He has been examining the emergence of children’s presentational self —the self that emerges from the configuration of a child and others in interaction that creates unique meaning to observers, based on the qualitative analysis of the daily interaction children participate in and the theoretical framework of semiotic mediation. He developed the idea of presentational self from the analysis of mother-child conversations and is trying to apply it to other types of interaction. Another subject of his analysis is the functioning of Gitai-go, a group of mimic words in the Japanese language. Email: komatsu@cc.osaka-kyoiku.ac.jp