This project aims at developing cognitive mirroring systems that make human cognitive processes observable. We hypothesize that predictive coding in the human brain plays a crucial role in cognition and intend to better understand its principle and mechanism with/without developmental disorders by integrating computational modeling approach and Tojisha-kenkyu (first-person view research of developmental disorders). Cognitive mirroring systems, which we design based on the theory of predictive coding, will assist people with developmental disorders by means of self-understanding and social sharing of their cognitive processes.