Audiovisual links in endogenous covert spatial attention.

In 7 experiments we investigated cross-modal links for endogenous covert spatial orienting in hearing and vision. Participants judged the elevation (up vs. down) of auditory or visual targets regardless of their laterality or modality. When participants were informed that targets were more likely on 1 side, elevation judgments were faster on that side, even if the modality of the target was uncertain. When participants expected a target on a particular side in just 1 modality, corresponding shifts of covert attention also took place in the other modality, as evidenced by faster elevation judgments on that side. However, it was possible to "split" auditory and visual attention when targets in the 2 modalities were expected on constant but opposite sides throughout a block, although covert orienting effects were larger when targets were expected on the same side in both modalities. These results show that although endogenous covert attention does not operate exclusively within a supramodal system, there are strong spatial links between auditory and visual attention.