Training Korean listeners to perceive phonemic length contrasts in Japanese: Effects of speaking rate variation and contrast type

Abstract

Japanese phonemic length contrasts are difficult to perceive for native-Korean listeners learning Japanese as a second language (L2). Aiming at an effective L2 training method for L2 learners, two experiments were conducted. Experiment 1 evaluated which acoustic cues Korean listeners rely on when categorizing the phonemic length contrast. Experiment 2 examined how differences in speaking rate variation (slow, normal, and fast) and contrast type (vowel contrast vs. consonant contrast) would affect the effectiveness of perceptual training, using a minimal-pair identification task with words embedded in carrier sentences. There were four training conditions comprising combinations of two contrast types (vowel or consonant length) and two speaking-rate variations (single rate or three different rates). Results show that L2 listeners exploit absolute segmental duration to identify phonemic length contrast rather than durational criteria that vary according to speaking rate. Moreover, the trained groups signifi...