Cross-modal integration during value-driven attentional capture.

A growing body of evidence suggests that reward may be a powerful determinant of attentional selection. To date, the study of value-based attentional capture has been mainly focused on the visual sensory modality. It is yet unknown how reward information is communicated and integrated across the different senses in order to resolve between competing choices during selective attention. Our study investigated the interference produced by an auditory reward-associated distractor when a semantically-related visual target was concurrently presented. We measured both manual and saccadic response times towards a target image (drum or trumpet), while an irrelevant sound (congruent or incongruent instrument) was heard. Each sound was previously associated with either a high or a low reward. We found that manual responses were slowed by a high-reward auditory distractor when sound and image were semantically congruent. A similar effect was observed for saccadic responses, but only for participants aware of the past reward contingencies. Auditory events associated with reward value were thus capable of involuntarily capturing attention in the visual modality. This reward effect can mitigate cross-modal semantic integration and appears to be differentially modulated by awareness for saccadic vs. manual responses. Together, our results extend previous work on value-driven attentional biases in perception by showing that these may operate across sensory modalities and override cross-modal integration for semantically-related stimuli. This study sheds new light on the potential implication of brain regions underlying value-driven attention across sensory modalities.