Incomplete myelination of the white matter of the brain of one-year-old babies will cause the phenomenon of excitatory generalization, which is usually manifested by decreased muscle tone, mental retardation, developmental delay and so on. 1. Decreased tone: the decreased muscle tone of one-year-old babies may even affect the movement of babies, and in serious cases, it may also affect the children’s swallowing of food and so on. 2. Mental retardation: it shows mental retardation, and there are also complications such as epilepsy. 3. Developmental delay: myelinization of the white matter of the brain will make the hormone metabolism of one-year-old babies abnormal, the hormone secretion will lead to the growth and development of the relevant organs, which in turn affects the metabolism of the whole body. If the above symptoms occur, it is recommended to go to the hospital in time, early formal treatment.