Pictures!
I first got the genealogy bug when closing down my widowed, childless uncle's place when Alzheimer's got too overwhelming. (In the form of four crates of diaries, correspondence and genealogy work his father, uncle and grandfather did over half a century.) Uncle's emergency room crisis that meant he never went "home" again happened on 9/11, and he never was able to remember those crashing airplanes because his short term memory was that far gone. I had a variety of responsibilities. I learned quickly that the more he was distracted from the confusing, cacophonous present, the better. He had boxes and boxes of pictures, many unlabeled. Some of our best times back then were when I got him talking about stories and memories triggered by the pictures. Even without Alzheimer's, it's a great way to trigger memories. And it's a really good thing to get the people in old pix IDed while there's still someone around who remembers them!
In a non-genealogical vein: Some years back, I had a tribal environmental job. I gathered some historic pix (Denver Public Library, Library of Congress kinda public sources.) Many of the tribes ban cameras from a lot of events nowadays where they didn't know what those Kodak cameras were when they first showed up in the 1890s, and many have since found their way to various archives. My job occasionally required making presentations to an advisory panel of elders. One day I showed up with a pile of said library pictures, and the room went wild, with the convening gavel being postponed. All kinds of talk about when the first sewing machines came and where they dried fruit in the fall and how they cleared snow. So on and so forth.
FYI: If ever you've got an Alzheimer's patient to look after, I've got a tip. When you find a joke, repeat it. Often! Every half hour or so!! There's a lot that's challenging about that caretaker role. It's cool to be able to get that fresh, delighted laughter over and over and over and over again for the same punchline, and it keeps the afflicted one relatively happy. Not unlike the old pictures do.
Pictures!!