Poster #161 - Looking Compensates for Postural Constraints: Infants Center Gaze Targets in View When Looking

• In Event: 2-110 - Poster Session 07
  In Poster Session: PS 07 Section - Perceptual, Sensory, Motor

Integrative Statement

Body posture constrains infants’ visual input. When crawling: infants see more of the floor but sacrifice their view of high and distant locations (Kretch et al., 2014). Looking at faces is also compromised when infants are prone compared with sitting or upright (Franchak et al., 2018). However, those studies only measured the frequency of looking—how often a target was in view and how often it was fixated. Little is known about how posture influences the spatial distribution of gaze targets in infants’ field of view, or how infants’ decisions to look at a target changes its location. Where are targets located in infants’ field of view when infants are in different postures? How do locations change when infants choose to look at the gaze targets compared with not looking?

To answer these questions, this study recorded 12-month-olds’ field of view and eye movements using head-mounted eye trackers while infants freely explored a room. Six toys were provided around the room. Human coders scored infants’ posture from third-person cameras (prone, sitting, or upright; left column of Figure 1) and found the location of target toys in each frame of infants’ field of view videos (white boxes in right column of Figure 1). Eye movement data (green crosses in right column of Figure 1) determined when infants looked at each target toy. The spatial distributions of toy locations in infants’ field of view was determined for each posture to compare when infants looked at each toy (looking episodes) versus when infants were not looking at the toy (non-looking episodes) (Figure 2).

Results showed that toys were located in relatively higher position in infants’ field of view when infants were prone compared with when infants were sitting and upright (Figure 2). However, the spatial structure across postures converged when infants chose to look at toys. Toys became better centered in view during looking episodes across postures in spite of different distributions during non-looking episodes for each posture (white circles in Figure 2 indicate the center of infants’ field of view). These findings suggest that posture affects infants’ visual access to information, specifically the spatial structure of the information in infants’ field of view. However, the differences in visual experiences caused by posture are mitigated by infants’ decision to look at specific gaze targets. While prone, infants were able to center visual information in the view as well as they did in sitting and upright postures during looking episodes. That is, infants’ visual experiences are not passively determined by the frequency of targets appearing in view, which is constrained by posture. Instead, infants actively move their eyes, head, and body to bring information to the center of view when looking.

Authors

• Chuan Luo, University of California Riverside
  Presenting Author

• John Franchak, University of California Riverside
  Non-Presenting Author