See and be seen: Infant-caregiver social looking during locomotor free play

Abstract

Face-to-face interaction between infants and their caregivers is a mainstay of developmental research. However, common laboratory paradigms for studying dyadic interaction oversimplify the act of looking at the partner's face by seating infants and caregivers face to face in stationary positions. In less constrained conditions when both partners are freely mobile, infants and caregivers must move their heads and bodies to look at each other. We hypothesized that face looking and mutual gaze for each member of the dyad would decrease with increased motor costs of looking. To test this hypothesis, 12-month-old crawling and walking infants and their parents wore head-mounted eye trackers to record eye movements of each member of the dyad during locomotor free play in a large toy-filled playroom. Findings revealed that increased motor costs decreased face looking and mutual gaze: Each partner looked less at the other's face when their own posture or the other's posture required more motor effort to gain visual access to the other's face. Caregivers mirrored infants' posture by spending more time down on the ground when infants were prone, perhaps to facilitate face looking. Infants looked more at toys than at their caregiver's face, but caregivers looked at their infant's face and at toys in equal amounts. Furthermore, infants looked less at toys and faces compared to studies that used stationary tasks, suggesting that the attentional demands differ in an unconstrained locomotor task. Taken together, findings indicate that ever-changing motor constraints affect real-life social looking.

Figure 1

Schematic drawings of infant and caregiver field of view. Infants (blue) are displayed in (A) prone, (B), upright, and (C) sitting postures. Caregivers (red) are displayed in upright and down postures. Down includes both crouching and sitting as shown in (A). Infant head angles approximate the ranges reported by Kretch and colleagues (2014) for each posture. Caregiver head angles are fixed to a constant downward angle for the sake of illustration.

Figure 2

Simultaneous eye tracking of infant and caregiver. Third-person view (bottom panel) shows infant and caregiver playing while wearing head-mounted eye trackers. Eye trackers captured the first-person views of infant (top left) and caregiver (top right). White cross-hairs indicate each observer’s point of gaze. White circles show the cursor (4º radius) used by coders to determine when infants and caregivers looked at toys and faces.

Figure 3

Face looking (A) and body looking (B) according to infant posture, and face looking (C) and body looking (D) according to caregiver posture. Data are collapsed across locomotor status. Error bars show 1 SE.

Figure 4

Percent of time that (A) infants and (B) caregiver spent in different postures. Data are divided according to infants’ locomotor status. Error bars show 1 SE.

Figure 5

Percent of time that infants and caregivers looked at each others’ faces compared to toys. Error bars show 1 SE.