Many magicians fall into the trap of performing a "show" at a Senior Care Center. In other words, they get the Seniors in the standard audience places, even if they have to be wheeled into place, and then they expect to perform the show standing at one end of the room and let the seniors watch them perform.
In my experience, having been on both sides of that trap, that is completely the wrong approach. You are better off in a table hopping kind of performance, as the seniors finish a meal in their cafeteria.
Seniors want to meet YOU. They want to talk to YOU. They want you to listen to THEM. They will tell you marvelous stories of the time they went to see Blackstone (or whomever). The magic you do will get them talking and remembering.
Do personal tricks- like the sponge balls where the ball appears in their hands. Keep it simple. Don't challenge their short term memories by asking them to remember a chosen card for very long. Tear the card up, hand them the pieces and let them restore it and open it up themselves.
Talk to them and then be prepared to listen if they want to talk to YOU. If you do, some of them may actually remember you if you go back again. They may even tell stories about YOU to their children or grandchildren on visiting day.
Don't buzz in, show off a bit, and then buzz off. They won't remember you any more than they remember what they saw on the TV news that day.
Give them memories of someone who came by to talk to them and... oh yes, he was the most marvelous magician. I don't recall exactly what he did, but he was very magical.