INCC, Université Paris Cité
Traveling Waves in Human Brain
Neural oscillations have been observed across scales, species and recording methods. Recently, researchers have focused on their spatial organization across the cortex. Traveling Waves patterns, specifically, correspond to monotonic phase shifts in the direction of signal propagation and appear to play a role in cognitive functions. Identifying spatio-temporally consistent patterns, however, in non-invasively obtained human data (EEG or MEG recordings) poses significant technical challenges, such as source summation, volume conduction, and low signal-to-noise ratios, which complicate the interpretation of cortical activity from surface sensor measurements. In this talk, I will outline a variety of approaches—including psychophysics, computational modeling, and novel time series analysis tools developed by our lab—to address these challenges. Through psychophysics, we have shown that visual percepts can propagate as waves across retinotopic space. Our theoretical work suggests that this effect is driven by cortical propagation within V1. Moreover, using a model-based neuroimaging approach, we demonstrated that the propagation of neural activity within individual cortical regions can be detected in EEG and MEG recordings, overcoming the aforementioned technical issues. In addition, we found that stereotactic EEG can be employed to capture phase dynamics across different brain regions. Lastly, our lab has developed Waves Space, a modular traveling waves simulation and analysis tool. This toolbox implements a range of methods to detect, characterize, and statistically assess traveling waves.
References:
- Grabot L., Merholz G., Winawer J., Heeger D. and Dugué L. (2024) Traveling Waves in the Human Visual Cortex: an MEG-EEG Model-Based Approach. bioRxiv 2024.10.09.617389. https://www.biorxiv.org/content/10.1101/2024.10.09.617389v2
- Alexander D.M. and Dugué L. (2024). The dominance of global phase dynamics in human cortex, from delta to gamma. eLife reviewed preprint https://elifesciences.org/reviewed-preprints/100674
- Fakche C. and Dugué L. (2024). Perceptual cycles travel across the retinotopic space. Journal of Cognitive Neuroscience 36:1, 200-216. https://direct.mit.edu/jocn/article/36/1/200/117925/Perceptual-Cycles-Travel-Across-Retinotopic-Space