This study is aimed at verifying whether a language environment affects infants' ability to match the lip movements of vowel articulations with respective vocal sounds. Previous studies indicate that infants in English listening environment are able to match the lip movements of vowels /a/ and /i/ with respective vocal sounds. In this study, two sets of experiments consistently suggest that 8 month old Japanese infants can match the phonetic information of vowel /a/ to its respective visual information provided by visible lip articulation, while no evidence for one to one corresponding matching was found concerning vowel /i/. This unique result is possibly due to the language-specific visual and motor experience of vowel articulation pertaining to Japanese infants.
