痴呆已被认为是目前世界上主要的“流行病”之一,大多数发生于老年人。老年性痴呆就是指发生于老年时期但又不属于老年人正常的精神变化的痴呆。其临床典型表现有记忆力、抽象思维、定向力的障碍,同时伴有社会活动能力的减退,其智能损害必须是后天获得的和持续性的,以与其它疾病引起的痴呆相区别。其痴呆具有以下标志:1.社会功能 Dementia has been considered as one of the major “epidemics” in the world at present, and most of them occur in the elderly. Alzheimer’s refers to dementia that occurs in old age but does not belong to the normal mental changes in the elderly. Its typical clinical manifestations of memory, abstract thinking, disorientation of orientation, accompanied by diminished ability of social activities, its intellectual impairment must be Acquired and persistent to distinguish from other diseases caused by dementia. The dementia has the following signs: 1. Social function