Title: Decoding fNIRS based imagined movements associated with speed and force for a brain-computer interface

Authors: Xinglong Geng; Zehan Li

Addresses: Department of Computer Engineering, Hebei Software Institute, Baoding, Hebei, 071030, China ' School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China

Abstract: Functional near-infrared spectroscopy (fNIRS) is an emerging non-invasive technology applied in brain-computer interface (BCI). This study investigates fNIRS based imagined hand-clenching tasks, indicating that the combinations of speed and force have distinct patterns which can be decoded to develop a BCI system. Twelve healthy participants are instructed to perform imagined left or right hand-clenching tasks; oxy-hemoglobin (HbO2) and deoxy-hemoglobin (Hb) concentrations are acquired from motor cortex using a multi-channel fNIRS system. Feature selection method based on mutual information is employed to select the optimal features for classification, and support vector machine (SVM) is used as a classifier resulting in average accuracies of 84.9% and 86.1% for classifying left and right imagined movements. Compared with traditional fNIRS-BCI system, this study provides a possibility to generate a new control pattern for brain-controlled robots, e.g., speed or force control. There is a potential application to combine fNIRS-BCI system with exoskeleton for rehabilitation.

Keywords: BCI; brain-computer interface; hand clenching; SVM; support vector machine; fNIRS; functional near-infrared spectroscopy; multiple channel; oxy-hemoglobin; speed and force control; exoskeleton; brain-controlled robot; rehabilitation.

DOI: 10.1504/IJMIC.2020.112292

International Journal of Modelling, Identification and Control, 2020 Vol.34 No.4, pp.359 - 365

Received: 10 Dec 2019
Accepted: 24 Mar 2020

Published online: 07 Jan 2021 *

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