Investigating crosslinguistic influence (CLI) in L3 morphosyntax through artificial languages

This study investigates the role of structural similarity in third language acquisition by using two different semi-artificial languages (ALs, called Aliensk A and Aliensk N) as the targets and either Polish–Norwegian or Norwegian as the previously acquired languages (all speakers also know English). It is an extension of Mitrofanova et al., who did a similar study with one semi-artificial language with Norwegian, Russian–Norwegian, and Greek–Norwegian speakers. Mitrofanova et al. found that previous experience with a language (Russian) which is structurally similar to the target language is facilitative even in instances where the other previously acquired language (Norwegian) is lexically similar to the target language, but this was only the case when the property in question was both structurally and overtly similar (i.e. had similar overt morphological expression). The ALs in the current study are lexically based on Norwegian, a language which does not have morphological case marking. Aliensk A has case marking on articles (structurally but not overtly similar to Polish) and Aliensk N has case marking on nouns (structurally and overtly similar to Polish). Results provide support for the position that previous experience with a language with an overtly and structurally similar property (case) can be facilitative at early stages of acquisition. However, this process may be mediated by an SVO bias, the level of proficiency and activation of the lexically similar language. Overall, the findings support models of L3/Ln acquisition which consider crosslinguistic influence (CLI) to be the result of co-activation of all previously acquired languages and suggest that both lexical and structural similarity play a role at early stages of acquisition.