Abstract
Shortly after learning to crawl or walk, toddlers successfully use vision to guide navigation through the local visual space. How does this ability develop? One hypothesis is that the emergence of navigational affordance perception depends on active navigation experience (e.g., crawling). However, this hypothesis has never been tested, as almost all prior work conflates perception of navigational affordances with the integration of this information into a motor plan. Here we developed a measure of navigational affordance perception based only on preferential looking. Infants and toddlers viewed 10s videos depicting an egocentric perspective of navigation toward the corner of a room, with one wall containing an open doorway affording further navigation, and the other containing a perceptually similar distractor. Across three experiments, 16-month-old toddlers looked significantly more toward doorways (i) relative to textured, rectangular “paintings” (Experiment 1, N=33), (ii) relative to inverted doorways, strictly controlling for low-level visual features (Experiment 2, N=33), and (iii) regardless of whether the video depicted forward vs. backward ego-motion (Experiment 3, N=36). These results validate our paradigm, and show that 16-mo toddlers, who know how to walk, perceive navigational affordances as salient. Next, to test how navigational affordance perception develops, we compared the toddlers (from Experiment 1) to a group of younger pre-crawling infants (5-month-old, N=33). Unlike toddlers, precrawling infants did not look toward doorways more than paintings. Instead, precrawlers looked toward whichever texture had higher contrast and spatial frequency, regardless of whether it was a doorway or a painting. These results suggest that infant attention to navigational affordances develops during a period of significant change in active navigational experience, sometime between 5 and 16 months. Ongoing work is testing the role of active navigational experience directly, by comparing performance on this task in age-matched groups of crawlers and pre-crawlers.