Abstract
Over the past decade there has been mounting evidence suggesting that attentional allocation is guided by object representations and that attentional prioritization is the mechanism that gives rise to object-based effects. However, it should be noted that most evidence for object-based guidance has been garnered by studies restricted exclusively to the visual modality. As such, it remains unclear whether object-based guidance of attention is unique to the visual modality or, rather, it reflects a general property of attentional allocation. In the present set of experiments we investigated whether cross modal attentional allocation is also object-based. Participants were presented with a visual display consisting of two rectangles that included two cross-modal cue-target combinations. In the first experiment a visual cue was followed by an auditory target presented at the cued location or at an equidistant location on either the same object or a different object. In the second experiment, an auditory cue was presented followed by a visual target. It was observed that in both cross-modal cue-target pairings (audio/visual and visuo/auditory) objects guided attentional allocation such that same-object targets were detected faster than different-object targets. Additional experiments were conducted to examine whether attentional prioritization is the mechanism guiding cross-modal object-based guidance by introducing probabilistic imbalances such that more targets appeared on different-object locations as compared to same-object locations. The observed pattern of results strongly suggests that object-based attentional guidance is not restricted to the visual modality alone but extends to cross-modal attentional orienting, and that attentional prioritization is the mechanism subserving such guidance. Taken together, these results place further constraints on the mechanisms of attentional allocation.