Language competition leads to reduced L1 and L2 speech fluency in bilinguals

1.1 Disfluencies in L2 speech For most of us, speaking a second language (L2) is a challenging task. Even if we call ourselves ‘fluent’ in the L2, we may at times find ourselves unsure about the grammar or at a loss for the right words. In fact, we are often not so fluent at all. The most obvious reason for this lack of fluency is a lack of proficiency, that is, a speaker has insufficient knowledge of the L2 and insuffi‐ cient practice in using it. A second important source of interference, however, may be the repre‐ sentations and procedures that we employ in our first language (competition), which are highly accessible and rely on automatic routines that are difficult to suppress. The phenomenon of L2 disfluency is therefore likely to reflect an interaction of L2 proficiency and L1 transfer and com‐ petition, rather than L2 proficiency alone. Here, we will try to isolate and quantify the effect of language competition on fluency. To this aim, we compare the free speech performance of three groups of speakers: monolingual L1 speakers of German in Germany (controls), bilingual speak‐ ers of L1 English/L2 German in Germany (learners) and bilingual speakers of L1 German/L2 English in North America (attriters). The underlying rationale of this comparison is that both groups of bilinguals—learners and attriters—potentially experience interference between the two languages they speak. Yet, incomplete acquisition of the L1 can be ruled out as a factor im‐ pacting on the linguistic behaviour of the L1 attriters. Instead, the disfluencies that we observe in the speech of attriters reflect transfer and competition from the L2.