Spend enough time with McKinnon and it’s hard to escape the creeping sense that she’s not just different—she’s lucky. Memories that would be searing to anyone else leave little impression on her. Like the time in 1986 when the couple was living in Arizona and Green was jumped by a group of white men while out fishing. When he came home, his head was covered with welts. “She went to get ice and she started crying,” Green says. He began to cry too. They felt terrorized.

Once again, McKinnon knows the salient facts of the story, but the details and the painful associations all reside with Green. For McKinnon, the memory doesn’t trigger the trauma and fear associated with it. “I can imagine being upset and scared, but I don’t remember that at all,” she says. “I can’t put myself back there. I can only imagine what it would have been like.”

McKinnon also quickly forgets arguments, which might be the reason she and Green have stayed together so long, she jokes. She cannot hold a grudge. She is unfamiliar with the feeling of regret and oblivious to the diminishments of aging. A 1972 yearbook photo shows that she was once a petite brunette with a delicate face framed by a pixie cut. (“Dorky little innocent thing,” she says, looking at the picture.) On an intellectual level, McKinnon knows that this is her; but put the picture away and, in her mind, she has always been the 60-year-old woman she is now, broad-­shouldered and fair, her face pinkish and time-lined, her closely cropped hair white and gray. She doesn’t know what it’s like to linger in a memory, to long for the past, to dwell in it.

More than a decade ago a woman named Jill Price came to the attention of scientists at UC Irvine. She exhibited a condition that is pretty much the direct opposite of McKinnon’s: the researchers called it hyperthymestic syndrome, or highly superior autobiographical memory. Price has an extraordinary ability to recall just about any fact that has intersected with her life: July 18, 1984, was a quiet Wednesday, as she writes in her memoir, and Price picked up the book Helter Skelter and read it for the second time. Monday, February 28, 1983, the final episode of M*A*S*H aired, and it was raining. The next day Price’s windshield wipers stopped working as she drove.

In contrast to McKinnon, who has received relatively little press attention, Price became an instant media sensation. Diane Sawyer had her on air twice in one day. Her powers of memory, after all, seemed supremely enviable, superhuman.

But as the UC Irvine researchers—and a story in WIRED—noted, Price’s extraordinary feats of recollection were accompanied by a kind of obsessive-compulsive fixation on recording the details of her life, one that appeared to have taken root after a “traumatizing” move to LA when she was a girl. As an adult in her 40s, she still lived with her parents. And she buttressed her memory with cramped pages full of notes on everything that happened to her in any given day.

Which is all just to say: When it comes to people with highly unusual memories, it’s not clear that we as a culture are so good at choosing who to envy.

You might think that McKinnon would lean on technology to help compensate for her disorder. After all, she lives at a moment when software companies are churning out products that are, essentially, surrogates for the very faculties she lacks. Isn’t a Facebook feed a kind of prosthetic autobiographical memory? Google Photos will even form gauzy retrospective mental associations for you: The artificially intelligent software plunges straight into your photo library, plucks out faces and related events, and automatically generates poignant little videos—synthetic episodic memories. Other software tools aim to capture your entire life in documents—emails, calendar reminders, schoolwork, voicemails, texts, snapshots, videos, and other bits of recordable data—to provide a searchable database of your memories.

And yet the life-logging impulse is lost on McKinnon. Once, she decided to keep a journal to see if she could preserve her memories. “I stopped doing that after two or three days,” she says. “If I get so obsessed with capturing every moment because I’m afraid of losing the memory, I’m never going to experience those moments.” And what else, really, does she have?

She does use email, which sometimes serves as a useful reference. But she doesn’t make a special effort to log her experiences there. And she doesn’t use social media. No Pinterest. No Instagram. She had a Facebook account, but she quit using it. It didn’t interest her.

Even if she had a Facebook feed, she would have very little to put there in the way of photos or videos. McKinnon once borrowed a video camera to film one of their departures on a Caribbean cruise, but she didn’t enjoy it. She lost the feeling of the moment, she says. She likewise doesn’t take photos. She says she doesn’t find them that compelling to look at. Sure enough, I notice there are no pictures on the ­couple’s refrigerator, shelves, or walls. No framed wedding portraits. No posed beach shots. There are just a few photo albums in an upstairs office.

McKinnon pulls down the album of her 1981 courthouse wedding to Green in Maywood, Illinois. There’s a shot of the friends who surprised the newlyweds on the steps outside. There’s one of Green opening a gag gift—a set of four mugs with images of cats having sex. McKinnon is practiced at laughing through all the anecdotes about the day that she has memorized over the years, with help from the album. But looking at the pictures, she says, feels like observing somebody else’s wedding.

Today, though, she learns something new about the day she married Green. As we look over the album, Green mentions a close friend who attended the wedding. “I didn’t even know she was there,” McKinnon says. That’s because there are no photos of this friend. Because she was the one behind the camera.

This actually feels like the kind of error anyone could make: Doesn’t the person behind the camera often get edited out of recall? Even when the person behind the camera is you?

McKinnon is practiced at laughing through all the anecdotes about her wedding day that she has memorized over the years.

While it’s abundantly clear that McKinnon isn’t using technology to become more like us, it’s conceivable that technology could, over the long run, make us all a bit more like McKinnon. My iPhone now holds 1,217 photos and 159 videos just from the past eight months. By focusing on clicking picture after picture, I may actually be blurring away my memories of these experiences through something researchers call “the photo-taking impairment effect.” And by automatically storing all those photos in the cloud—which relieves my mind of the burden of cataloging a bunch of memories—I may be short-circuiting some part of my own process of episodic memory formation.

“What would humanity lose if they lost some of that ability?” McKinnon asks during one of our conversations, as if wondering aloud for me. “If they had technology to replace it, what would be lost? The human experience would change, but would it be a plus? Or a minus? Or—just a change?”