In the monograph the full interpretation of human brain functioning as an object of electronics is first presented. Three hypotheses are formulated, which on the one hand, enable to explain perception, thinking and other important mental functions and, on the other hand, to propose a perspective combined approach of detailed analysis of the brain, based on multilevel simulation in conjunction with experimental methods. The principles of brain functioning are explained from the point of view of a specialist in electronics. A clear definition of what is the thought is first proposed. The monograph will be of interest to a wide range of readers, including specialists in neurophysiology, neuropsychology, neurocybernetics, electronics, etc., as well as students, as it is written in a clear language without new terms.