EEG were recorded in all subjects under three states: eyes closed, nociceptive stimulus and auditory stimulus.EEG nonlinear indexes of ApEn and cross-ApEn were calculated for all subjects.

• 所有患者依次采集安静闭眼、声音刺激和痛觉刺激三种状态下的脑电信号，并计算脑电信号的近似熵和互近似熵非线性指数。