Kim and Yi (Seoul University of Venture & Information) measured the brain waves of 4,636 adults. They reported that type O people were most stress-resistant. Moreover, an experiment using light topography instruments by Munetaka Haida (Tokai University School of Medicine) suggests the possibility that activated parts of the human brain are different according to blood types. i.e. type A’s left brain is superior to the right, while type B’s right brain is superior.