If you, a young person, told me, that you would like to start wearing glasses, using crutches and sometimes a wheelchair, I might conclude that you are a little bit crazy. In the best case, I would think that you are involved in an aging experiment…
This morning, I read a report about a very famous and (of course) successful conductor who recently extended his contract. He promised to an also renowned orchestra to lead it for the next four years. The man is 84 years old, practices at his piano more than four hours every day, reads books, writes articles and teaches students of master classes. Of course, he might be an exception.
But “older people” does not automatically mean “brain- amputated people”! :-)))
Why should an older brain not have enough capacity for learning new things if it is not impaired by illness? By the way, dementia cannot be prevented by learning new things – there are enough examples of highly motivated learners and “brain-workers” who used to achieve best results in their sciences. "Suddenly" they were hit by dementia (they are able to conceal their disease for a long time with help of their intelligence). Even people who have to suffer from dementia are able to learn until to the middle stage of (Alzheimer-) dementia. They can learn until the cells and structures of their brains are completely destroyed and they finally need assistance round-the-clock.
I have no illusions: Language learning can certainly not be a magic medicine against aging and cognitive impairments. But language learning can enrich the life of an older person: There are duties (just toward oneself), goals, a self-given program, joy about some success, discomfort because of the insight into failures – briefly: a full and reasonably filled LIFE, which is in every case better than to sit in front of the TV for the whole day.
With the beginning of my retirement and the gained leisure time, I started to learn ONE language. Why not four languages (following to the motto: the more the better)??? I don't want to be a slave of an "anti-aging program" with a very predictable ending. I just want to employ my mind with interesting things.