Background: Autistic people without intellectual disabilities have increased perceptual capacity: they can process more information at any given time compared to non-autistic people. We examined whether increased perceptual capacity is evident across the autistic spectrum (i.e. for autistic people with intellectual disabilities) and whether it is…

Two experiments investigated perceptual primacy of dimensional and similarity relations in stimulus classifications of younger and older subjects. Results support a differential-sensitivity view of perceptual development which asserts that individuals at all ages primarily perceive and use separate relations. (RWB)