抄録
The limbic system, or the old cortex, is usually treated as a system. However, the function of the system as a whole has not been discussed much so far. Parts of the system are usually talked about separately in relation to memory, emotion and so on. In this paper, the function of the system as a whole is discussed with the key words: the ordinariness, or the ordinary, and the extraordinariness. The ordinariness is a concept which consists of or can be replaced by a daily life, or the present, or the usual, or no novelty. The limbic system forms the ordinariness in the brain in relation to the neocortex. Human beings and the other animals have the ordinariness in common, and the ordinariness is important to live and survive in the
actual world. The function of the cerebellum appears to be understood relatively well (Igaku-shoin, 2019). With the discussion in Sato (2017), in which the structure and function of the cerebral eocortex are talked about, the structural function of the brain as a whole can be finally understood.
