Language switching and mixing are two distinct phenomena, which correlate to different expressive behaviors. It is in general agreement that language switching is inter-sentential, the alternation of languages across sentences or clause boundaries, while language mixing is intra-sentential, the incorporation of linguistic units (e.g. word, syllable, morphemes, phonemes) from one language (e.g. L2) into a sentence or a sequence of sentences (e.g. narrative discourse or conversation) in another language (e.g. L1) (Sridhar & Sridhar, 1980; Bokamba, 1989;
Kamwangamalu, 1992; Myers-Scotton, 1993; Fabbro, 2001b). The examples for the inter-sentential and intra-inter-sentential switching are collected from Lyu et al. (2015) on Mandarin-English bilingual are illustrated as follows (to differentiate between two languages, one of the languages is represented in italic format)
1. Inter-sentential switching
Mandarin-English bilingual: Lyu et al., 2015
很容易罷了。Put the pumpkin in, fried it then add the chicken stock.
It’s very easy. Put the pumpkin in, fried it then add the chicken stock.
2. Intra-sentential switching
Mandarin-English bilingual: Lyu et al., 2015 我今天想去 Starbucks 買一杯 ice-coffee.
I am thinking of going to Starbucks to buy a cup of ice-coffee.
However, there is a difference of opinions as to whether the distinction between language switching and mixing is truly necessary. Hatch (1976) argued that these two phenomena do not have sharp distinction and should treat them as the same. Some scholars also suggest to focus the language switching and mixing performance of speakers on the discourse and interactional functions and thus refer them as situational shifting, a tendency to switch by a change in situation (Gumperz, 1982; Pakir, 1989; Tay, 1989). On the other hand, others felt a need to distinguish them especially on the details of the grammatical structure (Kachru, 1978;
McLaughlin, 1984; Bokamba, 1989). Therefore, this study hopes to unravel this confusion through exploring the underlying brain mechanisms of bilinguals in comprehending the language switching and mixing sentences.
Based on linguistic corpora, linguistic theories are generated into predictive hypotheses to unravel the underlying linguistic and cognitive mechanisms in language switching and mixing.
The current study will discuss the triggering hypothesis proposed by Clyne (1967, 2003). Clyne found out that the immigrants in Australia (German, Dutch, Hungrian, Italian, Spanish, Croatian, and Vietnamese) tend to code switch when a sentence contains one or more cognates.
More specifically, cognate, including proper nouns and homographs, will trigger code switching to another language. Cognates are words that are related in origin to another word, and usually have similar meanings and spellings in different languages (e.g. tennis share the similar meaning and spelling in English and Croatian). In addition, Clyne (1967) differentiated
three forms of triggering loci: the sequential facilitation (where the code switched takes place after the trigger word), the anticipational facilitation (where the code switch precedes the trigger word) and the combination of these two (where the code switch is in the middle of these two trigger words). Therefore, the triggering mechanism suggested that the existence of cognates will first co-activate both languages in a bilingual and thus facilitate the code switch to another language. However, this hypothesis raised much debate as it is not put into statistical test and might be tagged as pure coincidence upon the arrival of these predictions from his corpus data.
Broersma and De Bot (2006) tested the triggering hypothesis in their corpus study by analyzing several cognates and code switch conversations in Dutch-Moroccan Arabic bilinguals. Their statistical test of the code switching patterns found support for part of the original triggering hypothesis, which states that the cognate acts as a trigger to facilitate the code switch. However, the data were best explained in the adjusted triggering hypothesis, which suggested that the triggering takes place in the same clause and occurs before the surface structure is formed, in the lemma level. A trigger word in language X can cause a shift of activation in another language (the unintended language), for instance, the language Y, thereby causing the lemmas in language Y to be activated and thus increased the chances to be selected.
Subsequent research (Broersma, 2009; Broersma et al., 2009) on the corpus analysis of Dutch
immigrants in New Zealand and Australia reported that higher frequency of code switching patterns was observed in clauses containing a cognate.
To reveal the underlying processing mechanisms in triggering code switching, Kootstra et al. (2012) investigated the triggering hypothesis under natural dialogue situation by means of confederate-scripted priming technique. This technique involved two participants that were
instructed to describe pictures that were presented on a laptop. One of the participants was a confederate, who followed the instructions assigned by the experimenter and whose linguistic behavior was scripted. The other was the “real” participant, unknowingly aware of the identity of the other participant that the confederate’s dialogue to code switch or not was scripted. The main purpose was to examine whether the manipulation of switched or non-switched utterances of the confederate would influence the “real” participants to code switch. The overall result concluded that the immersion in a code switching discourse situation would consequently influence the lexical triggering of code switches. In addition, cognate words would co-activate bilingual’s syntactic representations in both languages and facilitate the syntactic integration of multiple languages into one sentence.
Finally, several experimental studies with nouns as cognate triggers discovered that cognate lexical (noun) functioned as triggers in promoting the code switching process (Broersma, 2011;
Kootstra et al., 2012). It is therefore questioned whether verb cognate would pose similar trigger as the noun cognate. Studies have reported that cognate verbs do not facilitate the
triggering effect in switching languages and that, cognate verbs rarely have similar orthography and phonology forms Bultena et al., 2012.
In sum, the above studies suggest that the involvement of cognate words would facilitate the triggering of language switching. In addition, if provided with a discourse situation where high frequency of code mixing occurred, it is plausible to have the lexical triggering effect to code switch into another language. Finally, the facilitation process of code switching to another language is restricted to noun cognates.