Why Do Some Memories Survive Dementia?

Summary

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Podcast Summary: The Daily

Episode: Why Do Some Memories Survive Dementia?

Date: July 26, 2026
Host: Rachel Abrams (The New York Times)
Guest: Ellen Berry, reporter; Priya Rajasetapati, neuroscientist

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Overview

This episode explores the mysteries of memory and dementia through the deeply personal story of New York Times reporter Ellen Berry and her late father. After his fall and subsequent brain injury, her father developed dementia, leading to the profound loss of recent memories and disorientation, yet retaining vivid memories from his distant childhood. The episode weaves Ellen’s experience with new neuroscientific findings, offering insight into why some memories survive dementia, and discusses emerging research that may one day help preserve the most essential human memories.

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Key Discussion Points & Insights

Ellen Berry’s Family Story: The Onset of Dementia

• Prompt for Returning Home:
  Ellen moved her family back to the U.S. from India to support her aging parents in a multigenerational housing arrangement ([05:14]).
• The Injury:
  Just before the move, Ellen’s father suffered a severe fall; a brain scan revealed a subarachnoid hemorrhage ([05:40]).

  “Once they were able to do a brain scan, they told us that he had a subarachnoid hemorrhage, like he had had a brain bleed.” — Ellen Berry [05:41]

Cognitive and Behavioral Changes

• Initial Recovery and Hope:
  Early signs suggested her father was recovering. However, this was the onset of accelerated vascular dementia ([07:00],[07:34]).
• Bizarre Delusions and Disorientation:
  • He believed his roommate was smuggling caviar and nurses were KGB agents ([08:04]).
  • Loss of understanding about where he was, attempts to leave the facility ([08:44]).
• Home Life and Escapist Behaviors:
  • At home, he retained old routines but became impulsive, ordering multiple items online or wandering away ([10:18],[10:55]).
  • He persistently felt he was in the wrong place and fixated on leaving for invented trips ([12:02]).

  “He said he had to leave the next morning to take a water route to China, which from Massachusetts... doesn’t make a lot of sense.” — Ellen Berry [12:20]

• Family Strategies:
  The family tried everything from notes on the door to driving him to the airport to soothe his compulsions ([13:13]).

  “We would try to redirect him... My husband, God bless him, sometimes took him to Logan airport and just let him walk into the terminal and then come back to the car.” — Ellen Berry [13:32]

Memory Loss: What Went and What Stayed

• Recent Memory Loss:
  Her father could not remember recent events or understand the family’s house arrangement ([15:18]).
• Clarity of Distant Memories:
  In contrast, childhood memories surfaced with vivid detail, such as the story of losing his canary at age six ([16:00]).

  “He was telling this story... When he was six years old, his family left Pittsburgh ... he was able to take one pet. The pet was a canary...” — Ellen Berry [16:15]

• Recognition of True Memories:
  Unlike delusions, the childhood memory was intact and deeply emotional ([18:06]).

Neuroscience: Why Do These Memories Survive?

• Connecting Life to Research:
  After her father died, Ellen saw a press release about new memory research. She contacted Dr. Priya Rajasetapati to understand what had happened ([21:00]).
• Analyzing Her Father’s Brain Scan:
  Dr. Rajasetapati found damage in the right hippocampus (key for location and recent memories) ([23:20]).

  “[The] injury was on the right hippocampus, which is the part of the brain that organizes your sense of place and location.” — Ellen Berry [24:29]

How Memory Works—And Why Some Remain

• Hippocampus vs. Cortex:
  The hippocampus encodes and differentiates new memories; older, emotionally significant memories get transferred to the cortex and are more protected ([25:27]).
• The Thalamus as Gatekeeper:
  Dr. Rajasetapati’s research shows the thalamus determines which memories are important enough to store safely ([25:54]).

  “Our brains naturally say what's important... and the thalamus gates it and transfers [it] to cortex.” — Priya Rajasetapati [26:02]

• Which Memories Survive?
  The intensity (valence) of an experience—whether highly positive or negative—may decide if it’s “offloaded” to a safe place in the cortex ([26:49]).

  “If it’s high on the valence spectrum... we can see them selected at the level of the thalamus.” — Priya Rajasetapati [26:49]

• Implications for Dementia Care:
  Understanding these mechanisms could help families and, potentially, lead to therapies that stabilize essential memories ([27:33]).

  “If you could somehow learn to manipulate that gatekeeping mechanism... you could move those memories out of the damaged parts of the brain into healthier long-term storage before they're lost.” — Ellen Berry [27:39]

Emotional and Practical Takeaways for Families

• Understanding vs. Changing Dementia:
  Ellen and her husband grappled with realizing they had been powerless to change her father’s experience ([29:38]).

  “...We didn't really understand that there was a permanent change... we couldn't talk him out of it. We couldn't retrain him...” — Ellen Berry [30:46]

• Advice for Caregivers:
  Knowing the permanence and neurological basis of these behaviors can help families accept, adapt, and provide more compassionate care ([30:46]).
• The Value of Research:
  Even if nothing can be reversed now, the hope is that future research will allow key memories—recognizing family, feeling safe—to be protected ([28:37]).

