The ontogeny of face identity; I. Eight- to 21-week-old infants use internal and external face features in identity.

A paradigm was designed to study how infants identify live faces. Eight- to 21-week-old infants were seated comfortably and were presented an adult female, dressed in a white laboratory coat and a white turtle neck sweater, until habituation ensued. The adult then left the room.

Changing determinants of crying termination in 6- to 12-week-old human infants.

Developmental change in human infant crying termination was studied in 60 infants who were 6, 9, and 12 weeks of age. They qualified by spontaneously crying for at least 30 s during the study's first minute. Infants then received either 0.