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arXiv · 2312.00484

MultiView Independent Component Analysis with Delays

Ambroise Heurtebise·Pierre Ablin·Alexandre Gramfort
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Abstract

Linear Independent Component Analysis (ICA) is a blind source separation technique that has been used in various domains to identify independent latent sources from observed signals. In order to obtain a higher signal-to-noise ratio, the presence of multiple views of the same sources can be used. In this work, we present MultiView Independent Component Analysis with Delays (MVICAD). This algorithm builds on the MultiView ICA model by allowing sources to be delayed versions of some shared sources: sources are shared across views up to some unknown latencies that are view- and source-specific. Using simulations, we demonstrate that MVICAD leads to better unmixing of the sources. Moreover, as ICA is often used in neuroscience, we show that latencies are age-related when applied to Cam-CAN, a large-scale magnetoencephalography (MEG) dataset. These results demonstrate that the MVICAD model can reveal rich effects on neural signals without human supervision.

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Ambroise Heurtebise, Pierre Ablin, Alexandre Gramfort. 2023-12-01. MultiView Independent Component Analysis with Delays. https://arxiv.org/abs/2312.00484

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