Zhao Yawei, Tang Jiabei, Cao Yong, Jiao Xuejun, Xu Minpeng, Zhou Peng, Ming Dong, Qi Hongzhi
Department of Biomedical Engineering, College of Precision Instruments and Optoelectronics Engineering, Tianjin University, Tianjin, China.
National Key Laboratory of Human Factors Engineering, China Astronaut Research and Training Center, Beijing, China.
Front Neurosci. 2018 Feb 15;12:79. doi: 10.3389/fnins.2018.00079. eCollection 2018.
Brain-computer interfaces (BCIs), independent of the brain's normal output pathways, are attracting an increasing amount of attention as devices that extract neural information. As a typical type of BCI system, the steady-state visual evoked potential (SSVEP)-based BCIs possess a high signal-to-noise ratio and information transfer rate. However, the current high speed SSVEP-BCIs were implemented with subjects concentrating on stimuli, and intentionally avoided additional tasks as distractors. This paper aimed to investigate how a distracting simultaneous task, a verbal n-back task with different mental workload, would affect the performance of SSVEP-BCI. The results from fifteen subjects revealed that the recognition accuracy of SSVEP-BCI was significantly impaired by the distracting task, especially under a high mental workload. The average classification accuracy across all subjects dropped by 8.67% at most from 1- to 4-back, and there was a significant negative correlation (maximum = -0.48, < 0.001) between accuracy and subjective mental workload evaluation of the distracting task. This study suggests a potential hindrance for the SSVEP-BCI daily use, and then improvements should be investigated in the future studies.
脑机接口（BCIs）独立于大脑的正常输出通路，作为提取神经信息的设备正受到越来越多的关注。作为一种典型的脑机接口系统，基于稳态视觉诱发电位（SSVEP）的脑机接口具有高信噪比和信息传输率。然而，当前的高速SSVEP脑机接口是在受试者专注于刺激的情况下实现的，并且有意避免将额外任务作为干扰因素。本文旨在研究一项具有干扰性的同时进行的任务，即具有不同心理负荷的言语n-back任务，将如何影响SSVEP脑机接口的性能。15名受试者的结果表明，干扰任务会显著损害SSVEP脑机接口的识别准确率，尤其是在高心理负荷下。所有受试者的平均分类准确率从1-back到4-back最多下降了8.67%，并且干扰任务的准确率与主观心理负荷评估之间存在显著的负相关（最大值 = -0.48，<0.001）。本研究表明了SSVEP脑机接口在日常使用中存在潜在障碍，未来的研究应探索改进方法。
