Development of Phonological Constancy: 19-Month-Olds, but Not 15-Month-Olds, Identify Words in a Non-Native Regional Accent


  • This research was funded by ARC Discovery Grant DP0772441 (Chief Investigators: C. Best & C. Kitamura) and NIH Grant DC000403 (Principal Investigator: C. Best), with contributions from the Dean of the College of Arts at the University of Western Sydney, and the Marcs Institute via Research Training Scheme funds. Acknowledgment is also given to the first author's support from an EIPRS scholarship from the Australian Department of Education, Employment & Workplace Relations. We express our gratitude to our toddler participants and their parents for their invaluable contributions and interest in the research. We also thank Rikke Bundgaard-Nielsen, Lidija Krebs-Lazendic, Anna Notley, and Bethany Wootton for their work in stimulus development, Alizee Foucher, Carly Hayman, and Michelle Pal for their assistance in running the study, and Lauren Tornatore for her help with earlier pilot work. Finally, we thank Damien Smith for feedback on earlier versions of this manuscript.


By 12 months, children grasp that a phonetic change to a word can change its identity (phonological distinctiveness). However, they must also grasp that some phonetic changes do not (phonological constancy). To test development of phonological constancy, sixteen 15-month-olds and sixteen 19-month-olds completed an eye-tracking task that tracked their gaze to named versus unnamed images for familiar words spoken in their native (Australian) and an unfamiliar non-native (Jamaican) regional accent of English. Both groups looked longer at named than unnamed images for Australian pronunciations, but only 19-month-olds did so for Jamaican pronunciations, indicating that phonological constancy emerges by 19 months. Vocabulary size predicted 15-month-olds' identifications for the Jamaican pronunciations, suggesting vocabulary growth is a viable predictor for phonological constancy development.