The present study examines the balance between top-down search induced by the expectations of the road user and data-driven search induced by the properties of the visual scene. While viewing video recordings of intersection approaches, subjects searched for a blue traffic sign which was embedded in the intersection scene. Given the layout of the particular scene, the target sign could be located at an expected or an unexpected location within this scene. Dependent on the condition, another traffic sign or another traffic sign and crossing pedestrian were present in the scene. The results reveal the importance of top-down induced search in natural traffic scenes: eye movements were first directed to those locations where target objects were likely to be found. The importance of the role of expectations inducing strategic search was strengthened by the finding that the presence of a distracting sign and a pedestrian hardly altered this search pattern. (A)
Abstract