Abstract :
Summary form only given. The onset of crawling is a dramatic arrival in the parade of infants´ new motor skills. Mahier, Pine, and Bergman (1975) assigned locomotion acquisition is a role in the development of infants´ psychological independence from their caregivers. Despite the potential contributions of locomotion to human development, however, the human infants´ ability to locomote has rarely been treated empirically (Gustafson (1984). Recently, some researchers pointed out the onset of crawling is a vital role in early development and involves a pervasive set of changes in perception, cognition, and social development (Campos et al., (2000). A great deal of effort has been made on relation between crawling onset and perception, cognition development. What seems to be lacking, however, is relation between crawling onset and social development. This derives us to the question why does crawling onset relate to social development. What I wish to show in present study is whether the structure of mother-infant interaction would change as infants started crawling. Mothers and infants (12 pairs) were videotaped to play scene monthly from 6 to 10 months of age (7 boys and 5 girls). None was able to creep or crawl. Observations in the laboratory were scheduled at times that were optimal for baby. Free play scene is videotaped in 10 minutes. All mothers and infants come to laboratory every month. Behavior categories are following: (1) mother-infant physical distance (keep in touch, nearby, faraway): (2) the style of interaction (face-to-face, not face-to-face). These categories were checked by 5 seconds bout. All infants were assessed locomotion ability every month, and were classified in one of three stages. The prelocomotor stage is that infants can´t locomote with oneself alone at all. The creeping stage is that infants can locomote alone with creeping. The crawling stage is that infants can locomote alone with crawling. Coding was done by a graduate student who wa- s naive to the purpose of this study and author. A Cohen´s kappa was used to assess inter-coder reliability. Kappa for behavior categories was 0.92. The following results were obtained: In the prelocomotor stage, structure of mother-infant interaction tended to distance of both were near, but it was not face-to-face. However, the structure changed when infants began to locomote( the creeping stage). In this stage, between mothers and infants come to occur a remote distance, on the other hand, face-to-face interaction increased. In next stage (the crawling stage), furthermore, between mothers and infants come to occur a near distance again but face-to-face situation had been maintained. It is said that locomotion development is a very important for later social cognitive development. However there seems to be no established theory to explain this suggestion. To examine the structural changes of mother-infant interaction on the basis of a point of view of infant´s locomotion ability might offer the key to understanding of dramatic changes of infants´ social cognitive development. Further detailed examination of the findings fostered a number of plausible hypotheses to account for this communality
