Abstract
When spatiotemporal continuity of attended objects is disrupted, object correspondence needs to be established to maintain attentional selection. Spatial configurations are insufficient for establishing object correspondence as demonstrated by impaired multiple object tracking across abrupt scene rotations. The contribution of object features for establishing object correspondence in attentive tracking is unknown. Although object features are poorly retained during attentive tracking when retention is explicitly tested, tracking performance increases if objects stay uniquely colored during movement. We report three experiments examining the impact of briefly shown feature information on maintaining visual spatial attention across spatiotemporal discontinuities elicited by abrupt scene rotations. In Experiment 1, participants tracked 3–5 out of 10 objects in a 3D-scene lasting 6 seconds. In half of the trials we introduced abrupt scene rotations of 30° after 3 seconds. After 2.5 s all objects changed their color for 1000 ms, thus staying colored across scene rotations. Object colors were either unique or homogeneous. Unique object colors improved tracking across abrupt scene rotations. In Experiment 2 and 3, we manipulated whether color information was available to establish correspondence at the abrupt scene rotations. We introduced two 500 ms color intervals, one before and one after the scene rotation. They were separated by 0 ms (replicating the 1000 ms interval in Experiment 1), 500 ms, or 1000 ms to the abrupt scene rotation each. Between color intervals objects were white. The advantage of unique color information was higher when unique colors were present at the time of the scene rotation. When colors were restricted to equidistant gradations of a hue of 153–207 degree in HSV color space (thus preventing verbalization strategies) the feature effect was present with colors at the time of the scene rotation only. We conclude that feature information is used to maintain visual spatial attention across abrupt spatiotemporal discontinuities.
This research was supported by German Research Foundation (DFG) Grants HU 1510/4-1 and JA 1761/5-1.