Toys are me: children's extension of self to objects.

Adults tend to believe that objects can function as extensions of people's selves. This belief has been demonstrated in that changes to people's sense of self affect their attachment to personally valuable objects, and vice-versa. Here we tested the development of this belief. In Study 1 we found that manipulating 5-year-olds' self-worth via positive or negative feedback on performance, affected their willingness to part with personally valuable objects, but had no effect vis-à-vis non-valuable objects. In Study 2 we found that 9-, but not 5-year-olds were more willing to give a personally valuable object to someone morally repulsive after the object had been cleaned of all remnants of the child's self, than before. Study 2b showed an analogous effect in 5-year-olds' willingness to receive an object from someone morally repulsive. These findings intimate that the extension of self to objects via contagion may derive not only from cultural values such as consumerism, materialism, or individualism, but also from basic human needs.