Gaze-independent visual brain-computer interfaces
One goal of Brain-Computer Interface (BCI) research is to enable paralyzed patients to communicate. For the popular Matrix Speller, recent studies have shown that the spelling accuracy breaks down when the user is not allowed to fixate the target symbol. This observation raises the need for BCI spellers that work effectively for patients with serious oculomotor impairment. Here we will present three visual spellers based on covert spatial attention and non-spatial feature attention. Results with 13 healthy participants demonstrate that these spellers obtain a similar spelling performance during center fixation as the orignal Matrix Speller with target fixation.