IOE - Faculty of Education and Society


Raising bilingual children

Researching the effects of exposure to a bilingual environment on cognitive development in infants.

The project was funded by the British Academy/Leverhulme Trust and ran from 2016 to 2017.

Project aims

This research project aimed to investigate possible differences in cognitive development between young children raised in monolingual and multilingual environments. Whereas, the literature often reports cognitive advantages for bilingual speakers at later stages of life, little is known about how the exposure to different languages can affect the cognitive system at very early stages of life. As planned, we tested 56 babies aged 8-10 months old, half of them raised in bilingual families, administering a range of cognitive tasks designed to measure attention to faces, executive function, audio-visual speech integration with eye-tracking methodology.

Project findings

Infants are naturally attracted to human faces. It has been observed that infants orient their visual attention on faces quicker than on objects and that they spend longer looking at faces than objects. 

In one of our studies, we have demonstrated that infants growing up in a bilingual environment orient their attention to faces even faster than monolinguals, and they scan faces even more extensively than monolinguals. Because these infants are learning two spoken languages at the same pace as monolinguals learn a single language, they may use visual cues of articulation to support their learning. This could increase their attention to faces, even when these are only presented as pictures. These results suggest a close association between face processing and language development in social communication. 

In a second study, we used eye-tracking and a McGurk paradigm to study face scanning patterns when 7-to-10-month-old infants were viewing articulation of audio visually congruent and incongruent syllables. We found that monolingual infants decreased their attention to the mouth and increased their attention to the eyes of speaking faces when presented with incongruent articulation typically leading to the McGurk illusion in adulthood. In bilinguals, no differences in face scanning patterns were observed between audio visually congruent and incongruent articulation, suggesting that the increased variability in their speech experience may lead to more tolerance to articulatory inconsistencies. These results suggest that the development of audio-visual speech perception is influenced by the infant’s language environment.


Principal Investigator: Dr Roberto Filippi - IOE, UCL's Faculty of Education and Society 

Co-Investigator: Professor Peter Bright - Anglia Ruskin University, Cambridge


We are grateful to all our little participants and their parents for their help and enthusiasm in taking part in our research.

Research articles 

Mercure, E., Bright, P., Quiroz, I., Filippi, R. (2022). Effect of infant bilingualism on audiovisual integration in a McGurk task. Journal of Experimental Child Psychology

Mercure, E., Quiroz, I., Goldberg, L., Bowden-Howl, H., Coulson, K., Gliga, T., Filippi, R., Bright, P., Johnson, M.H., & MacSweeney, M. (2018). Impact of language experience on attention to faces in infancy: Evidence from unimodal and bimodal bilingual infants. Frontiers in Cognitive Psychology, 9, 1943.