Sources and impact of human brain potential variability in the brain-computer interface

In the brain-computer interface based on P300 wave (P300 BCI), selection of command by user becomes possible due to focusing user's attention external stimulus/command and extraction response this stimulus in form event-related potential (ERP) components from EEG. To obtain ERP signal, stimuli should be repeated many times, however, view existing variability latency certain stimuli, averaged ERPs may give a distorted nature such responses reduce accuracy interface. The study was aimed develop an effective method for identification effects components' accounting these BCI, as well identify impact psychophysiological factors variability. We have conducted BCI-based 19 healthy subjects involving adjustment N1 spatial components, which play key role classification explore mechanisms underlying Such approach ensured higher compared use conventional EEG leads, highest increase 10% observed when using minimum number repetitions. Furthermore, modifications allowing one ensure level focus task more accurate visual fixation target objects contributed amplitude reducing single stimuli. findings emphasize important processes provide tool scientific exploration development advanced BCI systems.