The role of multisensory integration and attention in sexual incentive salience

To become sexually aroused and eventually engage in sexual behavior, a sexual incentive must first capture our attention. A mechanism that can enhance the salience of such stimulus is multisensory integration (MSI), where input from different sensory modalities (e.g., visual, auditory, and tactile) that occurs close in time is integrated to form a single multimodal percept. Our main objective was to test whether the salience of sexual images would be enhanced by the simultaneous presentation of (task-irrelevant) sexual audio. Sixty-one heterosexual males took part in a modified attentional blink (AB) paradigm. They were instructed to detect the rotation of two target images (T1 and T2) amongst a rapid series of 17 images, presented for 100 ms each. T1 could show a nude (rated as highly erotic) or a dressed female (rated as neutral), whereas T2 displayed a control image (random animal). T1 and T2 were separated by a single (Lag-2) or seven (Lag-8) filler images. To investigate MSI, we added a task-irrelevant auditory stimulus (1,000 ms) that was always concurrently presented with T1 and either erotic (climatic female voice) or neutral (pseudo-words). Our data show that sexual images induced a larger AB than non-sexual images. However, we found no main effect of audio (sexual vs. non-sexual) on target detection, but a complex interaction between lag, T1 type, and audio type. For Lag-8, the sexual image-sexual audio combination resulted in the lowest target detection. For Lag-2, whenever the image was sexual, there was a substantially larger AB, regardless of the audio. In other words, our results indicate a possible MSI effect for Lag-8 but not for Lag-2. Thus, our study provides the first evidence that MSI modulates the salience of sexual stimuli. Interestingly, sexual MSI seems to require additional processing time or attentional resources before it can have an effect. There are no conflicts of interest.