Impact of language abilities on exact and approximate number skills development: evidence from children with specific language impairment.

Purpose: Counting and exact arithmetic rely on language-based representations, whereas number comparison and approximate arithmetic involve approximate quantity-based representations that are available early in life, before the first stages of language acquisition. The objective of this study was to examine the impact of language abilities on the later development of exact and approximate number skills.

Method: Twenty-eight 7- to 14-year-old children with specific language impairment (SLI) completed exact and approximate number tasks involving quantities presented symbolically and nonsymbolically. They were compared with age-matched (AM) and vocabulary-matched (VM) children.

Results: In the exact arithmetic task, the accuracy of children with SLI was lower than that of AM and VM controls and related to phonological measures. In the symbolic approximate tasks, children with SLI were less accurate than AM controls, but the difference vanished when their cognitive skills were considered or when they were compared with younger VM controls. In the nonsymbolic approximate tasks, children with SLI did not differ significantly from controls. Further, accuracy in the approximate number tasks was unrelated to language measures.

Conclusions: Language impairment is related to reduced exact arithmetic skills, whereas it does not intrinsically affect the development of approximate number skills in children with SLI.