Theory strongly suggests that L2 perception is influenced by the L1. More recently, it has also been proposed that L2 vocabulary size may be related to the perception of non-native phones. Japanese (JP) learners of Australian English (AE) identified AE vowels using JP vowel categories and provided goodness-of-fit ratings. Results show systematic perceptual assimilations of L2 to L1 vowels and learners with a larger L2 vocabulary provided more consistent identifications.
Bibliographic reference. Bundgaard-Nielsen, Rikke L. / Best, Catherine T. / Tyler, Michael D. (2008): "The assimilation of L2 australian English vowels to L1 Japanese vowel categories: vocabulary size matters", In INTERSPEECH-2008, 1177.