Hemispheric Processing of Idioms and Irony in Adults With and Without Pervasive Developmental Disorder.

Saban-Bezalel et al. (2015) watched adults with pervasive developmental disorder and neurotypical adults while they listened to idioms and ironic jokes.

The team used brain scans to see which side of the head lit up during each task.

Everyone answered questions to show they understood the phrases.

Both groups got about the same number of answers right.

Typical adults used mostly the right side of the brain for these jokes and sayings.

Adults with PDD used both sides equally, yet still scored just as well.

Deliens et al. (2018) seems to disagree. They gave adults with ASD harder irony tasks and saw clear mistakes.

The gap is in the task: Ronit used simple idiom-plus-irony lists; Gaétane used stories that forced the listener to read minds. Same people, different demand, different outcome.

Lampri et al. (2024) and Rundblad et al. (2010) show that autistic children do struggle with metaphors. The adult success Ronit found may reflect years of quiet compensation, not vanished deficits.

Your adult clients might understand sarcasm even if their brain route looks odd. Do not drop figurative-language goals at once—test with both easy lists and mind-reading stories. If they fail only the harder type, teach perspective-taking, not just phrase memory.