Judging meaning: A domain-level difference between autistic and non-autistic adults.

We tested whether autistic adults would show selective difficulties across several tests of inferencing and social understanding in the context of average-range core language ability. One-hundred and ninety-one participants completed an online battery, and data were analysed using confirmatory factor analysis. Results showed that vocabulary knowledge was separate from other measures, which collectively formed a 'receptive communication' factor. Autistic people underperformed on the 'receptive communication' factor but showed more advanced vocabulary knowledge than non-autistic participants. Lower performance among autistic adults on the test battery predicted face-to-face communication difficulties measured by self-report and researcher ratings, with moderate effect sizes. Follow-up analysis indicated three further findings. We hypothesized that differences would arise from an isolated 'theory of mind' difficulty in autistic people, but instead the data suggested more general information-processing differences when making judgements about communicative stimuli. Second, substantial group differences on a test of implied meaning were only partly explained at the factor level, suggesting that multiple cognitive influences underpinned these differences. Finally, autistic women tended to perform better than autistic men. Our results support the idea of a subtle domain-level difference in pragmatics in autistic people, while questioning the basis of this difference and highlighting substantial variability in skills across groups.