Decoding Visual Recognition of Objects from EEG Signals based on Attention-Driven Convolutional Neural Network

TL;DR

This study demonstrates that an attention-driven convolutional neural network can effectively decode EEG signals to classify visual object categories and exemplars, showing promise for real-world brain-machine interfaces.

Contribution

The paper introduces an attention-based CNN model that improves EEG classification accuracy for visual stimuli over conventional methods.

Findings

Achieved 50.37% accuracy for 6-class classification

Achieved 26.75% accuracy for 72-class classification

EEG signals can be differentiated based on visual stimuli at the exemplar level

Abstract

The ability to perceive and recognize objects is fundamental for the interaction with the external environment. Studies that investigate them and their relationship with brain activity changes have been increasing due to the possible application in an intuitive brain-machine interface (BMI). In addition, the distinctive patterns when presenting different visual stimuli that make data differentiable enough to be classified have been studied. However, reported classification accuracy still low or employed techniques for obtaining brain signals are impractical to use in real environments. In this study, we aim to decode electroencephalography (EEG) signals depending on the provided visual stimulus. Subjects were presented with 72 photographs belonging to 6 different semantic categories. We classified 6 categories and 72 exemplars according to visual stimuli using EEG signals. In order to achieve a high classification accuracy, we proposed an attention driven convolutional neural network and compared our results with conventional methods used for classifying EEG signals. We reported an accuracy of 50.37% and 26.75% for 6-class and 72-class, respectively. These results statistically outperformed other conventional methods. This was possible because of the application of the attention network using human visual pathways. Our findings showed that EEG signals are possible to differentiate when subjects are presented with visual stimulus of different semantic categories and at an exemplar-level with a high classification accuracy; this demonstrates its viability to be applied it in a real-world BMI.