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Language acquisition Language learing Language in deaf children with a cochlear implant

Multilingual self speech audiometry (MuLiSSA). 01/04/2023 - 31/03/2025

Abstract

Disabling hearing loss (DHL) is one of the most prevalent public health issues. WHO estimates that by 2050 one out of every ten people (700 million) will be affected by DHL, putting enormous pressure on global health care systems. Speech audiometry is the core clinical test to diagnose and treat DHL. Currently, speech audiometry can only be performed in a sound booth in the presence of the qualified clinician, an audiologist, to perform the scoring. The condition for correct scoring is that the audiologist is able to understand the language of the speech test material. This project aims at taking speech audiometry out of the booth, into the waiting room and the home environment, at least for people using a modern hearing device with wireless audiostreaming capability. Solution for the multi-language setting is the other important goal of this project. A first project objective is to build remote speech testing capability and demonstrate its feasibility at TRL6 level. The "boothless testing" demonstrator will cover existing speech testing materials in multiple languages. The technology blocks relating to self-testing need to be matured from TRL3 onwards. A closed set testing user interface will be compared to open set testing. Furthermore, the effects of the wireless link technology limitations will be fully characterized in terms of their impact of speech testing outcomes. The frequency and impact of cognitive distractions and background sounds will be considered as well, especially for the home environment. Criteria for the TRL6 self-testing toll gate are good test-retest reliability and correspondence to in-booth testing (r > 0.9). A second objective is to extract more information out of speech audiometry tests. Current tests only provide an average recognition score. We want to introduce more precision, measuring as well which phoneme errors an individual patient is making. This requires the alteration of speech testing materials. Currently test lists are too short and do not cover adequately the phonemes of the language. To develop the concept, the project will start from first principles, theoretical phonetic studies and existing clinical data. As part of the objective the project will explore how clinicians can use this information for optimize device fitting or hearing rehabilitation. We will first pilot this approach in Dutch. Goal is to reach a proof-of-concept (TRL3) maturity. The third objective is to investigate the feasibility of rolling out the precision audiometry concept in many languages. Current speech tests lack comparability across languages, which hampers consolidation of hearing outcomes across multiple language areas. The current speech audiometry test approach requires the clinicians to master the language as they have to score manually the responses given by the patient on the played audiomaterial. The lack of comparability and the requirement for the clinician to master the speech test language are blockers for testing individual patients in their native language.

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  • Research Project

How to make intelligibility measurements intelligible? A methodological study extending the framework of comparative judgement. 01/10/2021 - 30/09/2025

Abstract

Suppose a speech therapist or a teacher is asked to estimate the intelligibility of a young child's speech. Speech intelligibility is an intuitively appealing but also a difficult notion to define formally. So how can it be measured reliably, validly, and efficiently? Traditionally, both holistic (e.g., assigning a numerical appreciation) and analytical (e.g., assessing against a set of criteria) methods have been used for assessment. However, research shows that the different methods have their pitfalls and shortcomings. A method that has recently been propagated mainly from the angle of educational assessment is comparative assessment. At the basis of this method are insights from psychology that show that people are better able to compare objects than to assign a score to them one by one on a certain characteristic. A speech therapist then assesses two speech languages, for example, and determines which of the two is most intelligible. Such judgments appear to be more reliable than assigning a holistic score. The goal of this project is twofold. First, we want to investigate the generalizability of comparative judging and its mérites in the domain of speech research. Then, we want to extend the method itself and develop an appropriate statistical model. 1. Generalization: the method of pairwise comparison is especially emerging in the broad domain of measuring competencies in the educational context. In this project, we want to closely examine the generalizability of comparative assessment to other domains in which people assess, especially in the domain of the scientific study of speech. More specifically, we ask the question: does comparative assessment lead to reliable, valid and efficient assessments of the intelligibility of young children's speech? 2. Extension: the current form of comparative assessment is limited to a simple pairwise comparison, i.e. dichotomous choosing between two alternatives. The reason is that the statistical model used to model the data, the Bradley-Terry-Luce model, only allows for dichotomous data. However, pairwise comparison can be extended to ordinal and scale-based ways of selection and, in addition, it may be important to take a multidimensional approach to assessment (comparing on multiple underlying aspects of intelligibility). In this study, we extend the statistical model into a generic model that helps to analyze different forms of data.

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  • Research Project

The development of fundamental frequency in babbles and early words of typically developing children and children with hearing impairment: the case of intrinsic vowel pitch. 01/01/2021 - 31/12/2024

Abstract

In all languages of the world high vowels (such as /i/ in 'key') and /u/ in 'who') are pronounced with a higher pitch than low vowels (such as /a/ in 'far'). This phenomenon is known as 'intrinsic vowel pitch'. In the past, this phenomenon has been explained in two ways. On the one hand, intrinsic vowel pitch has to do with the operation of the speech organs: during the articulation of /i/ and /u/ the tongue is lifted far forward in the mouth. This tension pulls on the larynx and this stretches the vocal folds so that a higher pitch is obtained. In vowels like /a/ the vocal folds are not stretched to the same degree so that a lower tone is heard. On the other hand, this phenomenon supports the intentions of speakers who aim to make vowels sound as different as possible from each other in order to speak clearly. Scientists do not agree on which explanation is correct, but they do agree on the following: if the first explanation is correct then intrinsic vowel pitch is expected to occur in babble of deaf babies. Remarkably, this has never been systematically investigated in a large-scale study and this is precisely what this project aims to investigate.

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  • Research Project

FWO Sabbatical 2019-2020 (Steven Gillis). 01/10/2019 - 30/09/2020

Abstract

The aims of planned research are: 1. Study of the speech and language development in congenitally deaf children with a cochlear implant: preparation of a state-of-the-art of the recent literature including our own empirical findings; 2. Study of speech and language development in congenitally deaf children with an auditory brainstem implant: analysis of a recently collected longitudinal corpus; 3. Preparation of the longitudinal and cross-sectional corpora collected by our research group over the last 40 years: integration into TalkBank.

