Hilary Judging from our three years of community-based cognitive intervention for the elderly, the core characteristics of cognitive health in the elderly are strong individual heterogeneity and a significant decline in the ability to resist fluctuations in cognitive homeostasis. It is almost impossible to find a unified judgment standard that can be applied to all elderly people.
Take two 76-year-olds in the community we serve as examples. Aunt Wang, who worked as a middle school Chinese teacher before retiring, can still write more than 2,000 words of memoirs every day and play mahjong and card counting with her old friends so fast that even young people can’t beat her.； Uncle Zhao, who is the same age, has worked hard all his life and has not studied for a few years. Since last year, he often forgets to turn off the gas and forget to bring his keys when going out. He has gone to the hospital several times for examinations. He has no pathological indications of brain atrophy or Alzheimer's disease. The doctor only said that it is a normal sign of aging.
Academics often use the metaphor of "cognitive bank". When you are young, you have a high level of education, maintain the habit of using your brain all year round, socialize a lot, and do not have chronic diseases such as high blood pressure and diabetes that can damage blood vessels. This is equivalent to depositing a thick reserve in the cognitive bank. Even if the nerve cells naturally die when you get older, it is enough to support normal cognitive functions and there will be no obvious decline.； Elderly people with low reserves may experience significant memory decline just after the age of 70. This is why cognitive status can vary greatly at the same age.
In addition to the differences between people, the cognitive status of the same old person also fluctuates much more than that of young people. You would think that young people who stay up all night will be unresponsive the next day at most, and can recover after sleeping for one day. If the elderly do not sleep well for three or four days in a row, or have a cold and fever, they may not even be able to remember what they just ate. Many family members will panic at this time, thinking that they have dementia. In fact, As long as the sleep and physical state are adjusted back, most people can return to their previous levels within a week. To put it bluntly, the cognitive state of the elderly has weakened the "resistance" ability and cannot withstand too severe state fluctuations. However, as long as the adjustment is timely, the reversibility is actually higher than everyone thinks.
There are still different opinions in the academic circles as to whether cognitive decline will inevitably occur in old age. The previous traditional view was that nerve cells cannot regenerate, and cognitive decline is an inevitable trend with age. However, in recent years, tracking studies on "successful aging" groups have found that almost 15% of elderly people in their 80s and 90s have no significant difference in cognitive test scores from healthy adults in their 50s and 60s. One group of scholars believes that Because as long as cognitive reserve is sufficient and the lifestyle is healthy, cognitive ability can be maintained at a normal level throughout life. The other school of thought believes that the rate of cognitive decline of this type of elderly people is extremely slow, masked by high reserves, and that there is still a decline in nature. Currently, both sides are supported by large-sample studies, and a unified conclusion has not yet been formed.
We often encounter very interesting situations when doing cognitive screening in the community: some elderly people are very good at playing with their smartphones. They can browse short videos, buy groceries online, and video chat with their grandchildren in other places. However, they lose points when doing attention switching and abstract reasoning questions in cognitive tests.； On the other hand, there are also elderly people who cannot use smartphones at all. They can talk about their work experience decades ago in a clear and logical manner, and they can calculate their family's income and expenses without making any mistakes. This also shows that the pace of decline in different cognitive dimensions of the elderly is completely asynchronous. It cannot be said that "the brain does not work well as you get older". Some elderly people may have poor memory, but their logical reasoning ability is completely online. Some elderly people are slow to learn new things, but their long-term memory and calculation ability are very good. As long as it does not affect their normal life, they are all healthy.
To be honest, the longer I work in this field, the more I feel that there is no unified "standard answer" for cognitive health in the elderly. Many family members get extremely nervous when they see the elderly forgetting things. They insist on taking various brain supplements, which in turn makes the elderly very stressed. The increased anxiety will increase the cognitive burden. It is really unnecessary. As long as the elderly feel that their daily tasks are smooth and there are no life-impacting situations such as getting lost, miscalculating accounts, or not recognizing acquaintances, even if they occasionally forget to bring their keys or forget what they just said, it is really normal.
