Continuity and change in the development of category structure: Insights from the semantic fluency task

Children aged between 5 and 10 years old were tested on a semantic fluency (freelisting) task for two categories: animals and body parts. Additive tree analysis (Sattath & Tversky, 1977) was used to cluster items based upon both their proximity in the generated lists and their frequency of cooccurrence; the resulting trees, together with production frequency data, were compared across three age groups. For the animals category, this analysis revealed that although older children named proportionally more nonmammals, at all ages children tend to cluster animals according to their environmental context. For body parts, the analysis showed more parts, particularly internal organs, named with age and a cluster of face parts generated by all age groups. A novel feature of the current research was the use of statistical measures of additive tree similarity. The results are discussed with respect to theories of developmental change in the organisation of conceptual memory, and are viewed as supporting an assumption of continuity with age in the use of schematic relations in category structure. Insights are drawn from connectionist modelling to help explain the persistence, throughout childhood, of early forms of memory organisation.