Event-related potentials (ERP) and contingent negative variation (CNV) of the electroencephalogram (EEG) could investigate the responses of concentration and. This study designed two kinds of different interval Stimulation experiments: a short stimulation interval experiment and a long stimulation interval experiment. In the Short stimulation interval experiment, the intervals were 500 ms, 600 ms, 700 ms, 800 ms, 900 ms, and 1s, respectively. In the long stimulation interval experiment, they were 2.2s, 2.4s, 2.5s, 2.6s, 2.8s and 3s, respectively. The experimental results Show that the time interval is Shorter, the amplitude of the CNV is larger, and the concentration of the Subjects is higher. The time interval is longer, the amplitude of the CNV is Smaller and the concentration of the Subjects is lower.