al. (Reference Sallam, Martín-Monje and Li2020) identified eight recurring themes of research papers published between 2012 and 2018: (1) conceptualization of LMOOCs; (2) limitations of LMOOCs; (3) exploration of the most suitable models for language teaching; (4) potential of LMOOCs for languages for specific purposes courses; (5) learner-oriented LMOOC research; (6) teacher-oriented LMOOC research; (7) instructional design issues in LMOOCs; and (8) social learning in LMOOCs. It should be noted that the papers reviewed were mostly conference papers. On the one hand, this reflected the fact that the field is relatively new and developing; and on the other, it showed the importance of reexamining the overall trends and major themes in such research, given LMOOCs’ ever-increasing popularity (Jitpaisarnwattana et al., Reference Jitpaisarnwattana, Reinders and Darasawang2021; Lebedeva, Reference Lebedeva2021), amounting even to a kind of LMOOC fever in 2020 (Shah, Reference Shah2020) and the related appearance of many more high-quality LMOOC studies in the field.

5. Future directions for LMOOC research

Based on the identified nine key LMOOC research topics and the changes in the popularity of those topics over time, this section provides detailed recommendations for future LMOOC research, including for subtopics within each topic, research designs, data-analysis approaches, and theoretical underpinnings.

Topic 1: Core elements of LMOOCs. Although our ThemeRiver diagram shows a decreasing trend in this research topic’s popularity, understanding LMOOCs’ core elements is still vital. Future researchers should obtain a more thorough understanding of each LMOOC course object in isolation. Usually, course elements in LMOOCs follow the xMOOC approach closely, and can be divided into two general types: video lectures and supporting materials. In the case of the former, the successful design and production of videos will directly impact LMOOC students’ perceptions of their learning. Sokolik (Reference Sokolik, Martín-Monje and Bárcena Madera2014) also suggested that videos in LMOOCs should reflect outside-the-box thinking, and that one of many options for achieving this is to make authentic story-based language learning videos. Nevertheless, the present systematic review of 71 studies found only one (Ge, Liang & Peng, Reference Ge, Liang and Peng2021) that examined the videos used in LMOOCs. Filling this surprising gap in the literature is a clear and important avenue for future research.

Besides videos, supporting materials such as class slides, supplementary audio and video resources, text files, and external links are commonly supplied within LMOOCs. However, none of these specific elements were adopted as research objects by the studies we sampled, perhaps because many of those studies’ authors seemed to regard them as a single package (e.g. Castrillo & Sedano, Reference Castrillo and Sedano2021; Zancanaro & Domingues, Reference Zancanaro and Domingues2018). We therefore call for a more thorough understanding of each of the course objects in LMOOCs.

Topic 2: Interaction and communication in LMOOCs. More research is needed to explore effective ways to enhance both learner–learner and learner–instructor interaction, especially amid the rise of innovative and intelligent communicative tools such as instant voice, text messages, and social media posts as aids to traditional LMOOC learning (Lebedeva, Reference Lebedeva2021). After all, LMOOCs are not only about the “goal” of learning but also about the “vehicle” (Bárcena, Read & Sedano, Reference Bárcena, Read and Sedano2020: 39). It is therefore vital to set the promotion of interaction as “a specific e-literacy goal” (Wright & Furneaux, Reference Wright and Furneaux2021: 33); indeed, such literacy should become an integral part of online-learning instructional design in general.

In addition, the impact of the promotion of interactivity within LMOOCs warrants further study. This is because, on the one hand, LMOOCs are designed to be learner centered and social (Bárcena, Read, Martín-Monje & Castrillo, Reference Bárcena, Read, Martín-Monje, Castrillo, Cress and Delgado2014) and, on the other, because studies have found some learners treat such courses as resource banks, or even monologic learning spaces (Hsu, Reference Hsu2021a; Mac Lochlainn et al., Reference Mac Lochlainn, Nic Giolla Mhichíl and Beirne2021). Scholars have also critiqued LMOOCs for their lack of face-to-face interaction (Mellati & Khademi, Reference Mellati and Khademi2020; Uchidiuno et al., Reference Uchidiuno, Ogan, Yarzebinski and Hammer2018). This, as Mac Lochlainn et al. (Reference Mac Lochlainn, Nic Giolla Mhichíl and Beirne2021) pointed out, suggests the need for scholars to debate whether it matters “if learners view LMOOCs as a means of furthering their offline goals rather than fostering virtual communities” (p. 123; see also Hsu, Reference Hsu2021a). In short, even though social interaction is vital to learning, there should be more empirical studies about the interrelationship of enrollment type, interaction, and learning outcomes, especially ones that take account of potential moderators and/or mediators of that interrelationship at the course, teacher, student, cultural and/or other contextual levels.

