The development of symmetry concept in preschool children.

Young children are exposed to symmetrical figures frequently before they are taught the concept of symmetry, which is a valuable experience for the development of geometry; however, limited research has explored how this concept develops. This study investigated the developmental sequence of "general symmetry" concept and "specific symmetry" concepts (i.e., bilateral, rotational, and translational symmetry) with 106 4-6-year-old children using a symmetry deviant detection task. The test examined children's conception of general symmetry against asymmetry, specific symmetry against asymmetry, and discrimination of specific symmetries. The results suggested that the concept of symmetry develops as a differentiation process. The concept of general symmetry was acquired first, followed by specific symmetries which were acquired in sequential order.