Zhou Yajun, Hu Li, Yu Tianyou, Li Yuanqing
Center for Brain Computer Interfaces and Brain Information Processing, South China University of Technology, Guangzhou, China.
Guangzhou Key Laboratory of Brain Computer Interaction and Application, Guangzhou, China.
Front Neurosci. 2021 Dec 14;15:746146. doi: 10.3389/fnins.2021.746146. eCollection 2021.
Covert attention aids us in monitoring the environment and optimizing performance in visual tasks. Past behavioral studies have shown that covert attention can enhance spatial resolution. However, electroencephalography (EEG) activity related to neural processing between central and peripheral vision has not been systematically investigated. Here, we conducted an EEG study with 25 subjects who performed covert attentional tasks at different retinal eccentricities ranging from 0.75° to 13.90°, as well as tasks involving overt attention and no attention. EEG signals were recorded with a single stimulus frequency to evoke steady-state visual evoked potentials (SSVEPs) for attention evaluation. We found that the SSVEP response in fixating at the attended location was generally negatively correlated with stimulus eccentricity as characterized by Euclidean distance or horizontal and vertical distance. Moreover, more pronounced characteristics of SSVEP analysis were also acquired in overt attention than in covert attention. Furthermore, offline classification of overt attention, covert attention, and no attention yielded an average accuracy of 91.42%. This work contributes to our understanding of the SSVEP representation of attention in humans and may also lead to brain-computer interfaces (BCIs) that allow people to communicate with choices simply by shifting their attention to them.
内隐注意有助于我们监测环境并优化视觉任务的表现。过去的行为研究表明，内隐注意可以提高空间分辨率。然而，与中央视觉和周边视觉之间神经处理相关的脑电图（EEG）活动尚未得到系统研究。在此，我们对25名受试者进行了一项脑电图研究，他们在从0.75°到13.90°的不同视网膜离心率下执行内隐注意任务，以及涉及外显注意和无注意的任务。以单一刺激频率记录脑电图信号，以诱发稳态视觉诱发电位（SSVEP）用于注意评估。我们发现，以欧几里得距离或水平和垂直距离为特征，在注视被注意位置时的SSVEP反应通常与刺激离心率呈负相关。此外，外显注意比内隐注意获得了更明显的SSVEP分析特征。此外，外显注意、内隐注意和无注意的离线分类平均准确率为91.42%。这项工作有助于我们理解人类注意的SSVEP表现，也可能导致脑机接口（BCI），使人们能够通过将注意力转移到选择上来进行交流。
