Phonological change in Slovene-English late consecutive bilinguals

Within the individual, one possible cause of sound change in a given language is the acquisition of another language. In recent years, there has been a shift in studies of bilingualism, as linguists have started to investigate not only the influence of a first language (L1) on a second language (L2), but also the impact of L2 on L1. Following the Speech Learning Model (Flege 1987), changes in the L1 production of bilinguals would happen at the level of individual phonemes, so that some sounds may become more similar to L2 equivalents, while others become more dissimilar. According to Chang’s (2012) model of phonetic drift, on the other hand, changes happen at the level of the system as a whole. The present study aims to test the predictions of L1 and L2 theories with reference to the L1 production of late consecutive Slovene-English bilinguals. Seventeen Slovene-English bilinguals, who acquired Slovene language in childhood and moved to England in late adolescence or adulthood, were recorded reading word lists and passages in English and Slovene, which had been selected to include all the vowel sounds of the two languages. The recordings were analysed acoustically, and the vowel formant frequencies were compared with similar data from monolingual speakers of Slovene and English. To relate the acoustic data with perceptual evidence, monolingual speakers of both languages listened to the recordings of the target bilingual group and rated the degree of foreign-accentedness. The aim was to predict the extent of any changes in the bilinguals’ Slovene speech, relative to Slovene monolinguals, on the basis of intralinguistic factors, e.g. similarity between particular sounds in the two languages, and extralinguistic factors, e.g. age at arrival in the UK. The results of the production experiment indicated that the extracted vowel formant frequencies (F1, F2 and F3) of bilinguals to some extent differ from monolingual norms. Additionally, some evidence that L1 sound change does take place was evident in the analysis of individual vowel sounds and corroborated by the global accent rating task (GAR), since the Slovene monolingual speakers tended to rate the bilinguals as non-native speakers of Slovene. The degree of changes in L1 was also correlated with extralinguistic factors of AOA and LOR.