Topic 3: Innovative LMOOC teaching practices. Based on the insight that taking LMOOCs on mobiles is not identical to doing so on personal computers (Moreno & Traxler, Reference Moreno and Traxler2016), one potential future direction for studying innovative teaching practices in LMOOCs involves the perspective of mobile-assisted language learning (MALL) on both instructional design and teaching methodologies. Yet only one study we reviewed adopted a MALL framework (Read & Bárcena, Reference Read and Bárcena2020).

A second direction involving this topic would be to explore more individualized LMOOCs with multiple learning paths. Consistent with Anderson, Huttenlocher, Kleinberg and Leskovec’s (Reference Anderson, Huttenlocher, Kleinberg, Leskovec and Chung2014) classification of MOOC learners into five types – that is, viewers, all-rounders, solvers, bystanders, and collectors – individual LMOOC students exhibit a variety of both learning behaviors (e.g. Hsu, Reference Hsu2021a; Mac Lochlainn et al., Reference Mac Lochlainn, Nic Giolla Mhichíl and Beirne2021; Martín-Monje, Castrillo & Mañana-Rodríguez, Reference Martín-Monje, Castrillo and Mañana-Rodríguez2018) and learning sequences (Jitpaisarnwattana et al., Reference Jitpaisarnwattana, Reinders and Darasawang2021). In this sense, compulsory tasks that require learners to submit uniform and rigid answers are arguably inappropriate to the LMOOC setting (Martín-Monje et al., Reference Martín-Monje, Castrillo and Mañana-Rodríguez2018), and should be replaced by more flexible options that take account of variation in learners’ educational and cultural backgrounds (Bárcena & Read, Reference Bárcena and Read2015).

A third direction would be to reconceptualize assessment activities. Previous studies have reported inconsistent results regarding the effects of LMOOCs’ adoption of self-assessment, peer assessment, and assessment by computers or artificial intelligence tools (e.g. Suen, Reference Suen2014). Also, given that most students’ interest and motivation to participate in a given course is likely to diminish over time, it is important for LMOOC providers to consider adopting more innovative and effective assessment activities (Hashim, Salam, Mohamad & Sazali, Reference Hashim, Salam, Mohamad and Sazali2018; Sokolik, Reference Sokolik, Martín-Monje and Bárcena Madera2014, Reference Sokolik, Martín-Monje, Elorza and Riaza2016; Uchidiuno et al., Reference Uchidiuno, Ogan, Yarzebinski and Hammer2018).

A fourth direction involves thinking outside the box. Specifically, although LMOOCs can be carried out in either xMOOC or cMOOC formats, and “many consider cMOOCs to be superior [to xMOOCs] in form and function” (Sokolik, Reference Sokolik, Martín-Monje and Bárcena Madera2014: 18), almost all LMOOCs so far have been xMOOC oriented, centering on a specific topic and mirroring formal learning (Martín-Monje et al., Reference Martín-Monje, Castrillo and Mañana-Rodríguez2018). It would be hard to argue against the idea that LMOOCs should provide something more than a lecture-based, instructor-centered approach – for example, encourage those taking them to set up on their own personalized learning networks (Godwin-Jones, Reference Godwin-Jones2014). Clearly, future studies exploring how cMOOC-based or other new formats of LMOOCs can be effectively designed and utilized are warranted.

Topic 4: Standards and quality assurance in LMOOCs. Many studies have made important contributions to our understanding of what constitutes an effective LMOOC course (e.g. Chacón-Beltrán, Reference Chacón-Beltrán2017; Fang, Reference Fang2018; Friðriksdóttir, Reference Friðriksdóttir2021; Read & Bárcena, 2020; Sokolik, Reference Sokolik, Martín-Monje and Bárcena Madera2014). However, all of them have lacked clear, detailed, theoretically and empirically grounded rubrics that capture a range of dimensions of LMOOC design and teaching. Creating one could represent an important new research direction, especially if the resulting rubric is easy for LMOOC educators to use. In short, as Luo and Ye (Reference Luo and Ye2021) pointed out, “as millions of people learn from LMOOCs and millions of dollars are invested in LMOOCs every year, there is a pressing need to establish benchmarks for quality assurance” (p. 178). In this context, it is also worth noting that the data used in most previous studies of LMOOC quality and standards have been drawn from these course creators’ experiences and reflections rather than from learners’ perspectives – an imbalance that future studies should redress.

