I was working at home the other day when I heard a knock at the door.

A woman I’d never met had an unusual request. 

“My mother is 97, and she lived in this house when she was a little girl. Would it be OK if she had a peek inside?”

OK? It would be more than OK. I’ve lived here for almost 30 years, but the house is much older than that, built around 1880. I was wondering what it would look like to someone who was here last nearly 90 years ago, when the building was younger than I am today.

She was quite spry and came into the yard with a little help from her two daughters. Right away she noticed that an owner between her time and mine had covered up some decorative shingles with aluminum siding. I had to agree that it was too bad.

Inside, she noticed some more shocking differences. “It used to be bigger,” she told me. And “the house next door used to be farther away.”

I wasn’t around in the 1930s, but I’m pretty sure that she’s wrong. It’s true that the house is small, but no smaller than it was the day it was built, according to the records at the county registry. 

And the place next door is right where it was when the city tax assessment photos were taken in 1924. 

The buildings haven’t changed. It’s just that they are about the only things that haven’t.

And that’s how memory works. What looked big to a 3-foot-tall 8-year-old stays big as the years roll by. We forget how much of what we think we “know” and “remember” is a story that we’ve told ourselves that can be added to and subtracted from over time.

I used to be proud of my memory. I would drive my family crazy by repeating long strings of dialogue from a movie I’d watched only once, or the sequence of plays in an exciting baseball game. But at 58, I know not to trust it anymore.

I was at a party a while back and met a woman who I remembered from a meeting I had covered as a reporter 20 years or more earlier.

I knew that she was part of a development group that was proposing a project in Falmouth.

I remembered that project hit a snag because an endangered species had been discovered on the land – a rare grasslike plant called “variable sedge.” The developers came up with a plan to move the sedge outside the proposed building’s footprint, and they were so proud of it that they were going to name their project – which happened to be a memory care facility – Sedgewood Commons.

I remembered all that, but I couldn’t remember her name.

We laughed about it, but I was embarrassed. And it happens to me all the time. How can you remember someone and forget their name? 

Psychologists have a word for that phenomenon: “lethologica,” which just means something like “forget the word” in Greek.

It happens because our minds are not computers and our memories are not stored in files, waiting to be retrieved. They come back to us when they are associated with new information. I associate the story of the project with things that come up from time to time, like Falmouth, planning boards, endangered species and, especially, fear of dementia, which comes up a lot.

But a rarely used word, like an individual’s name, has fewer associations and can get lost in the stacks.

As we continued the tour, my visitor had a lot of associations about the house we have shared, at different times, for the better part of a century.

There were six children in her family, which blew me away. This place seemed tiny when my two daughters were growing up. I don’t think I would have remembered it as big if I had shared it with seven other people.

Mostly, though, she remembered what wasn’t there anymore, like a huge pantry filled with delicious food. I opened a closet door near the kitchen. “Is this it?” I asked hopefully. But I could see her disappointment to find only a washer and dryer.

After a few minutes her daughters helped her get back to their car, and we said goodbye.

As they drove away, I realized I’d forgotten to ask her name.