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  • Research Project

A longitudinal approach to phonetic enhancement in infant directed speech: normally hearing infants and hearing-impaired infants with a cochlear implant. 01/01/2018 - 31/12/2021

Abstract

The aim of the present project is to investigate Infant Directed Speech (IDS). Since the pathbreaking work of i.a. Snow & Ferguson (1977) a consensus has grown that IDS exhibits particular characteristics that distinguish it from Adult Directed Speech (ADS). A case in point is the production of vowels: in IDS vowels are produced more "clearly" than in ADS, as can be inferred from the larger vowel space in IDS (Kuhl 2000). This "received wisdom" has recently been fundamentally questioned. For instance, Martin et al. (2015) conclude their study of Japanese IDS and ADS: "Mothers speak less clearly to infants than to adults." We want to further investigate this contradiction by replicating the findings reported in the literature using a large database of Dutch IDS and ADS, and by systematically scrutinizing two variables that have been largely neglected up till now: 1. longitudinal development: how does IDS change relative to chronological age and, more importantly, "linguistic age" as represented by a.o. the child's evolving cumulative vocabulary and utterance length? 2. characteristics of the child as interlocutor: does speech directed to a child with normal hearing (NH) differ from speech directed to a deaf child with a cochlear implant (CI)?

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  • Research Project

Artificial Hearing: Neural Networks and the Acoustic Identifiability of Children with Cochlear Implants. 01/10/2017 - 30/09/2021

Abstract

Approximately 1 of out of 1,000 neonates is diagnosed with a bilateral severe-to-profound hearing loss. Hearing aids, such as cochlear implants (CI), have opened up unprecedented perspectives for these children. Although CIs generally lead to remarkable gains in the spoken language proficiency of hearing-impaired children, their speech remains deviant from normal hearing children's speech, even after several years of device use. Adult speakers are able to discriminate between the speech of CI-children and that of normally hearing children. In other words, CI children's speech remains identifiable as the speech of a hearing impaired individual. Surprisingly, the exact characteristics on which adults base such decisions have so far remained elusive, which makes it difficult for clinicians to finetune speech rehabilitation programs. In this project, we aim to exploit recent advances in "Deep" Representation Learning to close in on these characteristics. Recent connectionist models (neural networks) have shown a promising performance in modelling raw audio signals, such as recorded speech. Through the careful inspection, visualization and interpretation of such models, we aim to uncover which specific features in the speech of cochlear-implanted children are responsible for the identifiability of their speech production.

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  • Research Project

Auditory brainstem implantation and language development 01/10/2017 - 30/09/2020

Abstract

This project aims to investigate the oral language development of congenitally hearing-impaired children with an auditory brainstem implant (ABI). ABI is a relatively new development to restore the hearing of children with a severe-to-profound hearing loss due to i.a. the absence of the auditory nerve. The speech perception outcomes of children with ABI have been investigated, but detailed linguistically underpinned studies of their speech production are virtually lacking. The goal of the present research project is to provide a first linguistically motivated description of the lexical and phonological development of children with ABI. Their development will be evaluated against the background of the acquisition process of normally hearing children and that of severe-to-profound hearing-impaired children who received a cochlear implant. The focus is on the longitudinal development of the word productions of children with ABI. First, we investigate their cumulative vocabularies and the balance between their spoken and signed words (lexical development). Second, their word productions are analysed from a phonological perspective: in what order are segments acquired and what phonological regularities account for that order and (possible) deviations from that order? Which segmental substitution and deletion patterns occur? What is the consistency and variability of their productions and how does the accuracy of their word productions develop relative to the adult target forms?

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  • Research Project

Identifiability and intelligibility of the speech of hearing impaired children using a cochlear implant 01/10/2017 - 30/09/2019

Abstract

Until recently children who were born "deaf" remained "deaf", and thus were unable to acquire spoken language. Fortunately nowadays deaf children with a cochlear deficit can be helped with a surgical intervention: they receive a cochlear implant (CI) very early in life so that they can "hear", i.e., can experience sound sensations. The first concern that the parents of these children phrase, is: "will my child hear with an implant?" The answer is definitely positive. The second question usually is: "will my child speak and sound like a normal hearing (NH) child of the same age?" This question remains unanswered. We want to address this issue from two perspectives: the identifiability and intelligibility of CI children. Recent findings indicate that the speech of 6- to 7-year-old CI users deviates from that of NH peers in particular fine details. But are those details that we can measure also detectable by the human ear? Are they sufficient to reliably identify CI children's speech? This will be investigated by having people listen to recordings of speech of CI children, children with an acoustic hearing aid (HA), and NH children. A second main research question concerns the intelligibility of CI children's speech. When the children enter mainstream primary school, it is quintessential to know if they are intelligible for people not familiar with them. In this project we will assess their intelligibility using different methodologies.

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  • Research Project

An acoustic analysis of lexical stress and rhythm in early speech interactions of Dutch children and their primary caretakers: A longitudinal study. 01/10/2015 - 30/09/2018

Abstract

The main objective of this study is to investigate the acquisition of "lexical" stress and rhythm in the period when children produce canonical babbling and their first identifiable words. A good understanding of these phenomena in children's speech is of prime importance because it has been shown that prosody plays a cardinal role in children's language acquisition.

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  • Research Project

Identifiability and intelligibility of the speech of hearing impaired children using a cochlear implant. 01/10/2015 - 30/09/2017

Abstract

Until recently children who were born "deaf" remained "deaf", and thus were unable to acquire spoken language. Fortunately nowadays deaf children with a cochlear deficit can be helped with a surgical intervention: they receive a cochlear implant (CI) very early in life so that they can "hear", i.e., can experience sound sensations. The first concern that the parents of these children phrase, is: "will my child hear with an implant?" The answer is definitely positive. The second question usually is: "will my child speak and sound like a normal hearing (NH) child of the same age?" This question remains unanswered. We want to address this issue from two perspectives: the identifiability and intelligibility of CI children. (1) Identifiability: Recent findings indicate that the speech of 6- to 7-year-old CI users deviates from that of NH peers in particular fine details. But are those details that we can measure also detectable by the human ear? Are they sufficient to reliably identify CI children's speech? This will be investigated by having people listen to recordings of speech of CI children, children with an acoustic hearing aid (HA), and NH children. (2) Intelligibility: A second main research question concerns the intelligibility of CI children's speech. When the children enter mainstream primary school, it is quintessential to know if they are intelligible for people not familiar with them. In this project we will assess their intelligibility using different methodologies.