Topic 5: LMOOC implementation, participation, and completion. Further research on this topic should, in the first instance, continue exploring how best to develop specific language skills within LMOOCs. Past studies have suggested that LMOOCs can be effective for the development of receptive skills such as reading and listening, but much less so for productive skills such as speaking and writing (Sallam et al., Reference Sallam, Martín-Monje and Li2020). Our finding that the two most popular language skills (apart from integrated skills) were both productive (i.e. speaking and writing) may suggest that LMOOC researchers are already making the necessary efforts in this direction. On the other hand, at just 15.5% of the total sample, the quantity of such studies is still limited, and more are clearly warranted – especially those that take account of obstacles to productive-skill acquisition that may be posed by course logistics.

Secondly, future LMOOC research on this topic needs to explore best practices for delivering culture-related content (Colibaba et al., Reference Colibaba, Dinu, Gheorghiu, Colibaba and Grosu-Rădulescu2018; Fuchs, Reference Fuchs2020; Luo & Ye, Reference Luo and Ye2021; Mac Lochlainn, Nic Giolla Mhichíl & Beirne, Reference Mac Lochlainn, Nic Giolla Mhichíl and Beirne2020a; Mac Lochlainn, Nic Giolla Mhichíl, Beirne & Brown, Reference Mac Lochlainn, Nic Giolla Mhichíl, Beirne and Brown2020b). Our review found that only four out of 71 studies studied culture-focused LMOOCs, and their treatment of such courses’ instructional design was especially limited. Given the capability of LMOOCs to provide learners with authoritative materials, it is of great importance for future LMOOC research to discuss how teaching objectives, learning content, learning activities, and assessments that cater to different LMOOC study contexts can work synergistically in the delivery of cultural content.

A third promising avenue for research on this topic involves the teaching of LMOOCs for specific purposes, which, although relatively new (Sokolik, Reference Sokolik, Martín-Monje, Elorza and Riaza2016), look likely to grow in popularity, perhaps even more quickly than LMOOCs as a whole (see also Uchidiuno et al., Reference Uchidiuno, Ogan, Yarzebinski and Hammer2018). Nevertheless, only seven out of our 71 sampled studies examined the LMOOCs for EAP or ESP. Further studies involving the specific purposes of LMOOCs are therefore to be welcomed, and in particular, our results suggest that they should (1) seek more innovative pedagogical possibilities for accommodating language learners’ needs rather than focusing on traditional course tools, such as dictionaries, translators, or interactive transcripts; (2) study how to facilitate students’ acquisition of dual learning outcomes – for example, both medical knowledge and medical linguistic communication skills (Colibaba et al., Reference Colibaba, Dinu, Gheorghiu, Colibaba and Grosu-Rădulescu2018); and (3) give due attention to issues around the building, within LMOOCs for specific purposes, of learning communities that can facilitate both knowledge creation and collaboration (Sokolik, Reference Sokolik, Martín-Monje, Elorza and Riaza2016).

Another fourth direction for the study of T5 is the localization and globalization of LMOOCs. Language learners can, of course, enroll directly in LMOOCs provided by countries where their target language is spoken (Doğan, Sunar, Duru & White, Reference Doğan, Sunar, Duru and White2018). In practice, however, this does not always happen, and 41 of the 71 studies we reviewed focused on LMOOCs provided by local institutions, such as Chinese instructors teaching English. Many of these localized courses were designed around the goal of providing more indigenized learning to learners in the countries where they were hosted. Therefore, it is important to conduct some direct comparative studies of LMOOC learning that situate course providers, teachers, teaching pedagogies, teaching beliefs, teaching contents, and students in different cultural contexts.

