Lexical Adaptation in Spanish: Implications for phoneme-specific and stress-dependent learning trends

Perceptual learning is a well-established phenomenon in phonetics literature. Listeners are typically able to hear novel speech patterns, attune their perception, and process speech at very rapid rates. Nonetheless, there are some factors that may decrease the rate and efficiency at which this happens, such as accentedness, the presence of multiple speakers, and social factors. This study investigates the learning of a vowel chain shift in Mexican Spanish across two experiments. The reason for choosing Spanish listeners, is that (1) Spanish has a different vowel space than English, and (2) Spanish dialectal variation is not typically realized through differences in vowel realizations, thus Spanish listeners do not experience vowel shifts regularly. Both experiments have participants listen to a story with a vowel shift proceeded by a lexical decision task. The results of this experiment show different learning and word endorsement rates across the different vowels. Additionally, no effects of trained words were found. The results of this study were also compared to previous work on perceptual learning, showing potential language differences. Overall, the results of this study show relevance to perceptual learning and to the rapid adjustment of phonemic boundaries.