Changes in Perception-Action Tuning Over Long Time Scales: How Children and Adults Perceive and Act on Dynamic Affordances When Crossing Roads

This investigation examined developmental change in how children perceive and act on dynamic affordances when crossing roads on foot. Six-to 14-year-olds and adults crossed roads with continuous cross-traffic in a large-screen, immersive pedestrian simulator. We observed change both in children's gap choices and in their ability to precisely synchronize their movement with the opening of a gap. Younger children were less discriminating than older children and adults, choosing fewer large gaps and more small gaps. Interestingly, 12-year-olds' gap choices were significantly more conservative than those of 6-, 8-, 10-, and 14-year-olds, and adults. Timing of entry behind the lead vehicle in the gap (a key measure of movement coordination) improved steadily with development, reaching adultlike levels by age 14. Coupled with their poorer timing of entry, 6-, 8-, and 10-year-olds' gap choices resulted in significantly less time to spare and more collisions than 14-year-olds and adults. Time to spare did not differ between 12-year-olds, 14-year-olds, and adults, indicating that 12-year-olds' more conservative gap choices compensated for their poorer timing of entry. The findings show that children's ability to perceive and act on dynamic affordances undergoes a prolonged period of development, and that older children appear to compensate for their poorer movement timing skills by adjusting their gap decisions to match their crossing actions. Implications for the development of perceptionaction tuning and road-crossing skills are discussed. Public Significance Statement This study shows that children's perception-action skills continue to develop well into early adolescence. When crossing a virtual road with traffic in an immersive pedestrian simulator, children between the ages of 6 and 14 exhibited clear changes in their gap choices and movement timing. Children age 10 and under took more small gaps and fewer large gaps than did older children and adults. Timing of entry into the roadway (a key measure of movement timing) improved steadily with development, reaching adultlike levels by age 14. When exiting the roadway, 6-, 8-, and 10-year-olds had significantly less time to spare and more collisions with cars than 14-year-olds and adults. These findings provide a more complete picture of the development of road-crossing skills, and show that precisely coordinating gap decisions and crossing actions is critical for safe road crossing.