Journal Articles

1. Warneken, F; Tomasello, M, Extrinsic rewards undermine altruistic tendencies in 20-month-olds., Developmental psychology, vol. 44 no. 6 (November, 2008), pp. 1785-1788 [doi].
   (last updated on 2026/01/18)

   Abstract:
   The current study investigated the influence of rewards on very young children's helping behavior. After 20-month-old infants received a material reward during a treatment phase, they subsequently were less likely to engage in further helping during a test phase as compared with infants who had previously received social praise or no reward at all. This so-called overjustification effect suggests that even the earliest helping behaviors of young children are intrinsically motivated and that socialization practices involving extrinsic rewards can undermine this tendency.