Idiom and proverb processing in autism: a systematic review and meta-analysis

Abstract Figurative language processing impairments in autism have been widely demonstrated, and considered a defining feature of autism. Studies this area often consider different types figurative together, less attention has paid to identifying the factors that might contribute difficulties specific language. Here we present preregistered systematic review meta-analysis studies assessing comprehension idioms proverbs spectrum disorder (ASD) as compared typically developing (TD) individuals. Idioms are used multi-word expressions, which understood by using contextual information. Proverbs related type fixed, figurative, formulaic expression sentential form, linked with wisdom. represent forms more conventionalized frequently opaquer than metaphors, pointing unique way they processed conversational contexts. Our analysis encompassed total 11 from 10 papers (involving 235 autistic 224 TD individuals), met our inclusion criteria (the ASD groups were matched on both chronological age intelligence). The accuracy data revealed group difference favouring over group, medium effect size, no indication publication bias. Participants’ was unrelated magnitude differences, but there trend for smaller differences case participants higher (verbal) intelligence. We discuss these findings reference theories nature