Mentally Retarded Children's Study On The Concept Of Contact Type Classification Ability

The conventional view of a category is a set of objects or entities that share anessential core or are similar in some perceptual, biological, or functional properties.The process of forming category involves two concepts: concept and classification.Concept is an abstract or general idea inferred or derived from specific instances.Classification is a process to form a category through comparing things concepts bysimilarities and differences.Researchers in conceptual development have identified several category typesthat children may use to classify things, eg taxonomic categories, thematic categories,script category, ad hoc category. Taxonomic categories are usually organized intohierarchies of increasingly abstract categories, such as terrier-dog-animal. Thematiccategories group objects that are associated or have a complementary relationship;they often are spatially and temporally contiguous. Items in a script category need notbe spatially or temporally contiguous. Script categories include items that play thesame role in a routine or event such as breakfast time or a birthday party. However,researchers about this way of classification of children in China are little, let alone thestudy on the mental retarded children.This research explored children’s use of multiple forms of conceptualorganization. In this study,1017-15years old mental retarded children from twoschools were presented with pictures of three pictures and asked to pick two of themthat went together. Experiment1was free association to examine the concept types inthe minds of children. Experiment2was designed to examine the ability of mentalretarded children of taxonomic category, thematic category and script category.Experiment3focused on children’s ability to classify one item into two categories oftaxonomic and thematic relations simultaneously. Experiment4investigated theability to spontaneously cross-classify items based on taxonomic and thematicrelations.What the results suggested are as follows:(1) In the free association, mental retarded children gave more vocabularies those were of taxonomic or thematic relations with the target words. The words weremost familiar in daily life.(2) When children grew up, the accuracy rate of three category types improved.In addition, the children in age group of10-12and13-15were above chance on threeconcept relations, and we can conclude that they knew the3ways of classification.(3) In accuracy rates,7-12age group children were highest on the category ofthematic relation (77%); while13-15age group were highest on the category oftaxonomic relation (91%). On the scores of classification in three category types,13-15age group were significantly higher than7-9years old children.(4) There were no difference between the scores of different gender and school.(5) Mentally retarded children can classify an item into two categories bytaxonomic and thematic relations at the same time, and at all the items, their accuraterate were above85%. We can conclude that they had the ability to cross-classification.(6) In the selection of conflicting picture, the children showed a classificationbias on taxonomic category.