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  • Research Project

Bootstrapping operations in language acquisition: a computational psycholinguistic approach. 01/01/2014 - 31/12/2017

Abstract

The acquisition of abstract linguistic categories is investigated. Computational models of bootstrapping operations are constructed in order to investigate how knowledge from one domain can be instrumental in acquiring knowledge of another domain. In our simulations the language addressed to very young children is used in an attempt to elucidate how grammatical categories and grammatical gender are acquired given a combination of distributional, phonological and morphological bootstrapping.

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  • Research Project

Stress and Rhythm in Early Speech Productions of Hearing and Congenitally Deaf Children with a Cochlear Implant: A Longitudinal Study. 01/11/2013 - 31/10/2017

Abstract

Newborn babies have been shown to be sensitive to the speech melody of the language that they hear: they recognise the word stress patterns of their mother's language, and they are sensitive to the rhythm of that language (for instance, babies can distinguish what has been called the 'Morse Code' rhythm of Germanic languages and the 'Machine Gun' rhythm of Romance languages). Thus, already in the first year of life, infants seem to know a lot about how their ambient language sounds. Nevertheless, it is not known when and how they use this knowledge in their own speech production. This project investigates infants' babbling (adult sounding syllable sequences) and their early word productions in the first two years of life. The main research question is: when and how do they produce stress (the relative prominence of syllables) and when do we find evidence that they adopt the speech rhythm of the ambient language? This is investigated by means of an acoustic analysis of children's speech and an analysis of the speech of their primary caretakers, which will represent the adult target model. A second aim is to investigate whether congenitally hearing impaired children who received a cochlear implant very early in life show similar acoustic correlates of stress marking in their speech and display similar rhythmicity as their hearing peers.

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  • Research Project

An acoustic analysis of lexical stress and rhythm in early speech interactions of Dutch children and their primary caretakers: a longitudinal study. 01/10/2013 - 30/09/2015

Abstract

The main objective of this study is to investigate the acquisition of "lexical" stress and rhythm in the period when children produce canonical babbling and their first identifiable words. A good understanding of these phenomena in children's speech is of prime importance because it has been shown that prosody plays a cardinal role in children's language acquisition.

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  • Research Project

Speech accuracy in young children: hearing and hearing impaired toddlers with a cochlear implant. 01/01/2013 - 31/12/2016

Abstract

The aim of the current project is to investigate early sound development in two populations differing in access to spoken language: children with normal hearing (NH) and congenitally deaf children with "received hearing" due to cochlear implantation (CI) at an early age. In comparing speech accuracy of these two groups with "different degrees of hearing", we aim to gain a better insight into the role of the auditory perception system in language development.

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  • Research Project

Antwerp Yiddish Noun Plurals (AYNP). 01/09/2012 - 31/08/2013

Abstract

The project will explore structure and acquisition in contemporary Yiddish used by the Jewish Ultra-Orthodox community in Antwerp, Belgium. This community lives in a unique multilingual situation that includes three main languages: Yiddish and Dutch - two living languages competing as native tongues, and Loshn Koydesh (Classical Hebrew) - restricted only for praying and not used for daily communication. Our window onto native Antwerp Yiddish is the system of noun plurals, whereby a singular noun takes on a plural suffix. The aim of the project is two-fold: first, to describe the system of noun plurals as it is currently used by adults, taking into account the intensive contact with Dutch, and second, to understand how this system is acquired by children from the same community.

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  • Research Project

Morphosyntactic language skills in deaf children with cochlear implant: a cross-linguistic study on Dutch and German (MORLAS). 01/07/2012 - 30/09/2013

Abstract

The proposed project will investigate speech and language skills of cochlear implant children at the onset of their school career. The project will focus on Cochlear Implant children's achievements in a major aspect of language, its morphosyntax.

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  • Research Project

Child-directed speech and language development: hearing children of different SES backgrounds and deaf children with a cochlear implant. 01/01/2011 - 31/12/2014

Abstract

In this project we want to test the hypothesis that this relative poverty of the input is already manifest during the prelinguistic and early linguistic stages of language acquisition: particular aspects of the input make the discrimination of sounds more difficult, and make the segmentation of speech into sounds, and words, and phrases much more difficult.

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  • Research Project

Priming effects and dialect acquisition: rule-based versus exemplar-based accounts. 01/10/2008 - 27/08/2012

Abstract

This is a fundamental research project financed by the Research Foundation - Flanders (FWO). The project was subsidized after selection by the FWO-expert panel.

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  • Research Project

Sabbatical leave. 01/10/2008 - 30/09/2009

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  • Research Project

DUAL-PRO. Dual electric-acoustic speech processor with linguistic assessment tools for deaf individuals with residual low frequency hearing. 01/07/2008 - 30/06/2010

Abstract

To date, individuals with sensori-neural hearing loss may benefit from either acoustic stimulation (classical hearing aids) or electric stimulation (cochlear implants). Classical hearing aids are best suited for moderate and severe hearing losses and cochlear implants for profound losses. Cochlear implants enable profoundly deaf patients to reach high levels of speech intelligibility, but they are inadequate for the perception of music. The reason for this is that implants are conceived to code for the mid and high frequencies of sound ("spectral coding") since speech information is mainly contained in these frequencies. Implants are not performing well in the coding of low frequencies ("temporal coding"). These frequencies contain mainly information related to tonality, musicality, timbre, etc. Hearing aids perform much better in the temporal coding of low frequencies. Since most profoundly deaf persons have profound losses in the mid and high frequencies while they often have residual hearing in the low frequencies, the combination of the spectral coding of a cochlear implant with the temporal coding of a hearing aid, seems promising in improving the auditory performance of implant-wearers. In addition, temporal information seems of specific importance for the linguistic development in young children and it is anticipated that improving the low frequency perception may significantly enhance their linguistic capacities, thus decreasing their handicap and increasing the probability of mainstream integration. Main objectives of the proposed project: (i) to optimise deaf patients' hearing experience by developing a new hearing device which combines both types of stimulation in the same ear; (ii) to develop a test battery for prosody reception, i.e. the perception of language rhythm and melody; and (iii) to use this new prosody test battery as a quality measure for the current generation of cochlear implants and classical hearing aids, as well as for the newly developed hybrid electric-acoustic prototype.

