Do bilinguals transfer their L1 knowledge about grammaticality onto L2 structures? What role does L2 proficiency play and do we find overgeneralization effects? To what extent does similarity between L1 and L2 grammar influence the strength of the transfer? All of these questions are broadly related to language transfer effects that have been subject to linguistic research for decades. However, eye tracking technology provides new possibilities to answer these questions more insightfully by exploring the online processing of L2 speakers.

In the present project in collaboration with Holger Hopp (University of Mannheim), we investigate these questions using NP shift structures in English. In English word order, the direct object is typically adjacent to its verb. However, in cases where the object is particularly “heavy“, i.e. long, heavy NP shift permits moving it toward the end of the sentence, allowing other lexical material to intervene between the verb and the object (e.g. Staub et al. 2006):

   - The mother secretly hid the toy.
   - *The mother hid t1 secretly [the toy]1.
        |___________|
- The mother secretly hid the blue toy car with the red top and the green wheels.
- The mother hid t1 secretly [the blue toy car with the red top and the green wheels] 1.  |__________________________|

In German, this surface word order is grammatical no matter whether the NP is heavy or not (“Die Mutter versteckte heimlich das Spielzeug“). The underlying structure reveals that in German, the separation of object and verb is not due to a direct object shift but rather is the result of verb raising.

The surface and structural differences in NP “shift” between German and English make this an ideal structure for testing cross-linguistic influence in the domain of processing. Specifically, we will investigate the extent to which L1 (German) grammatical information is transferred onto L2 (English) processing, using both eye tracking and grammaticality judgment methods.

We also plan to investigate whether L1 transfer depends on L2 proficiency. Most approaches to L1 transfer effects assume that interference is greatest at the lowest levels of proficiency (e.g. Schwartz and Sprouse 1996, Bates and MacWhinney 1987, 1989). NP shift structures are promising for providing insight into this question because the shifting operation is highly rule-based and stylistically marked. These properties are likely to cause German-English bilinguals with low English proficiency to transfer their knowledge of German syntax to English structures because they are unaware of the rule not to separate verb and object in English. This might lead them to accept a wider range of shift instead of only heavy shift. However, one would also expect overgeneralization to affect highly proficient speakers, as they might also apply this rule to heavy NP shift, which would lead them to perceive the exception as ungrammatical as well.

In a previous study, native speakers were tested in an eye tracking experiment and a grammaticality judgment task of the same sentences (to supplement the eye tracking experiment with conscious un-automated decisions about grammaticality). These findings serve as a baseline to which the results of the current project with German-English bilinguals will be compared. Further studies using languages that are typologically more distinct such as Turkish (where objects precede their verbs and adverbial adjuncts usually interfere between them) will be conducted to extend research on the influence of crosslinguistic difference in morphosyntactic structure.