Dr. Hamada received his Bachelor's degree in Experimental and Mathematical Psychology (1971) from Tokushima University, his Master's degree in Color Vision (1973) from Osaka Kyoiku University, and his PhD degree in Experimental and Mathematical Psychology (1980) from Hokkaido University in Sapporo, Japan. Based at Tokushima University since 1982, he has been Professor Emeritus since 2013. In 1991 he was a guest scientist at Department of Sensory Neurophysiology of Institut für Arbeitsphysiologie at Dortmund University, Germany. His main research areas are in symmetry cognition, contour perception, brightness illusion, geometrical illusion, and negative time-order effect on weight sensation.