Steps towards a continuous visual evoked code modulated Brain Computer Interface

Abstract

This thesis investigated ways to make visual evoked code modulated brain computer interfaces (BCIs) continuous, as this would extend the usage of BCIs. In an o ine experiment two approaches of making the stimuli continuous were tested. The rst method modi ed the sequences digitally; every location got a binary sequence which was a mix of two Gold codes at the left and right. The other approach mixed the colors of the two Gold codes at the edges of the screen. The trials were classi ed based on the activation of either all all location or only the activation of the extreme left and right. The digitally modi ed sequences classi ed with the activation for all locations reached the same accuracy as the control. However, it had a smaller average distance between the target location and the predicted location. This method is thus an improvement of continuous BCIs.