Under the system of human-machine interaction (we will further designate it by the word “system”), we will understand the totality of three interconnected components: a person (computer user), a computer and an BCI. The BCI includes a software and hardware complex (SHC) and information coming from the brain, most often in the form of electrical signals - electroencephalograms (EEG). The SHC currently operates mainly on the principle of “stimulus - reaction”, the stimulus is a signal coming from the user, in response to it, the software of the SHC provides the generation of a certain reaction. This procedure corresponds to the reactivity paradigm. At the same time, in the vast majority of cases, when the SHC was replaced by a human expert, the interface operation turned out to be more efficient. Therefore, it can be assumed that the use of the paradigm used by experts in the system contributes to improving the results of its work.