Contribution of the visual perception and graphic production systems to the copying of complex geometrical drawings: A developmental study

The aim of this study was to determine the contribution of the visual perception and graphic production systems [Van Sommers, P. (1989). A system for drawing and drawing-related neuropsychology. Cognitive Neuropsychology, 6, 117–164] to the manifestation of the “Centripetal Execution Principle” (CEP), a graphic rule for the copying of drawings consisting of embedded simple geometric shapes from the outside shape to the inside shape. Children aged 4–8 years copied two types of model that differed in the visual salience of one of the simple geometric shapes (drawn in bold or normal weight lines), producing the drawings either by graphic execution (freehand) or by superimposing the simple geometric shapes. The results indicated that the frequency of CEP depended both on the type of model and on the drawing context in the youngest children. They suggest that the CEP is determined by the structure of the representation of the models and the planning of the execution of the drawings. The developmental differences in the effects of visual salience and execution context are discussed in the light of the development of representational flexibility and planning abilities. These data are consistent with a dissociation between the visual perception and graphic production systems and account for their interaction.