> I wonder if those who went to sleep earlier and slept longer did so because they were generally less busy and involved in things.
Really. Life is for living, there’s too many things to do to sleep one’s life away. Me, I generally rotate around about 7 or so hours.
Same here, though I don’t mind a brief nap on a hot afternoon. I suspect that idleness may well correlate with developing dementia, but it’s certainly not the sole cause.