In the presentation, I will introduce the research and recent findings of our team in the field of measuring brain biopotentials. It turns out that these psychobiological signals reflect ongoing information processing, human states, and sometimes even some of our national characteristics. In any case, these are studies that cannot yet be replaced by re-analyzing information in big data repositories, as the exploration of what  do they show is still ongoing. However, by combining rich background information and careful experimental studies, new opportunities for understanding humans may emerge.