The Structure of Visual Spatial Representations

Reference frames are ubiquitous in spatial cognition, and they have been essential in the visual attention literature. Although most studies involving reference frames have been typically designed to examine how a spatial location can be defined in different ways depending on the reference point that is used, they often come to the unsupported conclusion that these constructs have a specific compositional format, the Cartesian coordinate system. The present study designed a modified version of the spatial cueing paradigm to examine the extent to which attention can be guided by encoding locations within compositional (coordinate) spatial representations. Experiment 1 used 75%-valid, compositional word cues that conveyed separate information about the likely direction and distance of the target. The main results showed that these cues elicited a compositional gradient arising from the combined activation of their separate spatial dimensions and were consistent with the use of a Cartesian coordinate reference system. Experiment 2 used non-compositional number cues to rule out an alternative account. Experiment 3 examined the dynamic nature of these compositional gradients over time. And Experiment 4 examined a boundary condition that could potentially limit the emergence of these compositional gradients. These findings were interpreted within a theory of conceptual control that distinguish sitional and can be used to guide attention from one object to another. But conceptual representations depend on non-compositional, perceptual representations to bind the activations arising from their separate spatial dimensions, much like non-spatial feature dimensions do.