The Cross-sectional Research Of Number Processing: In A Life-span Frame

As an extension of previous scopes of development,the life-span perspective focuses on all ages in one's lifetime,investigating the developmental mechanism of one's cognition and behavior. Life-span perspective,which has penetrated into all fields in developmental psychology, has brought new problems and challenges to related areas and managed researchers to concern developments of adults and the aged,as well as children.Focusing on the whole life,the life-span perspective can make us understand those important concepts and principles more clearly and explain them more reasonably.Numerical processing signifies the process in which one receives the numerical stimulus and forms representations of those numbers,applying them to process information (e.g.,magnitude comparison and calculating).To human beings,numerical process is the basic form of thinking,as well as the necessarily basic ability of knowing the world.Under the life-span developmental perspective,present study elaborated several models on numerical process and reviewed previous studies.Based on it,in a cross-sectional way,this study investigated life-span developmental mode of numerical process and the features of different ages within the process.Also,generality of the effects of number magnitude were discussed which had been discussed widely in the domain of numeric process.102 subjects,selected from Shanghai and Taiyuan,were asked to complete tasks of calculation,naming speed,numerical comparison,and calculation(computerized).We got these conclusions:(1)Number processing belonged to the domain of mechanics of cognition in the two-component model on life-span intellectual development proposed by Baltes.Its development showed an obvious inverse U curve,indicating that mechanics of cognition improved as the age grows up,while it decayed from the early period of youth.(2)Under the framework of life-span,effects of number magnitude existed ubiquitously. (3) Subjects performed well in calculation,and there was no significant individual difference.(4) Response latencies in naming speed task and magnitude comparison task increased as difficulties of materials rise.(5) There were significant performance differences in tasks using dice and dots among children,adult,and the aged respectively,indicating that children were more subjective to materials than the middle-aged and the aged,which could be surmised that children's abilities of number processing on dots were relatively poorer.