Background. The paper presents an innovative quantitative method for assessing neuropsychic fatigue based on the entropy approach. The relevance of the work is connected with the need to determine the neuropsychic state and resistance to stress in different conditions of human activity. This approach is consistent with the trends of modern psychology research on self-organization in the aspect of identifying the processes that underly the stress response during overcoming physical and central fatigue. The proposed method includes the formula of conditional deterministic entropy, tools of nonequilibrium thermodynamics in its information interpretation (I. Prigogine’s theorem on the minimum of entropy production).

Objective. The approbation results of the criterion estimates of neuropsychic stability for the prediction of motor-motor capabilities, behaviour and state of the individual are shown.

Background. The study of students and athletes (71 boys and 72 girls, average age -20- + 3 years) was conducted based on the data provided by the Biological Faculty of Moscow Lomonosow State University. The approbation of the method carried out on the basis of the data of psycho-physiological indicators (tapping test) allowed to assess the stability of the neuropsychic state of athletes. Results. The data confirmed the validity of the method and made it possible to identify stable and unstable states associated with the growth of neuropsychic stress that may result in central fatigue.

Conclusion. The regularities revealed in the experimental samples do not only correspond to the data of the tapping test technique, but also show more accurate and qualitatively meaningful assessments of the neuropsychic stress and the state of the system as a whole. The approach makes it possible to create a device for monitoring neuropsychic stress, i.e. «Halter tapping», and also allows to make similar assessments of sports teams in the process of training, for example, for game sports.