[Benzodiazepines and limbic system. Anxiety and vigilance (author's transl)]

A neurophysiological study of 4 benzodiazepines in the free implanted cat serves as basis to a discussion concerning tranquilizers, anxiety and vigilance. The electrophysiological and behavioural effects of diazepam, nitrazepam, lorazepam and of clorazepate dipotassique are analysed and compared between them and other psychotropic drugs. Their mode of action on the behaviour, on the bioelectric cortical and hippocampal rhythms, is explained according to recent biochemical data. The relations with anxiety, vigilance and neuro-psycho-physiologic mechanisms which subtend them are discussed at the light of clinical effects provoked by substances called tranquillizers.