Cognitive dysfunction, as the name implies, is when a patient’s cognitive function is impaired. Cognitive functions can be divided into memory, calculation, thinking comprehension judgment, orientation, executive functions, etc. A common cognitive dysfunction is dementia, which is a very serious cognitive dysfunction. Patients often suffer from impairment in various parts of cognitive function, which leads to a significant decline in social functioning and even the inability to live independently and the need for care. Other relatively common cognitive dysfunction, including MCI, or mild cognitive impairment, is a pre-morbid manifestation of dementia, which means that although the patient has cognitive impairment, social functioning remains relatively good and he or she can still live independently with the reminder of others or the assistance of others. If an elderly person around you is found to have developed cognitive impairment, it should be recognized and treated by a specialist in a timely manner.