L2 proficiency influence in the perception of lexical stress in Spanish: Ab initio vs. experienced learners

While learners from first languages (L1s) without word stress (e.g. French) often struggle to perceive lexical stress in a second language, some specific L1 prosodic cues (e.g. use of F0 in Korean) may facilitate second language (L2) stress perception. This study investigated how L1 background (French vs. Korean) and L2 proficiency (ab initio vs. experienced) influence Spanish lexical stress perception. Seventy-eight French and Korean learners of Spanish (in two proficiency groups) completed an oddity discrimination task under varying phonetic variability conditions (different talkers and intonation patterns). Results showed that Korean learners significantly outperformed French learners, irrespective of proficiency, suggesting cross-linguistic transfer of F0-based prosodic sensitivity for L2 stress perception. Experienced learners performed better than ab initio learners, indicating that L2 experience facilitates stress perception. However, increased phonetic variability reduced stress discrimination accuracy for all learners, with no interaction between proficiency and phonetic variability. These findings indicate that while L1-specific prosodic background and L2 experience each independently benefit L2 lexical stress perception, advanced learners also struggle under high-variability conditions. The results underscore the importance of accounting for L1 prosodic transfer in second language acquisition and support the use of high-variability perceptual training in L2 instruction to improve learners’ stress perception.