Autistic Individuals' Categorical Induction Abilities Improve by Mid-Adolescence.

PURPOSE: Categorical induction, the ability to transfer a known category's properties to a new category member, develops early and robustly in typically developing (TD) children but has proven challenging for autistic children and adolescents. We investigated whether autistic and TD adolescents might perform similarly on a categorical induction task when expressive language was controlled for, and whether autistic and TD children's categorical induction abilities improved longitudinally. METHODS: Twenty-two TD and 20 autistic participants completed a 'Diversity' categorical induction task as adolescents. For the longitudinal analysis, we examined a subset (19 TD and 14 autistic participants) who had also completed an 'Early' categorical induction task as five-to-seven-year-olds. RESULTS: When expressive language was controlled for, groups did not statistically differ on categorical induction performance in adolescence. Expressive language also predicted performance above and beyond nonverbal IQ in both groups. In the longitudinal analysis, we observed that both groups' categorical induction performance significantly improved over time, and the magnitude of improvement did not differ by group. CONCLUSIONS: Contrary to previous literature on this subject, our findings suggest that categorical induction is not out of reach for autistic individuals; accounting for differences in expressive language between groups, autistic adolescents' categorical induction performance mirrored that of their TD peers. Furthermore, our longitudinal analysis clarifies that the same autistic individuals who previously struggled with categorical induction could become more consistent.