Townsend George, Graimann Bernhard, Pfurtscheller Gert
Department of Computer Science, Algoma University, Sault Ste. Marie, ON P6A 2G4, Canada.
IEEE Trans Neural Syst Rehabil Eng. 2004 Jun;12(2):258-65. doi: 10.1109/TNSRE.2004.827220.
Nearly all electroencephalogram (EEG)-based brain-computer interface (BCI) systems operate in a cue-paced or synchronous mode. This means that the onset of mental activity (thought) is externally-paced and the EEG has to be analyzed in predefined time windows. In the near future, BCI systems that allow the user to intend a specific mental pattern whenever she/he wishes to produce such patterns will also become important. An asynchronous BCI is characterized by continuous analyzing and classification of EEG data. Therefore, it is important to maximize the hits (true positive rate) during an intended mental task and to minimize the false positive detections in the resting or idling state. EEG data recorded during right/left motor imagery is used to simulate an asynchronous BCI. To optimize the classification results, a refractory period and a dwell time are introduced.
几乎所有基于脑电图（EEG）的脑机接口（BCI）系统都以提示节奏或同步模式运行。这意味着心理活动（思维）的开始是由外部节奏控制的，并且脑电图必须在预定义的时间窗口内进行分析。在不久的将来，允许用户在希望产生特定心理模式时随时有意产生这种模式的脑机接口系统也将变得很重要。异步脑机接口的特点是对脑电图数据进行连续分析和分类。因此，在预期的心理任务中最大化命中次数（真阳性率）并在休息或空闲状态下最小化误报检测非常重要。在右/左运动想象期间记录的脑电图数据用于模拟异步脑机接口。为了优化分类结果，引入了不应期和停留时间。
