Walking‐Related Changes in Infants' Daily Experiences of Postural Transitions: A Longitudinal Assessment

Postural transitions occur when infants switch from one posture to another, such as from prone to sitting. Postural transitions facilitate perceptual-motor exploration because different postures afford unique learning opportunities. However, extant studies on postural transitions are limited to laboratory play sessions, so it is unknown how frequently transitions occur in daily life. In the present study, we assessed infants' daily experiences with postural transitions. In particular, we tested whether the frequency of transitions and the type of transitions change with infants' increasing walking experience. We developed a novel video-based ecological momentary assessment (vEMA) to longitudinally collect videos of infants' activities throughout the day in their home environment at 11 and 13 months of age. We identified postural transitions in the resulting 3210 video observations collected from N = 44 infants across the United States, which revealed that the frequency and type of transitions differed according to walking experience. The frequency of postural transitions decreased with accumulated walking experience. Infants with greater walking experience more frequently engaged in transitions involving upright postures in their daily lives.