, Volume 64, Issue 7, pp 1017-1027

Object-based selection within and beyond the focus of spatial attention


In a series of experiments, we examined the effect of perceptual objects on visual attentional processing in the presence of spatially cued attentional selection. Subjects made speeded judgments about two visual elements that were either both on the same object or on two different objects. Judgments were faster when the elements were on the same object than when they were on different objects, revealing an object advantage. Importantly, the object advantage remained even when either exogenous or endogenous spatial cues were used to direct the subjects’ attention to a part of the display, contrary to earlier findings of other researchers. The object advantage, however, did disappear when the stimulus duration was shortened substantially. The results show that object-based selection is pervasive and is not diminished by the act of selective attention. The results are discussed in terms of their implications for the mechanisms that underlie attentional selection.

Portions of the research reported in this article were submitted in partial fulfillment of the requirements for a doctoral degree by M.B.L. The research reported here was supported by Grants MH45145 from the National Institutes of Health and BCS-0079594 from the National Science Foundation.