The non-selective view of language access proposes that for bilinguals, both languages are active to a certain extent, and the degree to which these languages are active depend on a variety of factors (e.g. proficiency) (Gollan & Ferreira, 2009; Kroll et al., 2006, Macizo et al., 2012). This dual activity is evident when bilinguals code-switch. Code-switching occurs when bilinguals shift from one language to another while speaking. This switch can occur for a single word, phrase, sentence, or more; and may occur for a variety of reasons (Baker, 2001; Heredia & Altarriba, 2001). While many studies have examined language switching with controlled laboratory stimuli, fewer studies have explored this phenomenon in a more naturalistic conversational setting.

The current study builds on previous research that examines whether the presence of a monolingual English speaker can induce code-switching. German-speaking bilinguals were recruited to participate and complete an interview in German lasting approximately 30 minutes. Using random assignment, the interviews of half of the participants were interrupted by a monolingual English-speaking research assistant who only spoke to the interviewer. After the interruption, the research assistant stayed in the room for the remainder of the interview. The participants in the control group completed the interview without interruption. Following the interview, all participants completed a language questionnaire. Code-switching behavior was compared between the participants who were interrupted to those who were interviewed without interruption. Additional factors such as linguistic background and language proficiency were examined.