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  • Research Project

Mind your Syntax. Oral language development and development of Theory of Mind in deaf children with a cochlear implantaat. 01/12/2007 - 30/11/2010

Abstract

Research in the field of developmental cognitive neuroscience has shown that audition and language exhibit plasticity, i.e. the ability to modify pre-existing neural synaptic connections dedicated to particular cognitive systems, depending on the quantity and quality of the environmental stimuli during a specific developmental stage. However, there is very little consensus in the literature with respect to the precise limits of these windows of opportunity. In this project we will tackle the issue of plasticity of the auditory system and its effect on language and general cognitive development. Two main hypotheses will be tested (i) the development of sensory, language and higher cognitive systems is triggered by qualitatively and quantitatively sufficient stimuli within a well-determined time window; and (ii) language plays a crucial role in higher cognitive development, more particularly in Theory of Mind development. These hypotheses will be tested on populations of children that have been deprived from sound due to congenital deafness. Comparative cohort studies of oral Dutch deaf children who have received cochlear implants at different ages will enable us to answer the central question of this project, namely whether cochlear implantation early in life leads to better auditory perception, providing the redundancy necessary for incidental language learning and higher cognitive development.

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  • Research Project

The influence of hearing on the early lexical development of deaf children with and without cochlear implants. 01/01/2007 - 31/10/2007

Abstract

In congenital deaf children with Cochlear Implants early language is acquired in two modalities, with both spoken words and signs; deaf children without CI normally acquire their language monolingually, namely by signs. By studying the early lexical acquisition of both groups longitudinally and by comparing the results with those of normally hearing children, this study will answer the question whether in children with CI a simultaneous acquisition with influence of one modality on the other is the case, or two separate developmental paths for both modalities.

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  • Research Project

Speech and language acquisition in Dutch speaking children with different degrees of hearing: Hearing children and deaf children with a cochlear implant. 01/01/2006 - 31/12/2009

Abstract

The aim of this project is to investigate segmental, intrasyllabic and intersyllabic co-occurrence patterns in prelexical babbling, and the acquisition of phonological segments and patterns in the early lexical period. Longitudinal data of deaf children with a cochlear implant (implanted in the first/second year of life) will be compared with those of a hearing age matched cohort in order to establish if they develop language in the same sequence and according to the same patterns as hearing children, and whether the delay that older implanted children show in reaching language acquisition milestones, still exists for the very early implanted children.

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  • Research Project

Acoustic phonetic analysis of the speech of very young children with a cochlear implant. 01/10/2005 - 30/09/2009

Abstract

The aim of this project is to investigate acoustic-phonetic characteristics of the speech of young congenitally deaf children who received a cochlear implant in their first year of life. In particular the acoustic characteristics of their babbling will be investigated in order to detect discrepancies with the babbling of hearing infants. In addition we will analyze spontaneous speech of these children at the age of six, and investigate whether it displays the typical characteristics of "deaf speech", and we will try to relate these characteristics to the infants' vocalizations in their first year of life.

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  • Research Project

Variation in the pronounciation of Standard Dutch: schwa epenthesis in Flanders and The Netherlands. 01/10/2005 - 30/09/2008

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  • Research Project

Lexical and morphosyntactic development in young children with a cochlear implant : A crosslinguistic study of Dutch and Hebrew. 01/01/2005 - 31/12/2008

Abstract

The first aim of this project is to study patterns of productive spoken language acquisition in children who received a CI early in their second year of life. The children's language acquisition will be compared with that of a matched group of normaly hearing (NH) chiljren. The second aim of the project is to study language acquisition crosslinguistically: language acquisition will be compared of chldren acquiring Dutch and Hebrew as their native language. In the language specific part of the project as well as in the crosslinguistic part, we will focus on the following aspects: -The study of early lexical and morphosyntactic development of children with a Cochear Implantation (inl)lantation age: between 1 ;0 and 1 ;06); -Comparison of CI children with normal hearing children of the sam age/level of language acquisition; -Comparison of CI children and NH children's development in two typologically different languages, viz. Dutch and Hebrew, which enables the testing of specific hypotheses concerning the mechanisms of language acquisition..

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  • Research Project

Syntactic aspects of the impaired acquisition of determiners. 01/10/2004 - 30/09/2007

Abstract

The project aims at studying the developmental pattern of early morphosyntax in 3 groups of language-impaired children (children with SLI, classical hearing aids and a cochlear implant, CI) and to verify whether the results are related to the clinical characteristics of the children. We focus on one particular aspect of nominal syntax, i.e. the acquisition of determiners in SLI, HI and CI-children compared to a control group of normally developing hearing children. The following research questions will be addressed: (i) in which way does the acquisition of the determiner system in SLI-children differ from normally language developing children: is there a temporary or permanent delay in the projection of a syntactic D-level and if so, what is the cause for the delay?; (ii) does the syntactic development of CI-children surpass that of children who use conventional HA (cfr. Van den Broek 1998 contra Geers 2003 for speech perception and production)?; (iii) does the syntax of very early implanted CI-children develop at pace with that of a normal hearing control group or are there similarities with other language impairments which typically show grammatical deficits; (iv) which are the factors that positively influence the acquisition of determiner syntax in CI-children; (v) from a theory-internal point of view: is neurological maturation responsible for the projection of a D-position in syntax? Is it input-sensitive and therefore positively influenced by an increase in auditory perception?

