Kaufmann Tobias, Völker Stefan, Gunesch Laura, Kübler Andrea
Department for Psychology I, Institute for Psychology, University of Würzburg Würzburg, Germany.
Front Neurosci. 2012 May 23;6:72. doi: 10.3389/fnins.2012.00072. eCollection 2012.
Brain-computer interfaces (BCI) based on event-related potentials (ERP) allow for selection of characters from a visually presented character-matrix and thus provide a communication channel for users with neurodegenerative disease. Although they have been topic of research for more than 20 years and were multiply proven to be a reliable communication method, BCIs are almost exclusively used in experimental settings, handled by qualified experts. This study investigates if ERP-BCIs can be handled independently by laymen without expert support, which is inevitable for establishing BCIs in end-user's daily life situations. Furthermore we compared the classic character-by-character text entry against a predictive text entry (PTE) that directly incorporates predictive text into the character-matrix. N = 19 BCI novices handled a user-centered ERP-BCI application on their own without expert support. The software individually adjusted classifier weights and control parameters in the background, invisible to the user (auto-calibration). All participants were able to operate the software on their own and to twice correctly spell a sentence with the auto-calibrated classifier (once with PTE, once without). Our PTE increased spelling speed and, importantly, did not reduce accuracy. In sum, this study demonstrates feasibility of auto-calibrating ERP-BCI use, independently by laymen and the strong benefit of integrating predictive text directly into the character-matrix.
基于事件相关电位（ERP）的脑机接口（BCI）能够从视觉呈现的字符矩阵中选择字符，从而为神经退行性疾病患者提供一种交流渠道。尽管它们已经成为20多年来的研究课题，并且多次被证明是一种可靠的交流方法，但BCI几乎只在实验环境中使用，由专业人员操作。本研究调查了ERP-BCI是否可以在没有专家支持的情况下由非专业人员独立操作，这对于在最终用户的日常生活场景中建立BCI来说是必不可少的。此外，我们将传统的逐字符文本输入与直接将预测文本纳入字符矩阵的预测文本输入（PTE）进行了比较。19名BCI新手在没有专家支持的情况下自行操作了一个以用户为中心的ERP-BCI应用程序。该软件在后台自动调整分类器权重和控制参数，用户不可见（自动校准）。所有参与者都能够自行操作该软件，并使用自动校准的分类器两次正确拼写一个句子（一次使用PTE，一次不使用）。我们的PTE提高了拼写速度，重要的是，没有降低准确性。总之，本研究证明了非专业人员独立自动校准使用ERP-BCI的可行性，以及直接将预测文本集成到字符矩阵中的显著优势。
