Dr. Kawashima was born on May 23, 1959. In the 1970s, he enrolled at Tohoku University and graduated with an M.D. at the school of medicine. He has written various books on his studies on the brain, and is very well known in Japan.
After the launch of the Nintendo DS, Satoru Iwata presented him the idea of the original Brain Age; as part of the Touch Generations series, the game would consist on a series of mental exercises based upon Dr. Kawashima's Train Your Brain book. The title was supervised by Dr. Kawashima, and it even featured a polygonal head representing him.
Dr. Kawashima would continue to work with Nintendo with the following Brain Age titles, including Brain Age 2, all Brain Age Express titles (including Math, Arts & Letters and Sudoku) and Concentration Training.
- Brain Age: Train Your Brain in Minutes a Day! (2005) - Supervisor
- Brain Age 2: More Training in Minutes a Day! (2005) - Supervisor
- Brain Age Express: Math / Arts & Letters/Sudoku (2008) - Supervisor
- Brain Age: Concentration Training (2012) - Supervisor
- Dr. Kawashima's Brain Training for Nintendo Switch (2019) - Supervisor
- Dr. Kawashima has also worked with Namco Bandai on Brain and Body Movement on Xbox 360.
- His in-game character has also appeared on games like Super Smash Bros. for Nintendo 3DS/Wii U and Super Mario Maker.