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  • Research Project

A constructivist analysis of 'fillers' in Dutch child language. 01/10/2004 - 30/09/2007

Abstract

Young children often insert 'fillers' in their first multiwordutterances: vocalizations that do not correspond to conventional words. For instance, it is hard to determine the meaning of the syllables [m] and [\] in utterance (a). Fillers often have the shape of a syllabic nasal or a schwa, as in utterances (a) and (b). But sometimes they consist of several syllables, as in utterance (c). (a) [m] pick ['] flowers (English learning boy, age 1;6; from Peters and Menn, 1993) (b) ['] oiseau ['] vole (Frensh learning girl, age 1; from Veneziano and Sinclair, 2000) (c) [lala] open door (English learning girl, age 1;10; from Feldman and Menn, 2003) Fillers typically occur at positions that are occupied by function morphemes in the adult language (like articles or pronouns). They are instantiations of an important language learning mechanism that has only recently been recognized as such: 'form-driven' learning. 'Form-driven' learning entails that the child first acquires the form, and gets full grips on the meaning and function of this form only later on. In other words, the child has discovered sound material at particular positions in the input, but has not yet analyzed the form and the function of this material accurately. Nevertheless, the child tries to integrate these elements in her own speech utterances. Little by little the child discovers the full distribution, function and shape of what turns out to be function morphemes. This learning mechanism contrasts with function-driven acquisition, as is proposed by nativist theories: morphosyntactic acquisition is interpreted as a self-unfolding plan of morphosyntactic functions that need to be stuffed with lexical material. Until now, fillers in Dutch child language have not yet been studied (except in the limited analysis of Wijnen et al., 1994). The aim of this research project is to investigate the role of fillers in the acquisition of Dutch, and to analyze the mechanism of 'form-driven' learning from a constructivist perspective on language acquisition.

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  • Research Project

Database of 14th century non literary Dutch texts. Construction and linguistic exploration. 01/01/2004 - 31/12/2007

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Reduction Phenomena in present-day Standard Dutch in Flanders and the Netherlands. 01/10/2003 - 30/09/2005

Abstract

The aim of this project is the study of reduction phenomena in spontaneous (= non-read) Standard Dutch. Reduction is studied in mono-, bi- and trisyllabic words, especially in pronouns, suffixes and loan words. We use speech that is already collected, digitalized and transcribed for the Corpus Gesproken Nederlands (Spoken Dutch Corpus), and as a part of the VNC-project Variation in the pronunciation of Standard Dutch. The VNC-speech consists of interviews with teachers of Dutch. From the Corpus Gesproken Nederlands, three components are selected: speeches, (non-read) lectures and lessons from high school teachers (except for Dutch lessons). These three types of spontaneous speech are fully comparable: it is non-broadcast speech, produced by one speaker before an audience. A more specific aim of this project is to verify the claim that the pronunciation of highly educated speakers without linguistic training differs from the pronunciation of teachers of Dutch, who are often considered to be prototypical speakers of Standard Dutch. This project links up with the renewed interest in standard language, where variation patterns in Standard Dutch in Flanders and the Netherlands are studied from a perspective of convergence and divergence. This study is also in line with international research of variation in standard languages, e.g. in German (e.g. Germany, Austria, Switzerland) and in French (e.g. France, Canada, Belgium).

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  • Research Project

FLaVoR : Flexible Large Vocabulary Recognition : Incorporating linguistic knowledge sources through a modular recogniser architecture. 01/10/2002 - 30/09/2006

Abstract

In this project we investigate whether the 'all-in-one' strategy currently used in speech recognizers, in which task-specific, syntactic, and lexical knowledge are fused into a single model based on simple formalisms, can be replaced by a modular architecture in which apart from acoustic-phonetic and intonational features, also generic and domain-specific linguistic information sources can be used.

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Children's acquisition of phonotactic and prosodic knowledge: an empirist, inductive alternative for current nativist, deductive approaches. 01/10/2002 - 30/09/2004

Abstract

Optimality Theory (OT) is the central paradigm in current theorizing about phonological acquisition. OT is a deductive model: (a priori) linguistic knowledge is represented in the child's linguistic (grammatical) competence. In this project we explore an empirist, inductive alternative for this approach. An empirist, inductive model is defined as a model in which the mental lexicon is central in acquisition. Linguistic knowledge is collected and stored in the lexicon. The contrast between grammatical system and lexicon will be developed in according to four core dimensions: 1. Rules versus analogy 2. Stages versus lexical diffusion 3. Minimal versus maximal role for input 4. Competence versus processing We focus on the acquisition of phonotactic and prosodic knowledge, because these two areas are often presented as examples of deductive acquisition.

Researcher(s)

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  • Research Project

Speech and language acquisition of children with a cochlear implant. 01/10/2002 - 30/09/2003

Abstract

Speech and language development of cochleair implant children is investigated.The study specifically focuses on the effect of the age implantation : babies implanted during the first year of life (around 6 m.) are compared with babies implanted in their second year of life. The effects of the implant on the auditory and articulatory levels and on the babies' productive language acquisition is focussed on.

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    • Research Project

    Reduction Phenomena in present-day Standard Dutch in Flanders and the Netherlands. 01/10/2001 - 30/09/2003

    Abstract

    The aim of this project is the study of reduction phenomena in spontaneous (= non-read) Standard Dutch. Reduction is studied in mono-, bi- and trisyllabic words, especially in pronouns, suffixes and loan words. We use speech that is already collected, digitalized and transcribed for the Corpus Gesproken Nederlands (Spoken Dutch Corpus), and as a part of the VNC-project Variation in the pronunciation of Standard Dutch. The VNC-speech consists of interviews with teachers of Dutch. From the Corpus Gesproken Nederlands, three components are selected: speeches, (non-read) lectures and lessons from high school teachers (except for Dutch lessons). These three types of spontaneous speech are fully comparable: it is non-broadcast speech, produced by one speaker before an audience. A more specific aim of this project is to verify the claim that the pronunciation of highly educated speakers without linguistic training differs from the pronunciation of teachers of Dutch, who are often considered to be prototypical speakers of Standard Dutch. This project links up with the renewed interest in standard language, where variation patterns in Standard Dutch in Flanders and the Netherlands are studied from a perspective of convergence and divergence. This study is also in line with international research of variation in standard languages, e.g. in German (e.g. Germany, Austria, Switzerland) and in French (e.g. France, Canada, Belgium).

