Do readers with autism make bridging inferences from world knowledge?

Individuals with autism frequently show impairments in text reading comprehension. This often is attributed to poor ability to draw inferences during reading and to inadequate access to relevant knowledge. The current study tested this hypothesis by measuring the time taken to read the same question, relating to either physical or social world knowledge, when it was either relevant or irrelevant to the bridging inference evoked by a preceding two-sentence vignette. In the study, 16 normally developing adolescents and 16 adolescents with autism were matched on word reading accuracy, chronological age, and vocabulary but differed significantly in text comprehension. A strong priming effect was found, robust over participants and over items; participants read those questions that were relevant to the inference evoked by the vignette faster than they read those questions that were irrelevant, and no interaction with group membership or type of knowledge was found. This indicates that readers with autism, just like controls, were activating appropriate world knowledge primed by implicit inferences while reading the vignettes. Thus, the comprehension problems in these readers cannot be attributed to an inability to make implicit inferences or to draw on relevant world knowledge. Instead, we suggest that these problems must be sought at a higher level of text processing.