Abstract
Crossmodal facilitation has been an emerging area in visual spatial perception in recent years. While there has been much research into the visual effects on sound localization (e.g ventriloquist effect), relatively little is known about how sound can influence visual spatial perception. Moreover, very little is known about how sounds can influence attentional deployment a visual search task. Here we investigated whether characteristic and/or spatially congruent sounds can affect visual search performance in a complex visual scene. In Experiment 1a, participants were asked to indicate the presence or absence of a visual target in a complex visual scene. In this experiment, the sound could be spatially congruent or incongruent but the sound was always semantically relevant to the visual target. Results showed a significant benefit for spatially congruent sound when targets were relatively small and appeared in peripheral vision. In Experiment 1b, we varied the number of visual targets (6) and manipulated both the spatial congruency and the characteristic relevance of a sound. In both experiments, we found that sound significantly affected visual search performance (even though participants were instructed to ignore the sound) but characteristic sound had a greater effect on visual search performance than spatial congruency. However, when the target was more difficult to locate, spatially congruent sounds benefitted performance. Our findings suggest that characteristic and spatially congruent sound can affect visual search performance and have important implications for our understanding of multisensory influences on target detection in realistic visual scenes.
Science Foundation Ireland.