    Researcher(s)

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      Project type(s)

      • Research Project

      Psycholinguistics: Processing and Acquisition Processes of Reading and Spelling 01/01/2001 - 31/12/2005

      Abstract

      The purpose of this Scientific Research Community is to integrate the Flemish, Dutch, and international expertise in the study of (i) the acquisition of reading and spelling and (ii) the on-line processes in experienced readers and spellers. The central focus is the study of the reading and spelling of words (written word recognition and production), more particularly, the role of phonology and morphology and the importance of the way in which the spelling of the language represents these linguistic dimensions. Concrete goals are: the realisation of joint empirical work by several subteams of the Research Community (experiments, corpus analyses, simulation studies), more particularly within a cross-linguistic perspective, the exchange of expertise in the form of people and tools, and the organisation of workshops and one international conference.

      Researcher(s)

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      Project type(s)

      • Research Project

      Psycholinguistics: processing and acquisition aspects of reading and spelling. 01/01/2001 - 31/12/2005

      Abstract

      The purpose of this scientific research network is to integrate the Flemish, Dutch, and international expertise in the study of (i) the acquisition of reading and spelling and (ii) the on-line processes in experienced readers and spellers. The central focus is the study of the reading and spelling of words (written word recognition and production), more particularly, the role of phonology and morphology and the importance of the way in which the spelling of the language represents these linguistic dimensions. Concrete goals are: the realisation of joint empirical work by several sub-teams of the research network (experiments, corpus analyses, simulation studies), more particularly within a cross-linguistic perspective, the exchange of expertise in the form of people and tools, and the organisation of workshops and one international conference.

      Researcher(s)

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      • Research Project

      Text Analysis and Machine Learning for Prosody. 01/01/2001 - 31/12/2004

      Abstract

      The aim of the project is to perform empirical investigations to determine whether adequate prosody can be generated on the basis of two methods that have recently shown success in other language processing domains: (a) robust analysis of text by analyses and metrics from information retrieval and information extraction, and (b) advanced machine learning systems and meta learners.

      Researcher(s)

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      • Research Project

      Language acquisition by children with cochlear implants: A longitudinal investigation 01/01/2001 - 31/12/2004

      Abstract

      In this project we study the auditory development, the speech and language acquisition in congenital deaf children with a cochlear implant (CI) implanted during their second year of life. Our aim is to systematically investigate the effect of the CI on different aspects of language and speech development: ? The effect of a CI on the auditory level; ? The effect of a CI on the articulatory level (the speech); ? The effect of a CI on language acquisition and communicative development. In essence, we want to investigate how access to the auditory information evolves and what impact that access to spoken language has on the child's own spontaneous speech and language. The scientific aims of the research proposal are (i) descriptive and (ii) fundamental. (i) Descriptive: a longitudinal description of the auditory development and speech-, language- and comminicative development after a CI. On the basis of this description we will be able to provide an answer to the following questions: Does language acquisition after a CI proceed in a qualitatively and/or quantitatively similar fashion as that in normal hearing babies? What is the level of spoken language development in CI-babies, as compared to normal hearing babies? Is there a qualitatively and/or quantitatively difference in the auditory development, speech- and language development between babies, depending on the age at which they receive a CI? (ii) Fundamental psycholinguistic aims: ? Study of the perception of segmental and supra-segmental characteristics of speech in relation to its production: ? Study of the phonological development on the segmental and suprasegmental level, focussing on the evolution of truncation patterns. ? Study of the lexical and morphosyntactic acquisition, focussing on the evolution of `function words' or closed class words with respect to open class words, an opposition related to perceptual salience. ? Study of communicative development, focussing on (1) the use and place of speech versus (conventional) signs, (2) the use of interactional means (attention seeking/fixing/'), (3) the magnitude and use of types of interaction turns by child and adult conversation partner.

      Researcher(s)

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      • Research Project

      A computational psycholinguistic model of language acquisition. 01/10/2000 - 30/09/2012

      Abstract

      This project aims at developing a computational psycholinguistic model of children's primary language acquisition. Ultimately the model is meant to provide a computational psycholinguistic account of acquisition in a data-driven way, incorporating the structural aspects of input, the child's 'intake' of the input and the self-organizing mechanisms of the learner. The term 'computational psycholinguistic' is not only meant as a characterization of the type of theory to be developed, it also defines the methodology to be adopted: the acquisition of particular linguistic domains will be studied from a psycholinguistic perspective, viz. the investigation of child language corpora (and experimental testing of hypothesis), and from a computational perspective, viz. the use of artificial learning algorithms in simulations. Both methodologies will be implemented in an integrated fashion so as to maximize mutual informativeness and theoretical relevance. The relationship between the psycholinguistic and the computational perspective is twofold: (i) The articulation of a model of children's language acquisition in which structural aspects of the input language and the self-organizing mechanisms of the learner are related, acts as the unifying framework. (ii) Particular aspects of the acquisition of the phonology, lexicon and morphosyntax of Dutch will be studied both from a psycholinguistic and a computational perspective. Corpora will be used as primary data in psycholinguistic analyses and they will be used as input material for the artificial language learners. The performance of the latter can be evaluated using the actual acquisition patterns of the children studied.

      Researcher(s)

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      Project type(s)

      • Research Project

      The bottleneck of syntax in language technology research: integration of memory based machine learning in the AI-investigation of the Origins of Language. Optimising both paradigma through and for syntactic research. 01/10/2000 - 30/09/2002

      Abstract

      This project investigates the potential integration of two Artificial Intelligence domains by investigating the problematic role of syntax within both lines of research. Syntactic research within the subfield of Memory Based Reasoning is concerned with optimising two classification tasks: classification of segmentation (delimiting consituents) and classification of disambiguation (assigning grammatical labels).The robotic experiments that are being conducted within the Origins of Language research at the AI-lab (VUB), can likewise be interpreted as classification experiments. This classification task is problematic in both domains. Joint experiments, in which properties of both MBR and the OoL research will be combined, will try to attribute new insights in both research areas, so that a number of important limitations can be resolved.

