Gaze patterns in navigation: encoding information in large-scale environments.

We investigated the role of gaze in encoding of object landmarks in navigation. Gaze behavior was measured while participants learnt to navigate in a virtual large-scale environment in order to understand the sampling strategies subjects use to select visual information during navigation. The results showed a consistent sampling pattern. Participants preferentially directed gaze at a subset of the available object landmarks with a preference for object landmarks at the end of hallways and T-junctions. In a subsequent test of knowledge of the environment, we removed landmarks depending on how frequently they had been viewed. Removal of infrequently viewed landmarks had little effect on performance, whereas removal of the most viewed landmarks impaired performance substantially. Thus, gaze location during learning reveals the information that is selectively encoded, and landmarks at choice points are selected in preference to less informative landmarks.