Experimental contributions of eye-tracking to the understanding of comprehension processes while hearing and reading code-switches

Researchers who study code-switching using lab-based approaches face a series of methodological challenges; these include, but are not limited to, using adequate techniques and tasks that allow for processing that reflects real-language usage and selecting stimuli that reflect the participants’ code-switching community norms. We present two illustrative eye-tracking studies that consider these challenges. Study 1 tests whether experience with code-switching leads to differential processing of Spanish determiner-English noun code-switches (e.g., una cookie ‘a cookie’). Study 2 examines auxiliary-verb code-switches involving the progressive structure (e.g., están cooking ‘are cooking’) and perfect structure (e.g., han cooked ‘have cooked’) while participants read either for comprehension or provide grammaticality judgments. The results of both studies highlight the advantages that eye-tracking provides when its use is accompanied by an appropriate bilingual sample, by stimuli that reflect actual bilingual language use, and by secondary tasks that do not invoke metalinguistic processes.