It is commonly observed — but not commonly enough! — that old folks removed from their homes to hospital settings are put at a tremendous disadvantage, even though their basic bodily needs are well provided for. They often to be quite demented — to be utterly incapable of feeding, clothing, and washing themselves, let alone engaging in any activities of greater interest. Often, however, if they are returned to their homes, they can manage quite well for themselves. How do they do this? Over the years, they have loaded their home environments with ultrafamiliar landmarks, triggers for habits, reminder of what to do, where to find the food, how to get dressed, where the telephone is, and so forth. An old person can be a veritable virtuoso of self-help in such a hugely overlearned world, in spite of his or her brain's increasing imperviousness to new bouts of learning... Taking them out of their homes is literally separating them from large parts of their minds — potentially just as devastating a development as undergoing brain surgery.
Daniel Dennett