Forgetfulness is a manifestation of weakened brain function in the elderly, while dementia is a pathological organic brain intelligence decline. How to distinguish the two, the following points can be referred to: Forgetfulness difference: forgetful elderly people’s forgetfulness of what they have done is always partial; while dementia’s forgetfulness is completely malignant, unable to remember what has happened, as if the matter has completely disappeared. Du Juan, Department of Neurology, Beijing 306 Hospital Cognitive ability: Although the amnesic elderly have decreased memory, their cognitive ability to recognize time, place, relationships and surroundings is not diminished at all; whereas the demented elderly have lost the cognitive ability to recognize their surroundings, cannot distinguish between morning and afternoon, do not know the change of seasons, do not know where they are, and sometimes cannot even find their way home. The elderly with amnesia are able to take care of their own lives and even take care of their family members, although they may misremember dates and sometimes forget after they have spoken. Emotional changes: The forgetful elderly have seven emotions and six desires, while the emotional world of the demented elderly becomes “indifferent” and insensitive. Changes in thinking: The forgetful elderly are very distressed by the loss of memory and often write down a memo in order not to miss things, while the demented elderly are not bothered, their thinking is getting slower and slower, their speech is getting poorer and poorer, they lack a sense of humor and are slow to respond. Whether the language is rich and colorful humor is one of the important signs to distinguish between physical forgetfulness and dementia.