%A Visser,Ingmar %A Raijmakers,Maartje %D 2012 %J Frontiers in Psychology %C %F %G English %K category learning,multiple systems,rule-based representation,similarity-based representation,strategy analysis %Q %R 10.3389/fpsyg.2012.00073 %W %L %M %P %7 %8 2012-March-19 %9 Original Research %+ Dr Ingmar Visser,Universiteit van Amsterdam,Department of Psychology,Developmental Processes Research Group,Amsterdam,1018XA,Netherlands,i.visser@uva.nl %# %! Developing Representations of Compound Stimuli %* %< %T Developing Representations of Compound Stimuli %U https://www.frontiersin.org/articles/10.3389/fpsyg.2012.00073 %V 3 %0 JOURNAL ARTICLE %@ 1664-1078 %X Classification based on multiple dimensions of stimuli is usually associated with similarity-based representations, whereas uni-dimensional classifications are associated with rule-based representations. This paper studies classification of stimuli and category representations in school-aged children and adults when learning to categorize compound, multi-dimensional stimuli. Stimuli were such that both similarity-based and rule-based representations would lead to correct classification. This allows testing whether children have a bias for formation of similarity-based representations. The results are at odds with this expectation. Children use both uni-dimensional and multi-dimensional classification, and the use of both strategies increases with age. Multi-dimensional classification is best characterized as resulting from an analytic strategy rather than from procedural processing of overall-similarity. The conclusion is that children are capable of using complex rule-based categorization strategies that involve the use of multiple features of the stimuli. The main developmental change concerns the efficiency and consistency of the explicit learning system.