Cue modality modulates interaction between exogenous spatial attention and audiovisual integration.

Exogenous spatial attention attenuates audiovisual integration (AVI). Previous studies on the effects of exogenous spatial attention on AVI have focused on the inhibition of return (IOR) effect induced by visual cues and the facilitation effect induced by auditory cues, but the differences between the effects of exogenous spatial attention (induced by visual and auditory cues) on AVI remain unclear. The present study used the exogenous spatial cue-target paradigm and manipulated cue stimulus modality (visual cue, auditory cue) in two experiments (Experiment 1: facilitation effect; Experiment 2: IOR effect) to examine the effects of exogenous spatial attention (evoked by cues in different modalities) on AVI. The results of Experiment 1 showed that the AVI effect at valid cue locations was significantly lower than that at invalid cue locations in both visual and auditory cue conditions, suggesting that the exogenous spatial facilitation effect evoked by both visual and auditory cues attenuated AVI. Further analysis showed that the facilitation effect induced by visual cues attenuated AVI to a greater extent than that induced by auditory cues. In Experiment 2, the AVI effect was significantly lower at valid cue locations than at invalid cue locations in the visual cue condition, whereas there was no significant difference in AVI effect between valid and invalid cue locations in the auditory cue condition, suggesting that the exogenous spatial IOR effect evoked by visual cues attenuated AVI, while the IOR effect evoked by auditory cues had no significant effect on AVI. Taken together, these results may suggest that exogenous spatial attention induced by visual cues has a greater effect on AVI than that induced by auditory cues.