[Changes of brain electric activity under general anaesthesia (author's transl)]

The comparison of the influence of HAL, NLA and EHA on the electrical activity of the brain by help of a vigilo-somnogram shows equal directed curves. That is to say that the effect of general anesthesia is to be seen in a inhibition of the central nervous system, from which in the first line the orienting reticular system and pain processing centres of the limbic system are concerned. It has to be emphasized that the sleep-EEG and the EEG of general anaesthesia have a certain similarity but no identity; so the sleep state of the EEG should not be transferred to the anaesthesia states.