Jacqueline Leybaert

The rhyming skills of deaf children educated with phonetically augmented speechreading

Two experiments investigated whether profoundly deaf childrens rhyming ability was determined by the linguistic input that they were exposed to in their early childhood. Children educated with Cued Speech (CS) were compared to other deaf children, educated orally or with sign language. In CS, speechreading is combined with manual cues that disambiguate it. The central hypothesis is that CS allows deaf children to develop accurate phonological representations, which, in turn, assist in the emergence of accurate rhyming abilities. Experiment 1 showed that the deaf children educated early with CS performed better at rhyme judgement than did other deaf children. The performance of early CS-users was not influenced by word spelling. Experiment 2 confirmed this result in a rhyme generation task. Taken together, results support the hypothesis that rhyming ability depends on early exposure to a linguistic input specifying all phonological contrasts, independently of the modality (visual or auditory) in which this input is perceived.

Spelling development in deaf and hearing children: Evidence for use of morpho-phonological regularities in French

This study investigated the processes that deaf school children use for spelling. Hearing and deaf spellers of two age groups spelled three types of words differing in orthographic transparency (Regular, Morphological and Opaque words). In all groups, words that could be spelled on the basis of phoneme-grapheme knowledge (Regular words) were easier than words that could be spelled only on the basis of lexical orthographic information (Opaque words). Words in which spelling can be derived from morphological information were easier than Opaque words for older deaf and hearing subjects but not for younger subjects. In deaf children, use of phoneme-grapheme knowledge seems to develop with age, but only in those individuals who had intelligible speech. The presence of systematic misspellings indicates that the hearing-impaired youngsters rely upon inaccurate speech representations they derived mainly form lip-reading. The findings thus suggest that deaf subjectss spelling is based on an exploitation of the linguistic regularities represented in the French alphabetic orthography, but that this exploitation is limited by the vagueness of their representations of oral language. These findings are discussed in the light of current developmental models of spelling acquisition.

Does math education modify the approximate number system? A comparison of schooled and unschooled adults

Does math education contribute to refine the phylogenetically inherited capacity to approximately process large numbers? The question was examined in Western adults with different levels of math education. Unschooled adults who never received math education were compared to unschooled-instructed adults who did not attend regular school but received math education in adulthood, and to schooled adults who attended regular school in childhood. In the number-comparison task (Exp. 1), the unschooled group was slower and made more errors than the other groups both when numerical symbols and nonsymbolic dot collections were presented. In the forced-choice mapping task (Exp. 2), the unschooled group experienced more difficulty than the others in linking large nonsymbolic and symbolic quantities, as well as in matching purely nonsymbolic quantities. These results suggest that Western adults who did not receive math education have less precise approximate number skills than adults who acquired exact number competences through math education.

Relationships between approximate number system acuity and early symbolic number abilities

Abstract The present study assessed the relationships between approximate and exact number abilities in children with little formal instruction to ask (1) whether individual differences in acuity of the approximate system are related to basic abilities with symbolic numbers; and (2) whether the link between non-symbolic and symbolic number performance changes over the development. To address these questions, four different age groups of 3- to 6-year-old children were asked to compare pairs of train wagons varying on numerical ratio, as well as to complete exact tasks including number words or Arabic numbers. When correlation analyses were conducted across age groups, results indicated that performance in numerosity comparison was associated with mastery of symbolic numbers, even when short-term memory, IQ and age were controlled for. Separate analyses by age group revealed that the precision in numerosity discrimination was related to both number word and Arabic number knowledge but differently across the development.

Methods to Establish Subtypes of Developmental Dyslexia

Do the developmental dyslexics form a homogeneous population, with a unique underlying impairment, or do they form distinct subgroups, thus opening up the possibility for different sources of impairment? In this chapter we compare different methods to subgroup dyslexic children and discuss the methodological implications.

