Syllable Structure Complexity Research Articles

LEARNING DIRECTION MATTERS

AbstractThis study examines the acquisition process of speech rhythm in Dutch learners of Spanish (DLS) and Spanish learners of Dutch (SLD) at different proficiency levels to determine whether learning direction affects the success of rhythm acquisition in a foreign language (L2). Analyses of lengthening effects showed that the two learner groups followed different developmental paths in their acquisition of accentual and final lengthening: Both groups showed transfer effects from the L1, but while the DLS systematically approached their target until attainment, the SLD showed more variability in their development. In addition, syllable structure complexity affected L2 rhythm acquisition, and to a substantially larger extent for the SLD compared to the DLS. The results support a model of L2 rhythm acquisition in which learning direction is included as a factor, and that allows for the interaction of various language-specific properties that contribute to speech rhythm, like syllable structure complexity.

Word length is (in part) predicted by phoneme inventory size and syllable structure

Based on anecdotal data from a few languages, it has been proposed that typical word length in a language is correlated with the size of the phoneme inventory: more phonemes predicts shorter words. This hypothesis has now been examined in some detail using a substantial sample of languages. A standardized text widely employed for phonetic illustrations is used, namely, the fable of “The North Wind and the Sun.” Illustrations published by the IPA and others have been collected for over 100 languages. These illustrations are arguably well-matched in style and vocabulary and reflect natural inflected forms embedded in text. Average word-length in these texts is calculated and correlated with the size of the language’s consonant and vowel inventories, as well as an index reflecting the permitted complexity of syllable structure. Vowel inventory is treated in two ways; basic vowels (just the distinctions on the basic height, backness and rounding parameters), and total vowels (including other distinctions such as nasalization, length, and voice quality). Mean word length is indeed negatively correlated with size of consonant and vowel inventories, most strongly with the number of basic vowels. More complex syllable structures also correlate with a shorter mean word length.

Speech rhythm of monolingual and bilingual children at age 2;6: Cantonese and English

Previous studies have showed that at age 3;0, monolingual children acquiring rhythmically different languages display distinct rhythmic patterns while the speech rhythm patterns of the languages of bilingual children are more similar. It is unclear whether the same observations can be found for younger children, at 2;6. This study compared five Cantonese–English simultaneous bilingual children with five monolingual children in each language using both rhythmic metrics and qualitative data on syllable structure complexity and lexical stress. Results show that while the speech rhythms of monolingual children are different at 2;6, the rhythmic patterns of bilingual children are less distinct.

Assessing the treatment effects in apraxia of speech: introduction and evaluation of the Modified Diadochokinesis Test

The number of reliable and valid instruments to measure the effects of therapy in apraxia of speech (AoS) is limited. To evaluate the newly developed Modified Diadochokinesis Test (MDT), which is a task to assess the effects of rate and rhythm therapies for AoS in a multiple baseline across behaviours design. The consistency, accuracy and fluency of speech of 24 adults with AoS and 12 unaffected speakers matched for age, gender and educational level were assessed using the MDT. The reliability and validity of the instrument were considered and outcomes compared with those obtained with existing tests. The results revealed that MDT had a strong internal consistency. Scores were influenced by syllable structure complexity, while distinctive features of articulation had no measurable effect. The test-retest and intra- and inter-rater reliabilities were shown to be adequate, and the discriminant validity was good. For convergent validity different outcomes were found: apart from one correlation, the scores on tests assessing functional communication and AoS correlated significantly with the MDT outcome measures. The spontaneous speech phonology measure of the Aachen Aphasia Test (AAT) correlated significantly with the MDT outcome measures, but no correlations were found for the repetition subtest and the spontaneous speech articulation/prosody measure of the AAT. The study shows that the MDT has adequate psychometric properties, implying that it can be used to measure changes in speech motor control during treatment for apraxia of speech. The results demonstrate the validity and utility of the instrument as a supplement to speech tasks in assessing speech improvement aimed at the level of planning and programming of speech.

The usefulness of metrics in the quantification of speech rhythm

The performance of the rhythm metrics ΔC, %V, PVIs and Varcos, said to quantify rhythm class distinctions, was tested using English, German, Greek, Italian, Korean and Spanish. Eight participants per language produced speech using three elicitation methods, spontaneous speech, story reading and reading a set of sentences divided into “uncontrolled” sentences from original works of each language, and sentences devised to maximize or minimize syllable structure complexity (“stress-timed” and “syllable-timed” sets respectively). Rhythm classifications based on pooled data were inconsistent across metrics, while cross-linguistic differences in scores were often statistically non-significant even for comparisons between prototypical languages like English and Spanish. Metrics showed substantial inter-speaker variation and proved very sensitive to elicitation method and syllable complexity, so that the size of both effects was large and often comparable to that of language. These results suggest that any cross-linguistic differences captured by metrics are not robust; metric scores range substantially within a language and are readily affected by a variety of methodological decisions, making cross-linguistic comparisons and rhythmic classifications based on metrics unsafe at best.

