Manual actions of nine- to fifteen-week-old human infants during face-to-face interaction with their mothers.

This paper presents evidence that the manual actions of infants as young as 9 weeks of age may occur in relation to their facial expression, gaze direction, and vocalization. 28 full-term, healthy infants were observed during a 2-min spontaneous face-to-face interaction with their mothers. Videotapes were coded in real time using the following categories of manual action: POINT, SPREAD, CURL, and GRASP. Facial expressions, gaze direction, and vocalizations also were coded for each infant. All of the infants displayed CURL, 20 infants displayed SPREAD, 18 POINTED, and 11 showed GRASP. Right/left differences appeared for the categories CURL, SPREAD, and GRASP, but not for POINT. Hand action was systematically organized into sequences with other infant action. POINT occurred before or after mouthing and vocalization, CURL during vocalization, and SPREAD when the baby was looking away from the mother. The results are discussed in relation to their implications for the ontogeny of nonverbal communicative gestures.