Counting, Cardinality and Conservation in Autistic Children

This study examined the understanding of cardinality and conservation in children with and without autism (aged 4-7 years, without intellectual disability), and its relation to counting strategies. A total of 82 children participated in the study, including 41 autistic children (36 boys, 5 girls) and 41 age- and sex-matched non-autistic peers. While both groups demonstrated similar mastery of cardinality, autistic children showed lower performance in conservation tasks. Response times were longer in autistic children during counting tasks. Concerning counting strategies, autistic children relied more on verbal counting with pointing (VCP) and used the rapid recognition strategy (N) less frequently, even for small canonical sets. While both strategies (N and VCP) supported cardinality in both autistic and non-autistic children, only the N strategy appeared closely linked to successful conservation performance. These findings highlight two areas of relative difficulty for some autistic children and point to the potential of targeted interventions to strengthen foundational numerical skills and support later mathematical development.