title: A cognitive complexity metric applied to cognitive development.
abstract: Two experiments tested predictions from a theory in which processing load depends on relational complexity (RC), the number of variables related in a single decision. Tasks from six domains (transitivity, hierarchical classification, class inclusion, cardinality, relative-clause sentence comprehension, and hypothesis testing) were administered to children aged 3-8 years. Complexity analyses indicated that the domains entailed ternary relations (three variables). Simpler binary-relation (two variables) items were included for each domain. Thus RC was manipulated with other factors tightly controlled. Results indicated that (i) ternary-relation items were more difficult than comparable binary-relation items, (ii) the RC manipulation was sensitive to age-related changes, (iii) ternary relations were processed at a median age of 5 years, (iv) cross-task correlations were positive, with all tasks loading on a single factor (RC), (v) RC factor scores accounted for 80% (88%) of age-related variance in fluid intelligence (compositionality of sets), (vi) binary- and ternary-relation items formed separate complexity classes, and (vii) the RC approach to defining cognitive complexity is applicable to different content domains.
authors.affiliation: School of Applied Psychology, Griffith University, Gold Coast Campus, PMB 50, Gold Coast Mail Centre, Qld. 9726, Australia. g.andrews@mailbox.gu.edu.au
authors.forename: Glenda
authors.initials: G
authors.lastname: Andrews
authors.forename: Graeme S
authors.initials: GS
authors.lastname: Halford
mesh_terms: D002648:Child; D002657:Child Development / Q000502:physiology; D002675:Child, Preschool; D003071:Cognition / Q000502:physiology*; D003210:Concept Formation / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D011897:Random Allocation