Grouped arrays versus object-based representations: Reply to Kramer et al. (1997).

Abstract

An important issue in attention research concerns the representational format from which attention selects. S. P. Vecera and M. J. Farah (1994) presented results that they argued demonstrated attentional selection from a spatially invariant object representation. In their comment, A. F. Kramer, T. A. Weber, and S. E. Watson (1997) questioned the interpretation of these results, and they presented evidence consistent with selection from a grouped location-based representation. In this reply, the author argues that although an absence of spatial, or distance, effects may be ambiguous as to whether attention is selecting from an object-based representation or from a location-based representation, there are computational considerations that favor object-based selection in certain tasks. The author concludes with a discussion of how object-based and location-based representations might interact with one another, thereby providing a possible explanation of Kramer et al.'s (1997) results. Such an account may lead to an understanding of how multiple forms of attentional selection may coexist in the visual system.