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The development of stranger fear in infancy and toddlerhood: normative development, individual differences, antecedents, and outcomes

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The development of stranger fear in infancy and toddlerhood: normative development, individual differences, antecedents, and outcomes

Rebecca J. Brooker, Kristin A. Buss, Kathryn Lemery‐Chalfant, Nazan S. Aksan, Richard J. Davidson, H. Hill Goldsmith · 2013 · Developmental Science

Children
About 1,300 twins
Where
Wisconsin, United States
Ages
6 months to 3 years
How
Parents' questionnaires and researchers' observations as children grew
What it found
Wariness of strangers rose on average from 6 to 12 months and then levelled off. Children followed different paths: about 4 in 10 rose steeply, about a third rose slowly, and about 1 in 4 started high.
Limits
It describes how wariness changes, not the age it starts. Mostly white families in one state.

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