Results of correlation of analyzed EEG parameters and etiology and time from insult for each patient. Statistically significant correlation are presented on bars plots: occurrence of SS and etiology (p = 0.001**) fig. a), occurrence of SWA and etiology (p = 0.018*) fig. b), occurrence of sleep cycles (p = 0.045*) fig. c), other EEG activity (p = 0.002**) fig. d) and variability of these all activity across time versus etiology (p = 0.02*) fig. e).