Let's prevent dementia with simple brain training.

Human cognitive function seems to decrease at the peak in the late 20s "if nothing is done".
However, if you train the brain, your learning ability will start to improve again.
The more people who regularly work on puzzles, the better the task of evaluating attention, reasoning, and memory, and on average, they have brain functions that are 8 years younger than those who are not working on it.
The main effects that can be expected for brain training are improvement of children's abilities, prevention of aging of the brain, prevention of dementia, and maintenance of abilities for people with dementia.
In other words, brain training is useful throughout one's life.
However, brain training can be stressful and impair the effect if it is not fun.
Why don't you find and work on brain training that you can enjoy?
"Curiosity" is the most secret to bringing out the effect of brain training.