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The Application of Visual Evoked Potentials in Brain-Computer Interface

The article presents the concept of a universal BCI system based on the detection of Steady-State Visual Evoked Potentials (SSVEP). One of the possibilities of its application involves, for example, the visual keyboard which makes it possible to enter data (alphanumeric characters) into the computer without using muscles. The first part discusses the construction and the principle of operation of BCI interfaces and next the most frequently used evoked potentials are presented. An application allowing for an analysis of the EEG signal of a person subject to effect of the photostimulator using stimuli with the frequency ranging from 1 to 40 Hz. As a result of the developed program the appropriate frequency of a stimulus in the EEG signal was detected and signalled.