Phonological (in)visibility

Reduced vowels between obstruents and rhotics are durationally variable and phonologically invisible in Spanish, e.g. p ə rado ‘field’ as /pɾ/. The present study compares L1-Spanish speakers, English monolinguals, and L2-Spanish learners’ perceptual boundaries for reduced vowels in Spanish. A native speaker produced 70 Spanish nonce words with word-initial obstruent + vowel + flap sequences, and the duration of each vowel was manipulated from 100% to 75%, 50%, and 25% of its original duration. To determine whether these groups perceive variably reduced vowels as phonologically visible, 78 listeners counted the number of syllables perceived in 280 target audio files. Linear regression models fitted to 21,436 responses indicate that English monolinguals apply an L1 perceptual strategy, but L2-Spanish learners have shifted their perceptual boundaries. The study concludes that the perception of highly variable acoustic information becomes more native-like with greater L2 proficiency, while age of acquisition is less predictive of native-like perception.