Recently, an article of Human Science ABO Center's blog
Relationship between brain activities and blood types -- What I learned from the experiment (in Japanese)
Source: Blog of ABO Center
The Human Science ABO Center and Dr. Munetaka Haida (Tokai University) have been conducting a joint research on relationship between brain function and blood types for over 10 years.
According to this article, a "photo topography" experiment to measure activities of the human brain showed a spectacular contrast.
Type A = activity of the left brain is high (logical activity)
Type B = activity of the right brain is high (sensory activity)
Although, there were relatively less differences between Type O and Type AB:
Type AB = using both the left and the right brain simultaneously
Type O = using both the left and the right brain alternatively
From these results, it can be said that blood types, the left and the right brain are related to each other. We might be one step closer to the truth!