Jin Jing, Zhang Hanhan, Daly Ian, Wang Xingyu, Cichocki Andrzej
Key Laboratory of Advanced Control and Optimization for Chemical Processes, Ministry of Education, East China University of Science and Technology, Shanghai, People's Republic of China.
J Neural Eng. 2017 Jun;14(3):036001. doi: 10.1088/1741-2552/aa6213. Epub 2017 Feb 22.
Brain-computer interfaces (BCIs) can help patients who have lost control over most muscles but are still conscious and able to communicate or interact with the environment. One of the most popular types of BCI is the P300-based BCI. With this BCI, users are asked to count the number of appearances of target stimuli in an experiment. To date, the majority of visual P300-based BCI systems developed have used the same character or picture as the target for every stimulus presentation, which can bore users. Consequently, users attention may decrease or be negatively affected by adjacent stimuli.
In this study, a new stimulus is presented to increase user concentration. Honeycomb-shaped figures with 1-3 red dots were used as stimuli. The number and the positions of the red dots in the honeycomb-shaped figure were randomly changed during BCI control. The user was asked to count the number of the dots presented in each flash instead of the number of times they flashed. To assess the performance of this new stimulus, another honeycomb-shaped stimulus, without red dots, was used as a control condition.
The results showed that the honeycomb-shaped stimuli with red dots obtained significantly higher classification accuracies and information transfer rates (p < 0.05) compared to the honeycomb-shaped stimulus without red dots.
The results indicate that this proposed method can be a promising approach to improve the performance of the BCI system and can be an efficient method in daily application.
脑机接口（BCIs）可帮助那些对大多数肌肉失去控制但仍有意识且能够与环境进行交流或互动的患者。最流行的脑机接口类型之一是基于P300的脑机接口。使用这种脑机接口时，要求用户在实验中对目标刺激的出现次数进行计数。迄今为止，大多数已开发的基于视觉P300的脑机接口系统在每次刺激呈现时都使用相同的字符或图片作为目标，这可能会使用户感到厌烦。因此，用户的注意力可能会下降，或者受到相邻刺激的负面影响。
在本研究中，提出了一种新的刺激方式以提高用户的注意力。使用带有1至3个红点的蜂窝状图形作为刺激物。在脑机接口控制过程中，蜂窝状图形中红点的数量和位置会随机变化。要求用户对每次闪烁中出现的点的数量进行计数，而不是闪烁的次数。为了评估这种新刺激方式的性能，使用另一种没有红点的蜂窝状刺激物作为对照条件。
结果表明，与没有红点的蜂窝状刺激物相比，带有红点的蜂窝状刺激物获得了显著更高的分类准确率和信息传输率（p < 0.05）。
结果表明，该方法可能是提高脑机接口系统性能的一种有前景的方法，并且在日常应用中可能是一种有效的方法。
