Testing the bilingual advantage for executive function: insights from hearing children who are native signers

ABSTRACT

Bimodal bilingualism involves the use of a sign language and a spoken language, and offers a unique opportunity to explore the cognitive effects of growing up bilingual. The aim of this study was to investigate the relationship between bimodal bilingualism and executive function (EF) in hearing children who are native users of a sign language. We studied three groups of children: bimodal bilinguals (users of a sign language and a spoken language), unimodal bilinguals (users of two spoken languages), and monolinguals, performing three cognitive tasks to measure different components of EF: visuospatial working memory (Odd One Out task), cognitive flexibility (Children’s Colored Trails Test) and conflict resolution (Simon task). All groups of children obtained similar scores on the Odd One Out task and the Children’s Colored Trails Test. Bimodal bilinguals displayed distinct patterns of conflict resolution in comparison to monolingual children: bimodal bilinguals had better overall accuracy and slower overall reaction time in the Simon task. The subsequent analysis did not find a straightforward trade-off between speed and accuracy. These results suggest that bimodal language experience and/or visual-spatial language usage may explain the small bimodal bilingual advantage in the Simon task that we observed in hearing children who are native signers.

KEYWORDS:

• Bimodal bilingualism
• sign language
• hearing native signer
• executive function
• bilingual advantage

Acknowledgements

We want to thank: dr. Kate Rowley, Prof. Chloe Marshall, dr. Eva Gutierrez-Sigut, Sannah Gulamani and Daniel Diaz. We gratefully acknowledge all our participants.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data accessibility statement

Partial datasets generated during the current study are available from the corresponding author upon request.

Additional information

Funding

This research was supported by the Polish Ministry of Science and Higher Education under the Mobility Plus program, grant number 1669/MOB/V/2017/0 (grant was implemented at the University of the National Education Commission, Cracow, Poland).

Notes on contributors

Justyna Kotowicz

Justyna Kotowicz is assistant Professor at the University of Silesia in Katowice, Poland. She is focused on studies on: bimodal bilingualism, bilingual education for deaf students, cognitive control and sign language, neuronal and behavioral underpinning of reading in deaf signers.

Bencie Woll

Bencie Woll is Professor of Sign Language and Deaf Studies at University College London, UK. Her research focuses on sign language as a model to understand human language generally: sign language acquisition; neuroimaging studies of commonalities in processing spoken and signed languages; the influence of modality of communication on language structure; sociolinguistics of deaf communities.

Gary Morgan

Gary Morgan is Professor of Psychology at the University Oberta Catalunya in Spain. His scientific interests include: signed and spoken language acquisition, specific language impairment in signing children and gestures in hearing people with language difficulties, relationships between language and cognitive development in Theory of Mind and Executive Function and variability in how completely deaf children learn spoken language.