Abstract
A recent fMRI study found that the occipital place area (OPA) – a scene-selective cortical region involved in “visually-guided navigation” (i.e., our ability to find our way through the immediately visible environment) – is surprisingly late developing. For example, although OPA responds selectively to scenes by 5 years of age, responses to first-person perspective motion information (mimicking the visual experience of actually navigating a scene) are not present at this age, and rather only emerge by around 8 years of age. Here, we ask why visually-guided navigation may be so late developing, and hypothesize that 5-year-olds, unlike 8-year-olds (and adults), are using visual information from central – not peripheral – vision to navigate through their immediately visible environment. To directly test this hypothesis, we monitored the eye movements of participants (5- and 8-year-olds and adults) while they performed two tasks on the exact same stimuli: i) a “visually-guided navigation” task, in which participants imagined walking along a path on the floor that led only to one of three doors, and indicated (via pointing) whether they could leave through the door on the left, center, or right wall; and ii) a control “scene categorization” task, in which participants imagined standing in a room and indicated (via verbal report) whether the scene was a kitchen, living room, or bedroom. Consistent with our hypothesis, we found that unlike the 8-year-olds (and adults), the 5-year-olds used central – not peripheral – vision during the visually-guided navigation task. By contrast, all groups used central vision during the scene categorization task. These results support the hypothesis of a late developing visually-guided navigation system, and also reveal that the visually-guided navigation system relies on peripheral visual input, while the scene categorization system relies on central visual input.