「小児版図形学習検査」の作成と視覚性記憶の発達変化の分析

Development of a "visual figure learning test for children" and analysis of developmental changes in visual memory

　本研究の目的は，未就学児より長期記憶の評価が可能な小児版図形学習検査を作成・実施し，視覚性記憶の発達変化を分析することである．対象は5～8歳の健常発達児54名．手続きは，Reyの聴覚性言語学習検査(RAVLT)の標準的な方法に従い，被検児には単語の代わりに図形を呈示して，描画による自由再生をさせた．刺激図形は5歳児が模写可能な無意味図形を作成し，各図形には採点基準を定めて採点を行った．その結果，再生課題・再認課題ともに，6～7歳にかけて成績に顕著な差がみられた．再生課題では短期記憶，学習効果，長期記憶ともに，6～7歳で顕著な発達変化がみられ，視知覚認知，運動機能，記憶方略の3点の発達が推測された．再認課題では，本検査の方法で図形を正確に再認できるのは7歳以降と推測された．本検査は，未就学児から施行可能で視覚性記憶の多面的な評価に貢献しうると考えられた．

　In this study, an attempt was made to develop a "visual figure learning test for children" which can be administered to children as young as the preschool years.　The test requires memorizing and drawing meaningless figures from memory (free-recall).　It also looks at the learning process to enable evaluation of long-term memory.　When the test was completed, it was administered to a group of children in order to analyze developmental changes in visual memory.　The subjects were 54 children aged 5 to 8 years who are in good health and exhibiting normal development.　The testing procedure was adopted from the Rey Auditory Verbal Learning Test (RAVLT).　The figures were considered "meaningless" as they could not be named readily.　Five year olds could correctly copy the figures.　Several criteria were established to judge the accuracy of the recalled designs.　In both recall and recognition tasks, notable developmental changes were observed between the ages of 6 and 7.　In the recall tasks, the changes could be explained by developmental spurts around the age of seven in visual perception, manual dexterity, and the use of memory-enhancing strategies such as "finger-drawing".　In the recognition tasks, false positive responses decreased significantly at age 7, and significant increase in p［A］, that is the rate of correct recognition, was obtained.　The results of this study suggest that the "visual figure learning test for children" developed here can be used with preschoolers as a valuable assessment of visual memory.