Perceptual training enhances Seoul Korean listeners’ use of vowel quality and pitch cues to English lexical stress

This study investigates whether high-variability (multi-talker) perceptual training is superior to low-variability (single-talker) perceptual training for enhancing Seoul-Korean listeners’ use of vowel quality and pitch cues to English lexical stress. Vowel quality and pitch are the two most important cues to English lexical stress in accented words (Tremblay et al., 2021). Seoul Korean does not have lexical stress, lexical pitch accents, or lexical tones. Seoul-Korean listeners completed a pre-/post-test sequence-recall experiment where they heard and recalled four English words uttered by different talkers. Experimental conditions: The words differed in lexical stress, which was cued by: (i) vowel quality, pitch, and duration; (ii) vowel quality and duration; (iii) pitch and duration; or (iv) duration. Control condition: The words differed in their initial consonant (Seoul-Korean contrast). Listeners completed one of two training types (8 × 30-mins). The words in the training followed a cue distribution that mimicked naturalistic spoken English (Im et al., 2018). Results: Both training types improved listeners’ recall for (i)–(iii), suggesting enhanced use of vowel quality and pitch. Learning gains were greater with high-variability training, but training type did not interact with cue. Thus, high variability provides a global rather than selective enhancement of listeners’ use of cues to lexical stress.