Here we provide EEG (electroencephalogram) data recorded during BCI (brain-computer interface) control. The BCI was intended for the decoding of binary decisions from a series of colored laminar stimuli. The decoding task is to determine to which of the simultaneously presented items the participant shifted his/her attention. By determining the visual field a subject's attention was shifted to, the intended target color can be determined. 14 participants were presented with 144 sequences of ten visual stimuli in which a red and a green surface was simultaneously illuminated in opposite visual hemifields. Participants associated the green stimulus with the word "yes" and the red with the word "no" while responding to the question whether an auditorily presented number was even or not. They communicated their response only by directing their attention to the respective surface, while fixating their visual gaze on a cross in the center of the stimulus device. The online decoded response was presented as feedback auditorily by a female voice saying the words "yes" or "no".

Data of single participants can be loaded in Matlab (e.g. load P01.mat) which reveals the structures subject and bciexp. The fields of these structures are described in detail in the file Description.pdf. In short, the EEG data are segmented in trials (each comprising a series of visual stimuli during which participants responded to a question by their spatial covert attention) and are stored in bciexp.data We also provide example scripts in example.zip that show how the data could be analysed using the ERPCCA toolbox: https://gitlab.com/christoph.reichert/erpcca