Language and Theory of Mind: A Study of Deaf Children


  • This research was funded by NIH Grant DC02872 “Language and Theory of Mind in Deaf Children” to Smith College, the University of Colorado, Boulder, and Boston University. We are grateful to all the consultants and research assistants who made the study possible: Ben Bahan from Boston University and Gallaudet University; Elaine Gale, Jenny Lin, Sarah Hafer, and Gene Mirus from the University of Colorado in Boulder; Marcia Unger, Lana Cook, Patrick Costello, and Marie Philip from Boston University; and Jennifer Friedman, Roberta Giordano, and Jennie Pyers from Smith College. We would like to thank the schools, families, and children for participating in this study, especially given the amount of time and testing we needed.

concerning this article should be addressed to Brenda Schick, Speech, Language, & Hearing Sciences, University of Colorado, 2501 Kittredge Loop Road, SLHS, Boulder, CO 80309-0409. Electronic mail may be sent to


Theory-of-mind (ToM) abilities were studied in 176 deaf children aged 3 years 11 months to 8 years 3 months who use either American Sign Language (ASL) or oral English, with hearing parents or deaf parents. A battery of tasks tapping understanding of false belief and knowledge state and language skills, ASL or English, was given to each child. There was a significant delay on ToM tasks in deaf children of hearing parents, who typically demonstrate language delays, regardless of whether they used spoken English or ASL. In contrast, deaf children from deaf families performed identically to same-aged hearing controls (N=42). Both vocabulary and understanding syntactic complements were significant independent predictors of success on verbal and low-verbal ToM tasks.