research areaHealth, research areaMethods and Algorithmsworkshop Workshop at NeurIPS
content type paperpublished November 2022

MAEEG: Masked Auto-encoder for EEG Representation Learning

AuthorsHsiang-Yun Sherry Chien, Hanlin Goh, Christopher M. Sandino, Joseph Y. Cheng

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This paper was accepted at the Workshop on Learning from Time Series for Health at NeurIPS 2022.

Decoding information from bio-signals such as EEG, using machine learning has been a challenge due to the small data-sets and difficulty to obtain labels. We propose a reconstruction-based self-supervised learning model, the masked auto-encoder for EEG (MAEEG), for learning EEG representations by learning to reconstruct the masked EEG features using a transformer architecture. We found that MAEEG can learn representations that significantly improve sleep stage classification (∼ 5% accuracy increase) when only a small number of labels are given. We also found that input sample lengths and different ways of masking during reconstruction-based SSL pretraining have a huge effect on downstream model performance. Specifically, learning to reconstruct a larger proportion and more concentrated masked signal results in better performance on sleep classifica- tion. Our findings provide insight into how reconstruction-based SSL could help representation learning for EEG.

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