THE EFFECT OF ORTHOGRAPHIC KNOWLEDGE ON SYLLABLE SEGMENTATION : A CROSS-LINGUISTIC STUDY

Recent psycholinguistic research has revealed a variety of significant intrasyllabic units, illustrating how segments can cohere into higher-order constituents within a syllable. Among these are the rime (for English and perhaps also Chinese), the body (for Korean), and the mora (for Japanese). However, the native speakers tested so far in all four of the language groups mentioned were all well educated, literate, and often even bilingual. Thus they were all exposed to the writing systems of their own and/or their second language, which (for different reasons in each case) might have predisposed them to perform the way they did. In the present research we are testing speakers of these languages who have not been subjected to the influence of L1 spelling. Results to date show no differences between literate and preliterate Korean children, while research continues with other nonliterate speakers and the other languages. 1. PRIOR RESEARCH The research outlined here is part of a larger cross-linguistic investigation of phonological units in languages of diverse types. Previous research has focused on the status of the syllable (e.g., CVC) and a variety of its hypothesized intrasyllabic constituents, including the segment (C or V), the rime (VC), the body (CV), and the mora (a timing unit that can have several phonetic manifestations, including CV). A variety of diverse experimental tasks has been employed in this effort, including (1) word blending, (2) global sound similarity judgments (SSJs), and (3) concept formation. Using a forced-choice version of the word blending task, for example, it was found that English speakers preferred onset plus rime word blends, with break points before the vowel (e.g., SIEVE + FUZZ > SUZZ), while Korean speakers preferred body plus coda blends, breaking after the vowel (e.g., KANG + SEM > KAM) [1, 2]. In addition, a linear regression analysis of SSJ ratings for CVC-CVC pairs revealed that shared individual segments (Cs or V) and a shared rime (CV) unit all made significant independent contributions to mean similarity scores from English speakers, while it was the body (CV) unit that complemented the segments in the results of a comparable task by Korean speakers; moreover, for CVC pairs sharing two segments out of three, those which shared a final VC were judged to be significantly more similar by English speakers than pairs which shared a common initial CV, whereas the opposite was true for Korean speakers [3, 4]. Furthermore, in a concept formation study (not done in English), Korean speakers found that a target set of words all sharing the common body element /ka/ was easier to master than a target set of words all sharing the common rime element /ak/ [5]. Taken together, these results suggest that English and Korean CVC syllables may be segmented differently, with onset (C) + rime (VC) constituents manifested in English, but body (CV) + coda (C) units in Korean. Other studies have likewise confirmed the possibility of a mora unit in Japanese [6, 7], while the results for Chinese have been mixed, depending on the nature of the task employed. This suggests that a more complicated interplay of factors may be at work in that language family [8]. 2. THE INFLUENCE OF ORTHOGRAPHY Apart from the Chinese case, however, the results of these prior studies are rather remarkably consistent, especially in view of the diversity of experimental tasks that have been utilized, each of which is very different in terms of the kind of responses they call for and/or the levels of metalinguistic awareness that they presumably invoke. In word blending, for example, subjects produce novel blends (or, in a forced-choice version of the task, choose between one blend and another), a task which would seem to overtly direct their attention to intrasyllabic break points, and not necessarily to the whole units that are defined by these breaks. In the concept formation task, however, subjects are directed to overtly discover the phonological units that all members of the target set share, guided by feedback as to which stimuli belong to the target set and which do not. In the SSJ task, by contrast, subjects are not required to attend to either break points or constituent elements at all, but merely to make global intuitive assessments of the overall similarity in sound of each of the syllable pairs presented. The fact that all three tasks can lead to the same conclusions (as in the Korean case) shows, at the very least, that the findings are not the result of a strategy that is linked to any specific task. For all of this, at least one major problem remains which makes the interpretation of the results of these studies difficult. Specifically, all of the subjects tested in the research described above have been literate adults, and mostly highly educated university students, as well, and hence well versed in the orthographic norms of the languages in which they