Unraveling motor imagery brain patterns using explainable artificial intelligence based on Shapley values.

Journal: Computer methods and programs in biomedicine
Published Date:

Abstract

BACKGROUND AND OBJECTIVE: Motor imagery (MI) based brain-computer interfaces (BCIs) are widely used in rehabilitation due to the close relationship that exists between MI and motor execution (ME). However, the underlying brain mechanisms of MI remain not well understood. Most MI-BCIs use the sensorimotor rhythms elicited in the primary motor cortex (M1) and somatosensory cortex (S1), which consist of an event-related desynchronization followed by an event-related synchronization. Consequently, this has resulted in systems that only record signals around M1 and S1. However, MI could involve a more complex network including sensory, association, and motor areas. In this study, we hypothesize that the superior accuracies achieved by new deep learning (DL) models applied to MI decoding rely on focusing on a broader MI activation of the brain. Parallel to the success of DL, the field of explainable artificial intelligence (XAI) has seen continuous development to provide explanations for DL networks success. The goal of this study is to use XAI in combination with DL to extract information about MI brain activation patterns from non-invasive electroencephalography (EEG) signals.

Authors

  • Sergio Perez-Velasco
  • Diego Marcos-Martinez
  • Eduardo Santamaria-Vazquez
  • Victor Martinez-Cagigal
  • Selene Moreno-Calderón
    Biomedical Engineering Group, E.T.S Ingenieros de Telecomunicación, University of Valladolid, Paseo de Belén 15, Valladolid, 47011, Spain.
  • Roberto Hornero
    Biomedical Engineering Group, University of Valladolid, Valladolid, Spain.