      Researcher(s)

      Research team(s)

        Project type(s)

        • Research Project

        Children's acquisition of phonotactic and prosodic knowledge: an empirist, inductive alternative for current nativist, deductive approaches. 01/10/2000 - 30/09/2002

        Abstract

        Optimality Theory (OT) is the central paradigm in current theorizing about phonological acquisition. OT is a deductive model: (a priori) linguistic knowledge is represented in the child's linguistic (grammatical) competence. In this project we explore an empirist, inductive alternative for this approach. An empirist, inductive model is defined as a model in which the mental lexicon is central in acquisition. Linguistic knowledge is collected and stored in the lexicon. The contrast between grammatical system and lexicon will be developed in according to four core dimensions: 1. Rules versus analogy 2. Stages versus lexical diffusion 3. Minimal versus maximal role for input 4. Competence versus processing We focus on the acquisition of phonotactic and prosodic knowledge, because these two areas are often presented as examples of deductive acquisition.

        Researcher(s)

        Research team(s)

          Project type(s)

          • Research Project

          Phonetic characteristics of lexical tonal contrasts in Limburgs dialects. 01/01/2000 - 31/12/2001

          Abstract

          This project aims to draw up an explicit phonetic description of tonal contrasts in three dialects from the Limburg region as well as their interaction with the intonational system of the respective variants. The description is based on a data collection of speech materials which are analysed acoustically. This will generate hypotheses about phonetic form which are tested in perception experiments.

          Researcher(s)

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            Project type(s)

            • Research Project

            A computational psycholinguistic model of language acquisition 01/10/1999 - 30/09/2001

            Abstract

            This project aims at developing a computational psycholinguistic model of children's primary language acquisition. Ultimately the model is meant to provide a computational psycholinguistic account of acquisition in a data-driven way, incorporating the structural aspects of input, the child's 'intake' of the input and the self-organizing mechanisms of the learner. The term 'computational psycholinguistic' is not only meant as a characterization of the type of theory to be developed, it also defines the methodology to be adopted: the acquisition of particular linguistic domains will be studied from a psycholinguistic perspective, viz. the investigation of child language corpora (and experimental testing of hypothesis), and from a computational perspective, viz. the use of artificial learning algorithms in simulations. Both methodologies will be implemented in an integrated fashion so as to maximize mutual informativeness and theoretical relevance. The relationship between the psycholinguistic and the computational perspective is twofold: (i) The articulation of a model of children's language acquisition in which structural aspects of the input language and the self-organizing mechanisms of the learner are related, acts as the unifying framework. (ii) Particular aspects of the acquisition of the phonology, lexicon and morphosyntax of Dutch will be studied both from a psycholinguistic and a computational perspective. Corpora will be used as primary data in psycholinguistic analyses and they will be used as input material for the artificial language learners. The performance of the latter can be evaluated using the actual acquisition patterns of the children studied.

            Researcher(s)

            Research team(s)

              Project type(s)

              • Research Project

              The bottleneck of syntax in language technology research: integration of memory based machine learning in the AI-investigation of the Origins of Language. Optimising both paradigma through and for syntactic research. 01/10/1998 - 30/09/2000

              Abstract

              This project investigates the potential integration of two Artificial Intelligence domains by investigating the problematic role of syntax within both lines of research. Syntactic research within the subfield of Memory Based Reasoning is concerned with optimising two classification tasks: classification of segmentation (delimiting consituents) and classification of disambiguation (assigning grammatical labels).The robotic experiments that are being conducted within the Origins of Language research at the AI-lab (VUB), can likewise be interpreted as classification experiments. This classification task is problematic in both domains. Joint experiments, in which properties of both MBR and the OoL research will be combined, will try to attribute new insights in both research areas, so that a number of important limitations can be resolved.

              Researcher(s)

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                Project type(s)

                • Research Project

                Corpus Spoken Dutch - Flemish part. 01/06/1998 - 30/11/2003

                Abstract

                The Dutch-Flemish project `Corpus Spoken Dutch' aims at collecting 10 million spoken words of present day (standard) Dutch. This corpus will have important technological applications since it will play an essential role in the development of automatic speech recognition, and in this way it will prove to be invaluable in safeguarding the position of Dutch as a (minority) language in multilingual Europe. The corpus will be important for other disciplines as well: lexicography, teaching, children's speech and language development, sociolinguistics, psycholinguistics, phonetics and phonology and conversational analysis.

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                • Research Project

                Computational psycholinguistics : natural and artificial language acquisition and processing. 01/01/1998 - 31/12/2003

                Abstract

                The issue of abstract representations in the domains of language acquisition and adult language processing is addressed in this project. Is it possible to learn a subdomain of language without prior linguistic knowledge in this domein '? Can one achieve the final learning stage (adult performance) without developing abstract representations ? A new methodology will be used to study these questions. The research will explicitly combine the techniques that are used in three separate disciplines: language acquisition research, psycholinguistics, and artificial intelligence. Whereas the former two take the real language learner/user as their object of study, the latter one studies the artificial language learner/user. Thus far artificial learning models have always been used to simulate effects observed in actual language use. Whereas simulation reveals the computational power of the learning system and suggests interesting hypotheses on the real language learner/user, it does not falsify hypotheses generated in, for instance, psycholinguistic work. In our research we want to use artificial language learners/users in a radically different way. Apart from having them simulate effects from real language use we want to isolate factors that affect the models behaviour and then study the effects of these same factors in psycholinguistic experiments and in language acquisition data. In case of a different outcome, the effects observed in real language users can then be used to adept the architecture of the artificial learning model and see whether its performance can eventually be matched to that of the language user. This method of relating the results from acquisition and psycholinguistic research to computational work and vice versa is essentially a heuristic for discovering properties of the representational architecture for language in the real language learner/user. This basic issue, and the methodology to study it, will be approached in two linguistic domains: phonology and inflectional morphology. In phonology, the linguistic representation of stress patterns, phonotactic restrictions, and syllable structure will be studied. In morphology, irregularity effects in the past tense forrnation in Dutch will be used to study the issue of the single-route versus dual-route architecture (i.e., rules for regular forms' a lexicon for the irregular ones). A study of the factors causing interference errors in the spelling of (highly regular) past tense forms in Dutch (regular forms affecting other regulars) will shed light on the issue.

