Improving motor imagery BCI with user response to feedback
Improving motor imagery BCI with user response to feedback
复制标题
DOI：
10.1080/2326263x.2017.1303253
复制
发表时间：
2017-01-01
影响因子：
2.1
通讯作者：
de Sa, Virginia R.
中科院分区：
文献类型：
--
作者：
Mousavi, Mahta;Koerner, Adam S.;de Sa, Virginia R.
在脑机接口（BCI）系统中，脑信号的非平稳性是训练鲁棒分类器的一个挑战，因为其他脑过程产生的信号与所需脑活动产生的信号一致。一个干扰源是用户对所提供的BCI反馈的认知响应。在运动想象范例的情况下，该反馈可以例如是在屏幕上移动的光标。对这种反馈的响应一般被证明是噪声源，可以增加大脑信号的非平稳性;然而，在这项工作中，我们表明用户对这种反馈的大脑响应可以用于提高BCI性能。我们首先在运动想象任务中显示，用户的大脑响应光标移动的方向，这对于光标朝向或远离目标移动是不同的（即BCI反馈），并且这种反馈相关的信息存在于与运动想象中使用的频带类似的频带中。接下来，我们提出了一个分类器，结合用户的反馈与运动想象信号本身的反应，并表明这种组合分类器可以显着优于传统的运动想象分类器。我们的研究结果显示，10名参与者的分类准确率平均提高了11%，最高可达22%。
In brain-computer interface (BCI) systems, the non-stationarity of brain signals is known to be a challenge for training robust classifiers as other brain processes produce signals that coincide with those resulting from the desired brain activity. One source of interference is the user's cognitive response to the provided BCI feedback. In the case of motor imagery paradigms, this feedback can for instance be a cursor moving on the screen. The response to such feedback has been shown in general to be a source of noise that can add to the non-stationarity of the brain signal; however, in this work, we show that the user's brain response to this feedback can be used to improve the BCI performance. We first show in a motor imagery task that the user's brain responds to the direction of cursor movement, which is different for the cursor moving towards or away from the target (i.e. BCI feedback), and this feedback-related information is present in frequency bands similar to those used in motor imagery. Next, we propose a classifier that combines the user response to feedback together with the motor imagery signal itself, and show that this combined classifier can significantly outperform a conventional motor imagery classifier. Our results show an average of 11% and up to 22% improvement in classification accuracy across 10 participants.