The book is a collection of Pavlov’s papers written at different times and offering a physiological interpretation of various psychopathological symptoms, syndromes and mental diseases, especially so widespread a disease as schizophrenia. The book also contains Pavlov’s articles which throw light on his teaching on types of nervous' systems and experimental neuroses. These articles are very important for understanding the pathogenesis of various psychogenic disorders, reactive states, neuroses and psychopathias, i.e., problems of so-called borderline psychiatry.Some of Pavlov’s articles published in the present editios deal with various aspects of his physiological teaching on higher nervous activity, particularly his conceptions of inhibition, sleep and hypnosis, with which the reader must familiarise himself to gain a better insight into his point of view on the physiological bases of mental disorders.