The acquisition of speech rhythm by three-year-old bilingual and monolingual children: Cantonese and English

This study investigates the acquisition of speech rhythm by Cantonese–English bilingual children and their age-matched monolingual peers. Languages can be classified in terms of rhythmic characteristics that define English as stress-timed and Cantonese as syllable-timed. Few studies have examined the concurrent acquisition of rhythmically different languages in bilingual children. This study uses data of six Cantonese–English bilingual children around age 3;0 and compares them with six monolingual children in each language using recently developed acoustic rhythmic metrics on consonantal, vocalic and syllabic intervals. Qualitative data on syllable structure complexity and vowel quality are also included. Results on syllable duration show that monolingual children display distinct rhythmic patterns while the differences between the two languages of the bilingual children are less distinct. Bilingual English has less durational variability than monolingual English. Bilingual children have a distinct phonological developmental trajectory from monolingual children, which is manifested in acquisition delay and is influenced by language dominance. This shows that the two phonologies interact at the prosodic level.

Investigating the effects of syllable complexity in Russian-speaking children with SLI

This study examined the effect of number of syllables and syllable structure on repetition of pseudo-words by Russian-speaking children with Specific Language Impairment (SLI) and typically developing (TD) children. One hundred and forty-four pseudo-words, varying in length and syllable complexity, were presented to two groups of children: 15 children with SLI, age range 4 ; 0 to 8 ; 8, and 15 TD children matched in age to the SLI group. The number of errors in the repetition of pseudo-words was analyzed in terms of the number of syllables and syllable complexity. The results demonstrated that children with SLI have deficits in working memory capacity. In addition to the pseudo-word length, the repetition performance was affected by syllable structure complexity.

Are phonological processes the same or different in low literacy adults and children with or without reading disabilities?

The primary purpose of the study reported here was to examine whether phonological processes are the same or different in low literacy adults and children with or without reading disabilities in a consistent orthography. A sample of 150 subjects was selected and organized into four different groups: 53 low literacy adults, 29 reading disabled children, 27 younger normal readers at the same reading level as those with reading disabilities and low literacy adults, and 41 normal readers matched in age with the reading disabled group. We administered phonological awareness tasks which included items with different complexity of syllable structure. The results showed that the complexity of syllable structure had not a particularly marked effect on low literacy adults. Rather, the deletion task revealed the phonological deficit in low literacy adults across all syllable structures.

Rhythm in English clear speech

This study investigates the effect of hyperarticulated, intelligibility-enhancing clear speech on English speech rhythm. Ramus et al. [Ramus et al., ‘‘Correlates of linguistic rhythm in the speech signal,’’ Cognition 72, 265–292 (1999)] showed that temporal properties of a speech signal such as the percentage of vocalic intervals (%V) and variability of consonantal and vocalic intervals (C, V) can be related to phonological properties such as presence/absence of unstressed vowel reduction and syllable structure complexity, and are consequently quite successful at grouping languages into the traditional rhythmic classes (stress-, syllable-, and mora-timed). Here, we explore whether/how clear speech affects stress-timed characteristics of English sentences in terms of these measures. Results revealed that the proportion of vocalic intervals (%V) within sentences remained stable across speaking styles, i.e., consonants and vowels were lengthened equally in clear speech. However, variability of both vocalic and consonantal intervals (V, C) was higher in clear than in conversational speech. The increase in V and C was achieved primarily through insertion/strengthening of short vocalic and consonantal segments that were dropped or coarticulated with surrounding sounds in conversational speech, making word and syllable boundaries more salient. These results suggest that increased intelligibility of clear speech can in part be attributed to prosodic structure enhancement by means of enhanced syllable and word boundaries demarcation.

Is the deficit in phonological awareness better explained in terms of task differences or effects of syllable structure?

The primary purpose of the study reported here was to explore the effects of the complexity of syllable structure and the effects of task differences in the explanation of deficit in phonological awareness (PA). A sample of 97 subjects was selected and organized into three different groups: 29 reading-disabled (RD) children, 41 normal readers matched in age with the former, and 27 younger normal readers at the same reading level as those with reading disabilities. We administered PA tasks which included items with different complexity of syllable structure. The results showed that the complexity of syllable structure had no particularly marked effect on the dyslexic children. Rather, the isolation task revealed the phonological deficit across all syllable structures.

Defining Phonological Awareness and Its Relationship to Reading Skills in Low-Literacy Adults.

The main purpose of the study reported here was to investigate the relative importance of complexity of syllable structure and task differences in measuring phonological awareness in low-literacy adults. This study is a replication of a study with children conducted by S. A. Stahl and B. A. Murray (1994). Results indicated that the complexity of syllable structure did indeed better describe the construct of phonological awareness in low-literacy adults. At the same time, the authors also found some differences in the pattern of literacy acquisition for their Spanish adults in comparison with child literacy acquisition in English.