Inclusion Criteria:  - Age 60 to 70, gender is not limited.  Exclusion Criteria:  Delirium, confusion, confusion of consciousness. Alzheimer's disease, Parkinson's disease, stroke, cerebral hemorrhage, brain tumor, hydrocephalus. Viral, fungal, and syphilis infections. Sufferers from cerebrovascular disease (as demonstrated by a Hachinski ischemic score, or neuroimaging test). Repeated mild head trauma, or head trauma resulting in loss of consciousness (more than 1h). Depression, mania, and other mental disorders. Alcoholism and drug dependence. The following diseases may lead to mental retardation:  Kidney disease, respiratory system disease, heart disease, liver disease, uncontrolled diabetes, endocrine, metabolic, blood disease, malignant disease, more than 2 years have not been relieved.  Taken any medication that may cause psychosis or affect intelligence in the past 1 month. known allergy to phosphatidylserine or related ingredients.