Classification of EEG signals related to real and imagery knee movements using deep learning for brain computer interfaces

Abstract

BACKGROUND:

Non-invasive Brain-Computer Interface (BCI) uses an electroencephalogram (EEG) to obtain information on brain neural activity. Because EEG can be contaminated by various artifacts during the collection process, it has primarily evolved into motor imagery (MI) with a low risk of contamination. However, MI has a disadvantage in that accurate data is difficult to obtain.

OBJECTIVE:

The goal of this study was to determine which motor imagery and movement execution (ME) of the knee has the best classification performance.

METHODS:

Ten subjects were selected to provide MI and ME data for four different types of knee exercise. The experiment was conducted to keep the left, right, and both knees extend or bend for five seconds, and there was a five seconds break between each movement. Each motion was performed 20 times and the MI was carried out in the same protocol. Motions were classified through a modified model of the Lenet-5 of CNN (Convolution Neural Network).

RESULTS:

The deep learning data was classified, and a study discovered that ME (98.91%) could be classified significantly more accurately than MI (98.37%) ( $p<$ 0.001).

CONCLUSION:

If future studies on other body movements are conducted, we anticipate that BCI can be further developed to be more accurate. And such advancements in BCI can be used to facilitate the patient’s communication by analyzing the user’s movement intention. These results can also be used for various controls such as robots using a combination of MI and ME.