In the course of our work, we often encounter patients who ask: “Does EEG have any effect on the body?” . In fact, EEG is an examination method that has no effect on the body at all. The human tissue cells are always generating weak bioelectric activity spontaneously and continuously. After the patient puts on a cap with electrodes, the electrical activity of brain cells is induced through the electrodes on the cap and amplified by the EEG machine, and the graphs and curves with certain waveforms, amplitudes, frequencies and phases can be obtained on the computer monitor, that is, the EEG. However, when pathological or functional changes occur in brain tissue, this curve will change accordingly, thus providing a basis for clinical diagnosis and treatment. So far, EEG is one of the most important, valuable and convenient means to assist in the diagnosis of epilepsy. Different physiological states of the human body have different EEG waveforms, and people have different EEG performance during wakefulness, stress, sleepiness, and different sleep stages. In clinical practice, many drugs have direct or indirect effects on brain functions, especially those that act directly on the central nervous system, which can cause significant brain wave changes. Routine EEG is usually performed in the awake state to understand the background brain waves and the presence or absence of epileptiform waves, but in children under 5 years of age who cannot cooperate, it must be performed after sleep. The detection rate of routine EEG epileptic waves during interictal seizures is generally around 30% to 50%. It is generally believed that during sleep, especially light sleep, epileptic waves are issued more than twice as often as during wakefulness. This is due to the reduced function of the brain’s reticular upstream activation system during sleep, which makes the cortical and limbic systems out of control and prone to epileptic wave emission, so for some epilepsy prone to seizures during sleep, sleep-induced EEG is particularly suitable. There are three common methods of sleep-induced EEG: natural sleep, sleep deprivation and pharmacological sleep. In general, EEG is performed during the daytime in hospitals, and most people have difficulty falling asleep naturally immediately during the examination, while sleep-inducing drugs may inhibit the release of epileptic waves and mostly produce fast waves, which affect the observation of EEG. Sleep deprivation, i.e., forbidding the subject to sleep, is generally 24 to 48 hours for adults and 5 to 8 hours for children, after which the subject is allowed to fall asleep in a quiet environment and the EEG waves are subsequently traced. For example, children aged 4 to 6 years should get up at 3 to 4 a.m., and their family members should play with them and not let them fall asleep again, and then let them fall asleep when they come to the hospital for examination at 8 to 9 a.m. The specific time of sleep deprivation varies with different ages and physical conditions. Generally, the older the child is, the longer the deprivation time should be, and for those who usually have difficulty sleeping, the deprivation time should also be longer, in order to let the patient fall asleep quickly during the examination.