Performance of Theory of Mind Tests in Children and Language Understanding Ability

Objective: To investigate the relationship between vocabulary understanding ability and performance of theory-of-mind tests of children and to confirm the applicability of Chinese revision of Theory of Mind Tests in China. Methods: 100 children aged from 3 to 5 years in Harbin City in China completed the Chinese revision of Theory of Mind Tests and Peabody Picture Vocabulary Test(PPVT). Results:The pass rates of 'expression recognition' tests from 3 to 5 years groups were 100%, and that of 'expression reasoning' tests were 76%,97%,97%. There were 36%,76%,93% of children passed the 'place change' false belief tests and 15%,42%,59% of children passed the 'content change' false belief tests. From 3 to 5 years groups, significant differences of PPVT IQ were found between groups divided depending on different performances of false belief tests, such as that of children passed place change or not were 104.9±16.9 vs 97.0±15.8,106.7±17.6 vs 99.7±15.9(t=2.22,2.07, P0.05).Conclusions:The language understanding ability of children was related to the performances of false belief tests. Chinese revision of Theory of Mind Tests was applicable to Chinese children.