Theory of mind
Hoffmeister co-wrote the article "Language and Theory of Mind: A Study of Deaf Children" with Brenda Schick, Peter De Villers and Jill De Villers. The article summarized their study on Theory of mind (ToM) abilities in deaf children. 176 deaf children of varying ages participated in the study, with some as old as eight years of age and some as young as three. The children either used American Sign Language (ASL) or oral English, and some had hearing parents, while others had deaf parents. The study concluded that "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)." Moreover, both understanding of syntactic and vocabulary were predictors of verbal and low-verbal ToM tasks success.