Topic 6: LMOOC teaching planning. We argue that this topic needs to be escalated into a broader one covering teachers and teaching in LMOOCs. The first new research direction suggested by such an expanded viewpoint involves teacher training. Future studies could usefully focus on (1) best practices in LMOOC teacher training (King, Luan & Lopes, Reference King, Luan and Lopes2018; Kormos & Nijakowska, Reference Kormos and Nijakowska2017); (2) adaptations to diverse cultural groups and learners with specific needs (Kormos & Nijakowska, Reference Kormos and Nijakowska2017); and (3) teacher training based on interventions in teachers’ beliefs, autonomy, roles, and awareness, online teaching and learning theories, and specific online-activity designs (Castrillo, Reference Castrillo, Martín-Monje and Bárcena Madera2014; King et al., Reference King, Luan and Lopes2018; Koukis & Jimoyiannis, Reference Koukis and Jimoyiannis2019; Orsini-Jones, Zou, Hu & Wei, Reference Orsini-Jones, Zou, Hu and Wei2017; Phi, Reference Phi2017).

In addition, there has been little study to date of interaction among the multiple stakeholders in LMOOC design and teaching, despite the critical importance of extensive and close stakeholder collaboration to such courses’ success (Castrillo & Sedano, Reference Castrillo and Sedano2021; Zancanaro & Domingues, Reference Zancanaro and Domingues2018). What might be called the ecological sphere of these stakeholders includes, but is not limited to, learners, teaching assistants, universities, NGOs and other support associations.

Another direction for T6 research is the integration of LMOOCs into traditional classroom teaching. Although seven out of the 71 sampled studies focused on the use of LMOOCs as small private online courses, the conclusions of this research stand would be more reliable, valid, and nuanced if it examined additional languages, proficiency levels, language skills, and cultural backgrounds.

Topic 7: LMOOCs’ learning effectiveness and its factors. Various factors such as motivation, demotivation, self-regulation, anxiety, the Big Five personality traits, and learning styles were identified in the collected literature as key differences (e.g. Agonács et al., Reference Agonács, Matos, Bartalesi-Graf and O’Steen2019; Hsu, Reference Hsu2021a, Reference Hsu2021b). As Ding and Shen (Reference Ding and Shen2019) pointed out, much more research attention should be paid to the psychological and behavioral dimensions of LMOOC learners’ autonomous behavior, and especially to how/why they adopted their autonomy, heutagogy, self-determination, self-efficacy, and use of metacognitive, motivation-control and emotional-control strategies.

Topic 8: Learners and learning in LMOOCs. Arguably, the most promising future direction in T8 research involves learner behavior. To date, many studies have been based on behaviors that can be recorded and tracked on learning platforms. However, behaviors other than those that such platforms can document certainly exist, and could be important reflections of the social dimension of learning. For example, Mac Lochlainn et al. (Reference Mac Lochlainn, Nic Giolla Mhichíl and Beirne2021) found that as well as writing or recording their own target-language output as their LMOOC required, learners were listening to and even assessing the target-language output of their peers. In light of such complex behavioral dynamics, future LMOOC studies should actively seek out learning behaviors that are not recorded by learning platforms and/or that were not envisioned or encompassed by courses’ initial designs.

Another potentially fruitful direction for future research on this topic is to attempt to understand LMOOC learners holistically as people, in line with Ushioda’s (Reference Ushioda2011) argument that language learners should be understood holistically rather than simply as learner types (see also Martín-Monje & Borthwick, Reference Martín-Monje and Borthwick2021). Specifically, this would require analysis not only of LMOOC learners’ course-related data, such as their grades, but also of their relationships with their environmental contexts at both micro and macro levels.

Finally, future T8 researchers should study post-LMOOC learning. Language learning is a relatively long process, and language proficiency needs to be regularly or continuously topped up as part of a lifelong learning process. Chacón-Beltrán (Reference Chacón-Beltrán2017) noted that the beginning-level learners of English that he studied received explicit instruction on how to continue their English learning after completing their LMOOC. We expect that many existing LMOOCs offer such instruction, either explicitly or implicitly, through videos or discussions. However, none of the studies we sampled focused on this phenomenon.

