GROUPED ARRAYS VERSUS OBJECT-BASED REPRESENTATIONS - REPLY TO KRAMER ET-AL (1997)

An important issue in attention research concerns the representational format from which attention selects. S. P. Vecera and M. J. Farah (19 94) presented results that they argued demonstrated attentional select ion from a spatially invariant object representation. In their comment , A. F. Kramer, T. A. Weber, and S. E. Watson (1997) questioned the in terpretation of these results, and they presented evidence consistent with selection from a grouped location-based representation. In this r eply, the author argues that although an absence of spatial, or distan ce, effects may be ambiguous as to whether attention is selecting from an object-based representation or from a location-based representatio n, there an computational considerations that favor object-based selec tion in certain tasks. The author concludes with a discussion of how o bject-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 mu ltiple forms of attentional selection may coexist in the visual system .