research projects

the 2in1 project
How does the bilingual mind cope with two languages at the same time? Is it possible for bilinguals to keep their two languages apart? To what extent can a bilingual’s two languages influence each other? Whilst the general consensus in the field of bilingual first language acquisition is that there is separate development of the two languages, there is also clear evidence that under certain circumstances, one language may influence the other. The exact mechanisms by which such crosslinguistic influence occurs, however, remain unknown. In this 5-year project, funded by an NWO VIDI grant, we’ll determine the extent of crosslinguistic influence in production and comprehension, at the lexical and sentential level, across a range of populations and linguistic phenomena, and using offline and online measures. Taken together, the results will allow us to develop a new and comprehensive account of crosslinguistic influence. 

To find out more, please consult the project webpage here.
language dominance project
In a recent paper investigating language dominance in English/Dutch bilingual toddlers (Unsworth, 2015, in Silva-Corvalan & Treffers-Daller (Eds.), see publications page). I argued that amount of exposure may be used as a proxy for language dominance. In that study, I presented data from balanced and Dutch-dominant children showing a clear relation between relative bilingual proficiency (as measured by MLU differentials in the two languages) and bilingual experience (as measured by amount of exposure and children’s output or language use). In a follow-up, I’ve been collaborating with Vicky Chondrogianni and Barbora Skarabela at Edinburgh University to collect data from English-dominant English/Dutch bilingual children in the UK. 

tweetalig primair onderwijs / bilingual primary education
The Dutch Ministry for Education, Culture and Science announced in summer 2013 that 
they will carry out a pilot project on bilingual primary education. In this project, 18 
primary schools in the Netherlands will use English as the language of communication for between 30% and 50% of their teaching time. Rick de Graaff and I were project leaders for the first stage of the research part of this project. The project report was published in March 2014 and can be found here (in Dutch). We are both also involved in the larger consortium including Radboud University, KBA Nijmegen, Expertisecentrum Nederlands and Utrecht University in the research project evaluating the progress of the pilot from 2014 to 2019, FOTO Flankerend Onderzoek Tweetalig primair Onderwijs. 

Quality of language input in bilingual acquisition (Project QUalIBI)
Whilst exposure to two languages is necessary to become bilingual, it is not a guarantee for successful acquisition; there is considerable individual variation in the extent to which children raised in a bilingual environment acquire their two languages. Developing sufficient knowledge of the majority language in the preschool years is particularly important, as failure to do so can affect chances of later educational success. Various child-internal and child-external factors have been shown to affect bilingual language development, and these have been investigated from both a pedagogical and linguistic approach. Project QuaLIBi was a 2-year project (September 2012-August 2014) which drew on both approaches, continuing this line of research by investigating the role of input quality on bilingual language development using a variety of experimental techniques, examining data from infants to preschoolers, and assessing knowledge in a number of linguistic domains, whilst at the same time taking into account individual characteristics such as working memory and SES. Project QuaLIBi consisted of three part-projects:

Language learning from variable input by bilingual children --- Elise de Bree
Input and output variability in bilingual preschoolers --- Sharon Unsworth
Measuring input variability to bilingual infants --- Josje Verhagen

We are also conducted an additional part-project addressing similar questions in bilingual and trilingual children acquiring Dutch and English in a bilingual daycare setting, the results of which were presented at ISB10 in 2015. For further details about output from this project, see my publications and whereabouts pages.

early child bilingualism project
This project explored the effect of age of onset and amount and quality of exposure on the linguistic development of bilingual English/Dutch children in their acquisition of word order, subject-verb agreement, grammatical gender, specific indefinites and vocabulary. More specifically, we compared simultaneous and successive bilingual children, with a particular focus on ‘early successive bilinguals’, that is, children whose age of first exposure to their second language falls between 1 and 4 years old, an as yet largely unexplored population. In addition, the effect of amount of exposure (both at the current moment and over time) and quality of exposure (how much input comes from native speakers) is assessed using a detailed parental questionnaire. Amongst other things, the project explored whether these various factors affect different linguistic properties similarly and to what extent any effects are mitigated for example by age of acquisition (early vs. late phenomena) and the linguistic domain involved (morphosyntax, syntax-semantics, lexicon). For findings and publications relating to this project, please see my publications page.

This project was funded by the Netherlands Organisation for Scientific Research (NWO) with a VENI Innovational Research Incentives Scheme award to Sharon Unsworth and an International Programme award to Leonie Cornips (Meertens) and Aafke Hulk (University of Amsterdam). From 2008 to 2010, the project was run at the Meertens Institute and Utrecht University in collaboration with a partner project on English/Greek bilingual children at the University of Edinburgh (Antonella Sorace and Froso Argyri) and Aristotle University of Thessaloniki (Ianthi Tsimpli). From 2010 to 2012, the project continued at Utrecht University.

foreign languages in primary school project
Over the past few years, an increasing number of primary schools in the Netherlands have started to teach a second language (usually English) from grade 1 (age 4), so-called vervroegd vreemdetalenonderwijs (VVTO). The implementation of VVTO varies from school to school. For example, the amount of time ranges from 30 minutes to 2 or more hours per week. Furthermore, a considerable amount of variation teachers’ English language proficiency. This project investigated the effect of these various factors (amount of exposure, teachers’ proficiency level, starting age) by tracking the development of more than 200 children in their English grammar, phonology and vocabulary. In addition, children’s Dutch language development was also tested. 

This project was funded by a grant from the Dutch Ministry for Education, Culture and Science to Kees de Bot (University of Groningen) and Sharon Unsworth from 2009 to 2012. It was carried out by PhD student Liv Persson (Utrecht) and research assistant Tineke Prins (now at Radboud University Nijmegen). For findings and publications relating to this project, please see my publications page.