Relationship between standard false belief, nonvocal false belief and guesser-knower tests in children with autism spectrum disorders

Approximately 80% of children with autism spectrum disorders (ASDs) fail to perform perspective taking as measured by false belief (FB) tests that require speech. Since children with ASDs exhibit a range of verbal abilities, it is possible that children with limited speech may be successful on false belief tests that do not require vocal responses. The present study examined the performance of children on five false belief tests that require different verbal skills. Eighteen children with ASDs (ages 5 years to 11 years 11 months) were tested on: (a) two standard FB tests that require children to answer questions vocally; (b) two nonvocal FB tests that allow children to point to visually displayed options when responding to questions; and (c) a nonvocal Guesser-Knower (GK) test designed to evaluate whether children are able to discriminate the relationship between seeing and knowing. Results indicate that: (a) performance did not differ significantly among the five different tests; (b) children with higher expressive language scores outperformed those with lower expressive language scores on all tests; (c) children with Asperger syndrome outperformed children with autistic disorder on all five tests; and (d) children with higher working memory scores outperformed children with lower working memory scores on all five tests.