Number of averaged EEG trials.

Number of EEG trials per condition and observer group (SD = standard deviation) that entered ERP averaging. Cb: checkerboard; Freq: frequent Cbs.纳入事件相关电位 (Event-Related Potential, ERP) 平均分析的各实验条件及观察者组的脑电 (Electroencephalogram, EEG) 试次数量（SD = 标准差 (standard deviation)）。Cb：棋盘格刺激 (checkerboard)；Freq：高频棋盘格刺激 (frequent Cbs)。