were tested. The factor of orthographic knowledge has therefore not been controlled in any of the studies reported. What kind of biases might knowledge of the writing systems of the languages tested be reasonably expected to introduce? As numerous investigators of child language have pointed out, since standard English spelling contains units (letters and digraphs) that largely represent individual phonemic segments, the writing system provides a major (and perhaps decisive) impetus for the identification of these segments; thus, some argue, it is more than mere coincidence that phonemic awareness arises in Englishspeaking children at just about the same time that they are learning to read [9, 10, 11] (see also [12], which demonstrates deficiencies in segment manipulation skills by Chinese speakers who, though literate in Chinese characters, have not been exposed to either English or any other segment-based transliteration system, such as pinyin.) On the other hand, though awareness of the segment may well be implicated in exposure to a segment-based alphabetic writing system, we have no hard evidence that any larger phonological units are, such as the syllable or the rime. Thus, page 93 ICPhS99 San Francisco while it is true that English letters can sometimes represent strings that are larger than a single segment (witness the letter X, which often represents the sequence /ks/, as in the word MIX, or even a whole syllable, as in X-RAY), such examples are atypical and uncharacteristic of the writing system as a whole. Despite its widespread use of digraphs and its many familiar irregularities and inconsistencies (and even logographic tendencies), this system still utilizes an alphabet that remains strongly attuned to the ÒphonographicÓ tradition of its Graeco-Roman precursors, which is to match individual letters with individual C and V sounds [13]. In sharp contrast, however, the standard Korean orthography contains not only symbols for individual segments but also consistently bundles these elements into syllable-like packages, by stacking the letters in vertical arrays. Moreover, in CVC syllables where the vowel letter is itself written with a vertical orientation, the first two letters (representing CV) are written on the same (top) line, with the letter for the coda consonant written below it. This orthographic convention thus strongly suggests that vowels are more closely associated with preceding consonants than with following ones, introducing a potential bias in favor of a body or CV constituent. In the case of Japanese, where the mora is the unit of primary experimental interest, the case for potential orthographic influence is even stronger, as both of the so-called ÒsyllabariesÓ of Japanese actually consist of symbols that represent individual mora units, rather than either syllables or segments. Thus, for words written in either of these kana, a mora count consistently matches the number of letters used to spell it [14]. Finally, in the case of Chinese, the standard orthography, of course, utilizes ideographic (or logographic) characters, each of which is coextensive with both a single morpheme and a single syllable. This might naturally be expected to introduce a bias in favor of the syllable, but not towards any particular phonological units smaller than this. The complication introduced in the Chinese research, however, has not arisen through the standard orthography, but through a secondary writing system that is widely employed in Taiwan, where most of the prior research on segmentation was carried out. This system, called chuyin-fuhao (or bopomofo, informally), is used for schoolwork in Mandarin during the early school years, while the children are still struggling with the Chinese characters, and it contains symbols which represent individual ÒinitialÓ (onset) and ÒfinalÓ (rime) units. The potential bias so introduced in favor of an onset-rime analysis for Mandarin is obvious, and we cannot discount the possibility that this same bias might also be extended to spoken Taiwanese, given the typological similarities of Mandarin and Taiwanese and the fact that all Taiwanese speakers are required to learn Mandarin in school. In sum, therefore, we can see that (with the possible exception of the rime unit in English), there is potential orthographic contamination with respect to all of the units and the languages focused upon in the line of research involved here. To ensure that this bias was not responsible for the results obtained in the earlier experiments with literate, adult subjects, therefore, we are expanding our tests to include subjects who do not know how to read or write the languages involved and who would thus not be subject to the particular biases that each orthographic convention might introduce. 3. TESTING PRELITERATE CHILDREN Our long-term plans include the testing of three different types of nonliterate speakers, including both illiterate adults and splitliterate bilinguals (such as emigrants to North America who hav