This study investigated the contribution of second-language (L2) phonetic categorization abilities and vocabulary size to the phonolexical encoding of challenging non-native phonological contrasts into the L2 lexicon. Two groups of German learners of English differing in L2 proficiency (advanced vs. intermediate) participated in an English lexical decision task including words and nonwords with /ɛ/ and /æ/ (/æ/ does not exist in German), an /ɛ/-/æ/ phonetic categorization task and an English vocabulary test. Results showed that the effects of phonetic categorization and vocabulary size on lexical decision performance were modulated by proficiency: categorization predicted /ɛ/-/æ/ nonword rejection accuracy for intermediate learners, whereas vocabulary did so for advanced learners. This suggests that sufficient phonetic identification ability is key for an accurate phonological representation of difficult L2 phones, but, for learners for whom robust phonetic identification is already in place, their ultimate success is tightly linked to their vocabulary size in the L2.

There is growing evidence that the orthographic forms (spellings) of second language words affect second language (L2) speech production, but it is not known whether orthography affects L2 phonology in native users of a non-alphabetic writing system. To answer this question, this study tested the effects of number of letters on the duration of consonants and vowels in the EnglishL2 speech production of Japanese–English sequential bilinguals. JapaneseL1–EnglishL2 bilinguals and English native speakers (both n = 16) performed a delayed word repetition task, producing 16 English word pairs in which the same consonant or vowel was spelled either with a single letter or with double letters, as in city-kitty. The bilinguals produced the same English sound as longer or shorter depending on the number of letters in its spelling, confirming that L2 orthographic forms affect L2 speakers’ phonological representations of L2 words even when their L1 writing system is not alphabetical.

While considerable dialectal variation exists, almost all varieties of Spanish exhibit some sort of alternation in terms of the palatal obstruent segments. Typically, the palatal affricate [ɟʝ] tends to occur in word onset following a pause and in specific linear phonotactic environments. The palatal fricative [ʝ] tends to occur in syllable onset in other contexts. We show that listeners’ perceptual sensitivity to the palatal alternation depends upon the task and exposure to Spanish input. For native Spanish listeners, the palatal alternation boosts segmentation accuracy on an artificial speech segmentation task and also reduces latencies on a phonotactically-conditioned elision task. L2 Spanish listeners, on the other hand, only benefit from the palatal alternation in the second task. These results suggest that while Spanish L2 learners benefit from the presence of the alternation in linear phonotactic terms, this benefit does not carry over to a more abstract segmentation task.