Traveling waves: defining the mechanisms allowing attention to occur in space and in time
Brain oscillations have always fascinated both scientists as well as the general public, but their functional role remains ill defined. My research contributed to addressing this issue, and demonstrated that oscillations modulate attentional performance periodically in time. Oscillations create periodic windows of excitability, with more or less favorable periods recurring at particular phases of the oscillations. However, attention emerges from systems not only operating in time, but also in space. Previous research has emphasized the temporal aspect of brain oscillations’ behavior. Contemporary investigators rarely consider both temporal and spatial dimensions in their search for the mechanisms linking oscillations and attention. This is the challenge I propose to take on. I will address this essential question: How does the spatio-temporal organization of brain oscillations impact attention? I hypothesize that oscillations propagate over the cortical surface, so-called oscillatory Traveling Waves, allowing attentional facilitation to emerge both in space and time. I propose to test this original hypothesis using a model-based multimodal functional neuroimaging approach including non-invasive and invasive recordings in humans. Interventional approaches will additionally be used to evaluate the degree of causality in the relation between traveling waves and attention. This project could lead to major progress in cognitive psychology and neuroscience by bridging the gap between spatial and temporal dynamics underlying multi-sensory experience. An important methodological development is also expected. The model-based multimodal functional neuroimaging approach that I will develop and evaluate on a large set of data will provide a new methodological guide for the study of brain activity.