title: Extrinsic rewards undermine altruistic tendencies in 20-month-olds.
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.
authors.affiliation: Department of Developmental and Comparative Psychology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany. warneken@eva.mpg.de
authors.forename: Felix
authors.initials: F
authors.lastname: Warneken
authors.forename: Michael
authors.initials: M
authors.lastname: Tomasello
mesh_terms: D000533:Altruism; D005260:Female; D006379:Helping Behavior; D006801:Humans; D007223:Infant; D007389:Internal-External Control; D008297:Male; D009042:Motivation; D002666:Psychology, Child; D012057:Reinforcement, Verbal; D012201:Reward