Alfred Eisenstaedt—Time & Life Pictures/Getty Images
Caption from LIFE. "Dementia praecox exiles the young to a world of their own. Manic-depressive gazes continuously through barred window."
Ed Kashi / Corbis
Arden Peters comforts his wife, Mazine, who has end stage Alzheimers.
Jeff Mermelstein / Gallery Stock
Engaging the brain with games like mah-jongg can delay the onset of dementia but lead to faster-progressing disease once it emerges.