1. A system (1) of neural feedback, comprising: an electrode (2, 2 ', 2 ") for contact with the skin (6) of the user (7) in order to measure the signal (9) biofeedback of the user (7), the first block ( 3) signal processing to determine the characteristic (11) of the signal of the measured biofeedback signal (9), while the characteristic (11) of the signal represents neural feedback, the second signal processing unit (4) for determining the quality (12) of the biofeedback signal of the measured signal ( 9) biofeedback by highlighting the sign of the signal of the measured signal (9) biofeedback and calculating the probability of a measurement error for the mentioned sign of the signal, the probability representing the quality (12) of the biofeedback signal, as well as the feedback unit (5) for providing feedback to the user, while the feedback contains neural feedback as well as feedback about the quality (12) of the feedback signal, while the feedback intensity is based on the quality (12) of the biofeedback signal. 2. The neural feedback system of claim 1, wherein said electrode (2, 2 ', 2 ") is a dry electrode. 3. The neural feedback system of claim 1, wherein the neural feedback system is a neural feedback system real-time, configured to provide the user with real-time feedback 4. The neural feedback system according to claim 1, in which the measured biofeedback signal (9) is divided into time segments, while the characteristic (11) of the signal and / or quality (12) a biofeedback signal is determined for each time segment independently. 5. The neural feedback system of claim 1, wherein1. Система (1) нейронной обратной связи, содержащая:электрод (2, 2', 2") для контакта с кожей (6) пользователя (7) с целью измерения сигнала (9) биообратной связи пользователя (7),первый блок (3) обработки сигнала для определения характеристики (11) сигнала измеренного сигнала (9) биообратной связи, при этом характеристика (11) сигнала представляет нейронную обратную связь,второй
