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A cross-cultural comparison of the development of the social smile
Viktoriya Wörmann, Manfred Holodynski, Joscha Kärtner, Heidi Keller · 2012 · Infant Behavior and Development
- Children
- About 45 babies
- Where
- Münster in Germany, and Nso families in Cameroon
- Ages
- 6 and 12 weeks
- How
- Researchers filmed babies playing with their mothers
- What it found
- At 6 weeks, few babies in either place smiled at their mother during the filmed play. By 12 weeks, 7 in 10 German babies did, against 1 in 4 Nso babies.
- Limits
- Small groups, filmed for a short time; it measured how many babies smiled during the session, not when they first smiled.