Random long termers to keep an eye on.   Tony Mendez of real life Argo fame, showed up on Channel 5's Greatest Spy Films. They prefaced his talking head bits with the news that he has Parkinsons, and had his wife by his side to help him speak/recall things.   Wendy Williams, TV actress, was a talking head in a Dr Who thing - for Ark in Space - from 2013 and looking both old for her then late 70s, and possessing the stuttered voice of someone who'd suffered a stroke at some point.