The still-face response in newborn, 1.5-, and 3-month-old infants

The present study investigated the still-face response to a female stranger in newborn, 1.5-, and 3-month-old infants. The results revealed that 1.5- and 3-month-olds, but not newborns, reliably decreased their visual attention and positive affect when the interaction partner became unresponsive during the still-face period.