Japan-France-US comparison of infant weaning from mother's viewpoint.

Background: Breastfeeding and weaning are strongly connected with infant-mother mutual autonomy, and hence are good touchstones to examine the characteristics of the mother-child relationship. Comparison of the weaning practice gives a framework to understand characteristics of the mother-infant relationship. Objective: The purpose of this study was to compare three industrialised countries concerning the relationship between feeding and weaning practices and its reasons, mother's perception of child care, and of breast milk and formula. Methods: A questionnaire study on weaning practice was conducted for 310 Japanese, 756 French, and 222 American mothers with 4- to 20-month-old infants. Results: French mothers expected and had accomplished weaning at an earlier age of the infant, compared to Japanese and American mothers. Perceived insufficiency of breast milk was the leading reason for the termination of breastfeeding for Japanese mothers at the earlier stages, whereas back to work was the more important reason for French mothers. Japanese mothers were more negative in their image of themselves as mothers, whereas French mothers felt more burdened by child-care. Japanese mothers who terminated breastfeeding because of perceived breast milk insufficiency were also those who were less motivated to breastfeed. Conclusion: Weaning is a significant framework to interpret cultural differences in mother-infant relationship. The perceived insufficiency is interpreted as a solution of conflict between the social pressure to breastfeed and its burden.

Detection of invariants by haptic touch across age groups: rod length perception.

This study examined the development in the detection of maximum eigenvalues and static moment as invariants, through a task of perceiving rod length without visual information by haptic touch. 34 participants ages 6 to 83 years participated in the experiment. Their exploratory behavior and perceptions of rod length were analyzed by age group (Children: 6 to 12 years old; Young Adult: 21 to 25 years old; Middle Age: 31 to 56 years old; and Older: 65 to 83 years old). A behavior analysis indicated that use of vertical swinging increased for the Young Adult group and decreased with age for the Older group, whereas Children frequently held the rod without wielding. Analysis showed that, by age, differences in coefficients on the maximum eigenvalue and static moment were parallel with an exploratory behavioral change. Finally, the effect of different exploratory behaviors on length perception was discussed.