Topic 9: Inclusiveness in LMOOCs. Recent studies point to the possibility of using LMOOCs to provide equitable, socially inclusive forms of language learning (e.g. Meri-Yilan, Reference Meri-Yilan2020; Rodrigo, Reference Rodrigo, Martín-Monje and Bárcena Madera2014). Nearly 10% of our collected studies were of LMOOCs geared toward populations widely seen as marginalized by mainstream education, including refugees (e.g. Bárcena et al., Reference Bárcena, Read and Sedano2020; Castrillo & Sedano, Reference Castrillo and Sedano2021), people with dyslexia (Kormos & Nijakowska, Reference Kormos and Nijakowska2017), low-proficiency adults (López, Reference López2019), and senior citizens (Mac Lochlainn et al., Reference Mac Lochlainn, Nic Giolla Mhichíl and Beirne2020a, 2021). LMOOC education for these groups should be carefully contextualized. Accordingly, research that takes account of LMOOC students’ unique combinations of cultural background, educational level, and learning styles should be strongly encouraged.

However, inclusiveness in LMOOCs does not merely involve learners’ characteristics but also the representation of minority languages. All the LMOOCs studied by our 71 sampled studies collectively taught only 13 target languages. More broadly, it is undeniable that most current LMOOCs reflect a Western-oriented epistemology (e.g. Bárcena et al., Reference Bárcena, Read and Sedano2020). But, as Mac Lochlainn et al. (Reference Mac Lochlainn, Nic Giolla Mhichíl, Beirne and Brown2020b) pointed out, the true potential of MOOCs is “not only enablement or enhancement but also the possibility of empowerment” (p. 212). Lack of research on the social justice, inequality and diversity implications of LMOOCs could make it impossible to achieve the goal of empowerment (Meri-Yilan, Reference Meri-Yilan2020), or worse, deepen inequality because “MOOC producers are firmly moored in the global North and critics argue that MOOCs reproduce neo-colonial, hegemonic educational practices” (King et al., Reference King, Luan and Lopes2018: 285). This would obviously deviate from the original conception of MOOCs as reaching those “underprivileged people who cannot access regular paid education and are often in precarious, unstable situations” (Bárcena et al., Reference Bárcena, Read and Sedano2020: 39). Researchers should therefore investigate the existing barriers to LMOOCs’ inclusion of more languages, especially minority ones and non-Western epistemologies, and propose concrete ways of overcoming such barriers.

Research design. Design-focused research (Appel & Pujolà, Reference Appel and Pujolà2021) was not identified as a distinct LMOOC research topic by LDA. Yet in spite of, or because of, this absence, more such research is clearly also needed. As Levy (Reference Levy, Rodriguez and Pardo-Ballester2013) commented, a design-based approach could “provide one pathway forward to CALL, particularly because of its engagement, from the outset, with the concerns of the practitioner and their interaction with systems” (p. 38). It is through an iterative process of interchange between practitioners and researchers that the instructional designs of LMOOCs are best refined (Appel & Pujolà, Reference Appel and Pujolà2021). In addition, grounded-theory research that engages in “granular analysis of activities” (Mac Lochlainn et al., Reference Mac Lochlainn, Nic Giolla Mhichíl and Beirne2021: 113), and uses the results to generate concepts and theories particular to LMOOC learning, is strongly needed (Hsu, Reference Hsu2021a).

Data analysis. The two general foci of this future work should be big data and small data. With regard to the former, methods including data mining, learning analytics and machine learning are promising (e.g. Friðriksdóttir, Reference Friðriksdóttir2021; Zeng et al., Reference Zeng, Zhang, Gao, Xu and Zhang2020). As for small data, content-analysis, case-study, and/or autoethnographic methods may be effective ways to document and trace LMOOC educators’ actions, reflections and changes. In particular, we believe that autoethnographic approaches (Ellis, Reference Ellis2004) could contribute vital new knowledge to the field of LMOOC teaching and learning.

Theoretical foundations. Our review identified 25 theoretical constructs that had been adopted by scholars examining LMOOC design and/or implementation. Among these, the most popular were motivation, heutagogy, and learning autonomy. This is not surprising as, by their nature, MOOCs require learners to be autonomous and self-motivated. Like Sallam et al. (Reference Sallam, Martín-Monje and Li2020), we are eager to see future studies that use more diverse and influential theories and concepts drawn from applied linguistics and general educational psychology. On the other hand, there should also be more self-regulated learning-related topics in LMOOC research. This has to do with both the high impact of self-regulated learning research in applied linguistics, and the nature of LMOOCs themselves, as enabling self-regulated language learning.

6. Limitations

This study has the following limitations. First, because it focused on published papers in peer-reviewed journals and book chapters, it may have missed important trends and topics in LMOOC research that appeared only in conference proceedings, dissertations and theses. Also, our review was limited to publications in English.