P300-based brain computer interface: Reliability and performance in healty and paralhysed participants

Objective: This study aimed to describe the use of the P300 event-related potential as a control signal in a brain computer interface (BCI) for\ud healthy and paralysed participants.\ud Methods: The experimental device used the P300 wave to control the movement of an object on a graphical interface. Visual stimuli,\ud consisting of four arrows (up, right, down, left) were randomly presented in peripheral positions on the screen. Participants were instructed to\ud recognize only the arrow indicating a specific direction for an object to move.\ud P300 epochs, synchronized with the stimulus, were analyzed on-line via Independent Component Analysis (ICA) with subsequent feature\ud extraction and classification by using a neural network.\ud Results: We tested the reliability and the performance of the system in real-time. The system needed a short training period to allow task\ud completion and reached good performance. Nonetheless, severely impaired patients had lower performance than healthy participants.\ud Conclusions: The proposed system is effective for use with healthy participants, whereas further research is needed before it can be used with\ud locked-in syndrome patients.\ud Significance: The P300-based BCI described can reliably control, in ‘real time’, the motion of a cursor on a graphical interface, and no timeconsuming\ud training is needed in order to test possible applications for motor-impaired patients