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Previous research has shown that 6-month-olds evaluate others on the basis of their social behaviors--they are attracted to prosocial individuals, and avoid antisocial individuals (Hamlin, Wynn & Bloom, 2007). The current studies investigate these capacities prior to 6 months of age. Results from two experiments indicate that even 3-month-old infants evaluate others based on their social behavior towards third parties, and that negative social information is developmentally privileged.
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Hamlin et al. (2010) studied this question.
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