Early temperament and stranger wariness as predictors of social inhibition in 2-year-olds

Forty-five infants were followed from age 5 months to 25 months with the aim of studying the stranger wariness phenomenon from a temperamental perspective. Observations and heart rate reactions in a standardized situation of stranger approach, as well as maternal ratings of temperament at infant age 5 months and 10 months, were used for predicting inhibition in social situations at 25 months of age. Stranger wariness as reflected in heart rate measures at 10 months proved to be predictive of social inhibition in toddlerhood and both wariness ar 10 months and social inhibition at 25 months were found to be related positively to reactivity to sensory stimulation and negatively to frustration at age 10 months. It was suggested that stranger wariness during the first year of life reflects individual dispositions to respond with withdrawal in response to social novelty and that there are common temperamental underpinnings, such as reactivity to sensory stimulation and to frustration, to both stranger wariness at age 10 months and social inhibition in toddlerhood.