Acquisition of L2 Length Contrasts

A question that currently receives much attention in the study of the acquisition of second language (L2) phonology is: can new phonological structure be acquired? By phonological structure, we are referring not only to segments and syllables, but also stress and tone. Recent work by Brown (2000) on the acquisition of segmental phonology suggests that L2 learners are not merely struggling with L2 phonemes that are absent in their first language (L1), rather it is the novel features of the L2 that are presenting the learners with difficulty: the features present in the L1 grammar of the learner influence the perception and acquisition of L2 phonology. An examination of the acquisition of the English /l/ vs. /r/ distinction by Chinese and Japanese speakers revealed that the Chinese speakers were able to acquire the English contrast while the Japanese speakers were not, in spite of the fact that both Chinese and Japanese lack /l/ and /r/. Brown (2000) assumes that the feature [CORONAL] allows the distinction between the two liquids in English, and argues that the reason for the difference between the two groups of learners can be traced down to differences in the features present in each L1: the Chinese speakers had the feature [CORONAL] elsewhere in their L1 inventory and thus were able to properly construct the representations required to distinguish /l/ and /r/. The Japanese speakers, on the other hand, lacked the feature [CORONAL] in their L1 inventory and thus were unable to represent the novel contrast, resulting in an inability to distinguish between the two phonemes. Furthermore, Matthews (1997) demonstrates that training on the /l/ vs. /r/ contrast does not result in improved perception. It seems, then, that if the relevant feature required to construct the phonological representation for a novel phoneme is present in the learner’s L1, s/he will be able to re-deploy it and successfully acquire the new L2 contrast. If the required feature is absent, however, the contrast cannot be acquired: that is, new phonological structure cannot be triggered in L2 acquisition. While current work (Archibald in progress) is examining Brown’s (2000) conclusions in a broader perspective by examining acquisition of segmental structure, syllable structure, and tone by L2 learners, here we report on a case study focusing on the acquisition of Japanese vowel and consonant length contrasts by a native speaker of English. Japanese maintains length contrasts in both the consonantal (/t/ vs. /tt/) and vocalic (/a/ vs. /a:/) inventories (Han 1994, 1962; Homma 1981, 1973). English, on the other hand, contrasts monomoraic and bimoraic vowels, a contrast that approximates the Japanese vowel length distinction with an added complication of vowel quality differences, but crucially English does not distinguish between long and short consonants. The question, then, is: can English speakers acquire length contrasts in a second language? Two possibilities present themselves in answer to this question. The first predicts that native speakers of English will be unable to acquire Japanese geminate and single consonant contrasts due to the fact that English does not contrast consonant length. These same speakers would, however, successfully acquire Japanese vowel length contrasts, since English has monomoraic and bimoraic vowels, thus the feature for vowel length is present in the L1 grammar. The second possibility predicts that native speakers of English will be able to acquire the length contrasts found in Japanese for both consonants and vowels owing to the fact that their L1 maintains a length contrast. Previous work by Han (1992) provides empirical evidence of native English speakers’ difficulty in dealing with geminate and single stop contrasts in Japanese, noting that these speakers often fail to produce the appropriate contrasts, and that when they succeed in doing so, the timing of the geminate stop closure differs significantly from that of a native speaker. Han’s (1992) results are summarized in Tables 1 and 2 below. It is useful to note that due to individual differences among speakers for rate of