Final Report Summary - MIA (Multisensory Integration and Attention) The beneficial consequences of perceiving and integrating information across different sensory systems have been profusely described in recent literature. For example, we often find it easier to hear someone talking at a noisy party when we can see their face or, can orient more accurately to the blare of an ambulance siren if we can also see its flashing light amongst other cars on the road. This unity of perceptual experience and action is granted through the brain processes of multisensory integration (MSI), which involve converging inputs from different sensory modalities and support their interaction. Multisensory phenomena illustrating this sensory unity have been extensively studied in the laboratory, but often under simplified conditions, where attention can be easily focused on the relevant stimuli. However, these focused attention conditions in the laboratory are very different from most everyday life environments, like the ones illustrated above, where many relevant and irrelevant sensory events can co-occur within a short time window and perhaps at close locations in space. What is more, multisensory coincidences may occur at completely unexpected moments and places. The goal of MIA was to understand the interplay between MSI and attention at a functional level, so that MSI in complex, information-rich, scenarios can be better understood. The starting premise was that attention, and in particular, the interplay between attention and MSI, is critical to achieve a satisfactory account of MSI and therefore, of the unity of perceptual awareness. This idea has brought up challenges, a novel look into some extant controversies, and has illuminated some potentially important new paths.The question addressed, in many of our studies has been, to which extent multisensory integration processes are robust to attentionally compromising situations. The project has garnered evidence from various domains of perception where multisensory integration plays a paramount role: Perception of Space, perception of Time, Body representation, and Speech perception. Our methodologies have ranged from well controlled psychophysical studies using precision or speed of response measures, to brain imaging techniques such as fMRI, ERP or EEG trying to uncover the neural expression of MSI and its modulation by attention at different levels of spatial and temporal resolution. We have also addressed the causal nature of some of these brain correlates, over perception, by using Brain Stimulation techniques, such as TMS.The findings arising from MIA illustrate how, endogenous factors, such as selective attention, can modulate the behavioral and physiological expression of multisensory integration and even its conscious perception. This idea has been echoed by our findings to more or less degree, across all the different domains studies. We have also learned that, besides the influence of selective endogenous attention states, MSI can also be up- or down-regulated by other endogenous sources, such as spontaneous (ongoing) brain states or expectations. Altogether, the final conclusion of the project can be summarized in the idea that multisensory integration in perception cannot be understood without its interplay with attention, and that this interplay may lead to radically different experiences of otherwise similar sensory events.The MIA project has helped strengthen and consolidate multisensory research (and cognitive neuroscience research in general) in our environment, with the graduation of five PhD’s, the transfer of important new skills, and the dissemination of knowledge. In addition, MIA has projected a contribution in the international scene. The results of the studies carried out under the MIA project have led us to publish over 40 papers in scientific journals and books, more than 100 presentations in conferences, feature on public media. Finally, some of the new avenues opened up in MIA are now being the basis for new projects looking into the the applicability of some of the discoveries in the realm of Brain Computer Interfaces (BCI).
