Is allophonic variation in Japanese /ɾ/ a factor in Japanese listeners’ difficulty in perceiving English /ɹ-l/?

Abstract

Japanese listeners’ difficulty in perceiving the English liquid (/ɹ-l/) contrast has been attributed to various phonological and phonetic factors. To explore allophonic variation in the Japansese flap as a contributing factor, American English listeners’ perception of Japanese /ɾ/ was investigated in a range of phonetic contexts. Stimuli were 152 Japanese words containing /ɾ/ in all phonotactically possible contexts produced by two native Japanese speakers. Three stimulus randomizations were presented to 12 American English listeners for identification as ‘‘l,’’ ‘‘r,’’ ‘‘D’’ (=flap), ‘‘d,’’ ‘‘t,’’ ‘‘no sound,’’ or ‘‘other sound.’’ Results showed strong effects of syllable structure: Japanese /ɾ/ sounded more stoplike (‘‘D,’’ ‘‘d,’’ ‘‘t’’ responses) in consonantal contexts and more liquidlike (‘‘r,’’ ‘‘l’’ responses) in vocalic contexts. However, liquid responses were more likely to be ‘‘r’’ intervocalically, compared with ‘‘l’’ in initial position. Vowel quality also had a strong effect: Japanese /ɾ/ elicited more stop responses in high vowel ([i u]) contexts and more liquid responses in lower vowel ([a o]) contexts. Acoustic measures of the stimuli were generally consistent with the perceptual patterns. The perceptual and acoustic findings are compared with the results of recent training studies [Akayane-Yamada, Proc. 3rd Joint Meeting of ASA-ASJ, 953–958 (1996)] with Japanese listeners on English /ɹ–l/.