痴呆(dementia)和精神发育不全(mental retardation)是神经系统遗传病的常见症状,但两者易混淆。痴呆是指中枢神经系统发育已完善,因各种疾病引起脑部损害所出现的智能减退,也就是获得性智能 Dementia and mental retardation are common symptoms of neurological disorders, but the two are confusing. Dementia refers to the central nervous system development has been completed due to various diseases caused by brain damage caused by the intellectual decline, which is acquired intelligence