The influence of L2 experience on L1 speech perception: Evidence from Mandarin-English bilinguals

Aims: Previous studies have documented that consonants contribute more to lexically related processes than vowels in English, whereas an opposite pattern occurs in Mandarin Chinese processing. The current study aims to examine how the long-term learning of English (L2) influences Mandarin (L1) consonant, vowel, and tone perception in bilingual adults. It also attempts to examine the multi-competence theory at the level of speech perception. Methodology: A total of 73 Mandarin-English bilinguals with different L2 proficiency levels performed the L1 syllable perception task in an active oddball paradigm. The deviant syllables differed from the standard in consonant, vowel, or tone. Participants were asked to press a button whenever they heard a different syllable. Data and analysis: The reaction time and accuracy of each deviant syllable were recorded by E-prime 2.0. These data were analyzed using mixed-effects models. Findings/conclusions: Results showed that the relative role of vowel was the strongest, followed by consonant, and then by tone in L1 speech perception. The pattern of their relative roles/phonological bias was not influenced by L2 proficiency, indicating that the phonological bias in L1 speech perception is not affected by a transfer from non-native to native processing, but determined by the acoustic/phonological cues and lexical information carried by consonant, vowel, and tone. However, the perceptual sensitivity to L1 speech increased with L2 proficiency, demonstrating a positive L2 effect on L1 at the level of speech perception. Originality: The current study first investigated the influence of L2 experience on L1 phonological bias in bilinguals whose first and second languages were typologically distant. Significance/implications: Our findings lend support to the multi-competence theory and extend it to the level of speech perception.