Symbolic Number Abilities Predict Later Approximate Number System Acuity in Preschool Children

An ongoing debate in research on numerical cognition concerns the extent to which the approximate number system and symbolic number knowledge influence each other during development. The current study aims at establishing the direction of the developmental association between these two kinds of abilities at an early age. Fifty-seven children of 3–4 years performed two assessments at 7 months interval. In each assessment, childrens precision in discriminating numerosities as well as their capacity to manipulate number words and Arabic digits was measured. By comparing relationships between pairs of measures across the two time points, we were able to assess the predictive direction of the link. Our data indicate that both cardinality proficiency and symbolic number knowledge predict later accuracy in numerosity comparison whereas the reverse links are not significant. The present findings are the first to provide longitudinal evidence that the early acquisition of symbolic numbers is an important precursor in the developmental refinement of the approximate number representation system.

Phonological Development in Relation to Native Language and Literacy: Variations on a Theme in Six Alphabetic Orthographies.

Phonological development was assessed in six alphabetic orthographies (English, French, Greek, Icelandic, Portuguese and Spanish) at the beginning and end of the first year of reading instruction. The aim was to explore contrasting theoretical views regarding: the question of the availability of phonology at the outset of learning to read (Study 1); the influence of orthographic depth on the pace of phonological development during the transition to literacy (Study 2); and the impact of literacy instruction (Study 3). Results from 242 children did not reveal a consistent sequence of development as performance varied according to task demands and language. Phonics instruction appeared more influential than orthographic depth in the emergence of an early meta-phonological capacity to manipulate phonemes, and preliminary indications were that cross-linguistic variation was associated with speech rhythm more than factors such as syllable complexity. The implications of the outcome for current models of phonological development are discussed.

Neurolinguistic development in deaf children: the effect of early language experience

Recent investigations have indicated a relationship between the development of cerebral lateralization for processing language and the level of development of linguistic skills in hearing children. The research on cerebral lateralization for language processing in deaf persons is compatible with this view. We have argued that the absence of appropriate input during a critical time window creates a risk for deaf children that the initial bias for left-hemisphere specialization will be distorted or disappear. Two experiments were conducted to test this hypothesis. The results of these investigations showed that children educated early and intensively with cued speech or with sign language display more evidence of left-hemisphere specialization for the processing of their native language than do those who have been exposed later and less intensively to those languages.

Reading and spelling acquisition in two different teaching methods: A test of the independence hypothesis

The development of word reading and word spelling was examined in French speaking children initially instructed either by a phonic or a whole-word method. Second, fourth and sixth graders were administered to reading and spelling tests in which grapho-phonological regularity, frequency, length and lexicality were manipulated. The results showed that in both curricula, reading and spelling acquisition can be characterized by a parallel increase in the use of sub-lexical correspondences and in the reliance on word-specific information. Contrary to a simple view of lexical development according to which the use of analytical knowledge and the use of word-specific knowledge correspond to two different cognitive processes that develop independently from each other, whole-word children did not appear to rely more on whole-word knowledge. On the contrary, and paradoxically, grade 2 whole-word children tended to use analytical correspondences to a greater extent than their peers. In later development, reading matched phonic and whole-word groups did not differ from each other. It is argued that the results support the hypothesis that the acquisition of sub-lexical correspondences constitutes a necessary step in the acquisition of reading and spelling. We conclude that the analytic comparison of different curricula provides a naturalistic tool for the study of the dynamics of development.

PHONOLOGICAL REPRESENTATIONS IN DEAF CHILDREN : THE IMPORTANCE OF EARLY LINGUISTIC EXPERIENCE

It is argued that the development of phonological representations in deaf children does not necessarily depend on auditory speech experience, neither at the perception nor at the production level. Instead, this development depends upon early experience of an input in which all phonological contrasts are well specified, independently of input modality. This is argued on the basis of the studies investigating phonological and morpho-phonological abilities of profoundly deaf children early exposed to Cued Speech. The paper is concluded with some speculations about the effect of early exposure to CS on the development of language specific processes housed in the left-hemisphere.