Percentage of C57BL/6J mice expressing spontaneous seizures during the long-term video-EEG recording period in mice previously exposed to eight repeated flurothyl-induced generalized seizures (flurothyl concentrations, 10% and 100%). Comparisons were made within weeks using Fisher exact tests for the percentage of flurothyl-exposed and control mice having spontaneous seizures. Significant differences (*) were found between flurothyl-exposed and control mice for week 1 (p < 0.00001), week 2 (p < 0.00001), week 3 (p < 0.0003), week 4 (p < 0.03), and week 6 (p < 0.0005). The x-axis represents the duration of the recording period by weeks, whereas the y-axis represents the percentage of mice having SSEs.