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                • Research Project

                The standerd of Dutch pronunciation in The Netherlands and in Belgium. Comparative research on the pronunciation of Standard Dutch by radio newsreaders in the Netherlands and in Belgium. 01/01/1998 - 31/12/2001

                Abstract

                The goal of my research is to compare the pronunciation of Standard Dutch in the Netherlands and in Belgium. More specifically I want to compare the Dutch standard of pronunciation and the Flemish standerd of pronunciation. The standerd in Flanders is the VRT-Dutch (Flemish Radio and Television). The NOS-Dutch (National Broadcast Foundation) was chosen as the standard for the Netherlands. IT need a very formal speechvariant (read Standard Dutch), because what I want to find is an (abstract) standard of pronunciation. News broadcasts of the VRT- and NOS-radio fit into this profile very well. The main question of my research is the following: Which are the differences between northern and southern Standard Dutch? How is it that one can immediately hear whether a person lives in the Netherlands or in Flanders? I will try to answer these questions by means of a detailed perceptive and acoustic research on the pronunciation of vocals, consonants, intonation patterns, ... in the speech of a few VRT- and NOS-radio newsreaders.

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                  • Research Project

                  Crosslinguistic Project on Pre- and Protomorphology in Early Language Acquisition. 01/09/1997 - 31/08/1999

                  Abstract

                  The European Pre- and Protomorphology project is an international research project headed by Prof. W. Dressler (Vienna) on the acquisition of morphophonology. The aims of the project are: (1) Investigation of the earliest stages of morphophonological acquisition and development; (2) crosslinguistic studies of early morphophonological development. In the project the following languages are represented: Bask, Corean, Croatian, Dutch, Estonian, French, Georgian, German, Greek, Hebrew, Huichal, Hungarian, Italian, Lithuanian, Maltese, Polish, Russian, Slovenian, Spanish, Swedish, Thai, Tunesian Arabic, Turkish, Ukranian, Yucatec Maya.

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                    • Research Project

                    01/01/1997 - 31/12/1997

                    Abstract

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                      • Research Project

                      A data-driven model of language acquisition: Computational and psycholinguistic investigations. 01/01/1996 - 31/12/2000

                      Abstract

                      The aim of the project is the development of a computational psycholinguistic model of morphosyntactic aspects of language acquisition. This includes a psycholinguistic investigation of the acquisition of morphosyntax, and more specifically the acquisition of the morphological and distributional reflexes of the feature 'finite' in Dutch. A computer model of these linguistic phenomena will be implemented in which the principles of similarity based reasoning will be represented.

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                        Project type(s)

                        • Research Project

                        Electronic archive for language technology of Dutch. 01/10/1995 - 31/12/1996

                        Abstract

                        The aim of this project is to install, develop, enrich, maintain and make available an electronic server for software, data collections, knowledge bases and corpora related to language technological research (esp. focused on Dutch). This server is crucial for the development of language for Dutch because it enhances the reusability of research results, it prevents the unproductive repetition or overlap of research efforts and can serve as a didactic source of information for students of language technology and computational linguistics.

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                          • Research Project

                          Memory based acquisition and processing of morphological and syntactic knowledge for language technological applications. 01/07/1995 - 30/06/1996

                          Abstract

                          The project aims at developing a computational model of morphophonological and syntactic knowledge acquisition and processing using the principles of memory-based reasoning. The induction of linguistic knowledge is meant to be domain and language independent.

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                            • Research Project

                            Computational Linguistics and Language technology. 01/01/1995 - 31/12/1999

                            Abstract

                            The proposed research community has as its goal to promote the integration and strenghtening of the Flemish expertise in the field of the automatic processing of language (both the theoretical and the applied perspective). The Flemish participants represent complementary contributions to fundamental and applied research in natural language processing. The other participants have been selected for their international status, their existing cooperation with the Flemish partners, and their complementarity to the Flemish partners. The next five years, the cooperation will try to achieve the following goals: (1) Integration, coordination and international embedding of Flemish research in the field. (2) Collection of resources for Flemish language technology, within the framework of European standardization efforts.

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                              • Research Project

                              FONILEX: a pronunciation lexicon of Dutch. 01/01/1995 - 30/06/1997

                              Abstract

                              The aim of the project is the compilation of a pronunciation lexicon of a representative number Dutch word forms and their Flemish pronunciation. The output of the project, a database, is meant to be used in speech research, i.a. phoneme based speech recognition, text-to-speech synthesis, integrated speech and language processing.

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                                • Research Project

                                The acquisition of linguistic knowledge : cognitive and language technological aspects. 01/01/1994 - 31/12/1997

                                Abstract

                                In the present research project we aim at studying the process of language acquisition adapting a data-driven approach and to conduct experiments with artificial learning algorithms in which cue-based competitive learning can readily be implemented.

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                                  • Research Project

                                  01/01/1990 - 31/12/1990

                                  Abstract

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                                    • Research Project

                                    01/01/1990 - 31/12/1990

                                    Abstract

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                                      • Research Project

                                      A developmental psycholinguistic investigation of early language acquisition : towards a functional explanation. 01/10/1989 - 30/09/1999

                                      Abstract

                                      The early stages of language acquisation are investigated with special attention for the interplay between the social-interactional and cognitive determinants of the acquisition process. Investigations are mainly longitudinal and observational, supplemented by experimental tests of selected hypotheses. For data manipulation and analysis software tools from the CHILDES library are used.

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                                        • Research Project