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Notable Quotes & Memorable Moments

• “And the way my dad always told this story, he would say, and I woke up married. That was a story that my dad would tell even after his brain injury and dementia had really scrambled many of his memories.” — Ellen Berry [01:24]
• “He said, fancy meeting you here.” — Ellen Berry (on finding her father at a nursery in the middle of the night) [11:50]
• “Bob, you live here. Don’t move. We love you.” — Ellen Berry (sharing the note her husband wrote) [14:26]
• “It was perfect. Like a bell jar. It was like perfectly preserved.” — Ellen Berry (on her father’s memory of losing the canary) [18:00]
• “Our brains naturally say what's important. The canary is important. Meeting my wife was important... and the thalamus gates it and transfers to cortex.” — Priya Rajasetapati [26:02]
• “If you could somehow learn to manipulate that gatekeeping mechanism... you could move those memories out of the damaged parts of the brain into healthier, long-term storage before they're lost.” — Ellen Berry [27:39]
• “Understanding what’s happening in the brain doesn’t mean that you can stop it or reverse it, but it may prepare you better for accompanying them to the end.” — Ellen Berry [31:28]

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Important Segment Timestamps

• Ellen Berry’s story and her father’s fall: [04:48]–[07:00]
• Emergence of delusions, impulsiveness: [07:34]–[12:02]
• Compulsions to leave, family caregiving strategies: [12:02]–[15:37]
• Discovery of childhood memory (canary story): [15:42]–[18:06]
• Ellen’s search for neuroscientific answers: [21:00]–[24:29]
• Explanation of brain mechanisms—hippocampus, cortex, thalamus: [24:29]–[27:05]
• Potential for future therapies and memory preservation: [27:33]–[28:37]
• Emotional reflections on caregiving, acceptance: [29:38]–[31:40]

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Conclusion

By combining moving personal narrative with the latest neuroscience, this episode of The Daily offers both comfort and clarity to those coping with dementia in their families. It brings scientific hope while honoring the lived reality of loss, memory, and adaptation, and leaves listeners with a deeper understanding of why certain memories—whether joyful or traumatic—persist even as others fade.

Transcript

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[Ellen Berry]

was this story that my dad always told about how he fell in love with my mother. Both of them were living in Europe. It was 1956. My dad was a student, and he had become so passionate about the student uprising in Hungary that he decided to spend his Christmas break assisting the revolution. So he and a friend made plans to travel down to the border of Hungary and Austria. My mom, who was at that point an acquaintance, tagged along, but when they got there, she stayed behind and they crossed the border into Hungary. It wasn't long before they encountered a row of Soviet tanks, at which point they decided their work here was done and retreated. Instead, they decided to leave the Hungarians to their own devices and spend the rest of their winter break skiing. Now, my dad had never been on skis, and this is sort of characteristic that the way he approached it was essentially to get on a ski lift to the top of an alp, where I guess he imagined that he was going to learn how to ski by skiing down it and almost immediately dislocated his shoulder. And someone called a medic. And in preparation for resetting the shoulder, the medic handed my mother a rag soaked in chloroform and told her to hold it over his mouth, which she did. And the way my dad always told this story, he would say, and I woke up married. That was a story that my dad would tell even after his brain injury and dementia had really scrambled many of his memories.

[Rachel Abrams]

From the New York Times, I'm Rachel Abrams, and this is the Daily on Sunday. Over the course of a few years, Times reporter Ellen Berry watched as her father's memories slipped away to dementia. It is the kind of painful experience that a lot of families suffer through, often in isolation. Today, Ellen recounts her journey with her father and how years after his death, one neuroscientist helped to explain to her what had happened to him and what her family had gone through. It's Sunday, july 26th.

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This podcast is supported by the American Petroleum Institute. Energy security affects how Americans live, work, travel, and stay connected. America has abundant oil and natural gas. But resources alone are not enough. The country needs modern infrastructure like pipelines and transmission lines that can affordably and safely bring energy to families, communities and businesses. That's how to build a stronger, more reliable energy system for the future. Learn [e-mail] this podcast is supported by Vanguard. To all the financial advisors listening, let's talk bonds for a minute. Capturing value in fixed income is not easy. Bond markets are massive, murky and let's be real, lots of firms throw a couple of flashy funds your way and call it a day. But not Vanguard. Vanguard bonds are institutional quality. Institutional quality isn't a tagline, it's a commitment to your clients. It means top grade products across the board. The Lineup includes over 80 bond funds. They're actively managed by a 200 person global squad of sector specialists, analysts and traders. The bond market is complex and it's not something one person or a small team can realistically keep up with. Vanguard's been in the game a long time and their scale gives them a serious edge. They're able to invest across all kinds of sectors, maturities and geographies. So if you're looking to give your clients consistent results year in and year out, go see the record for [e-mail] audio get that's vanguard.com audio all investing is subject to risk. Vanguard Marketing Corporation Distributor Ellen Berry welcome

[Rachel Abrams]

to the Sunday Daily.

[Ellen Berry]

Thank you.

[Rachel Abrams]

Ellen, you were a foreign correspondent for many years. You lived in Moscow, Delhi, London. And recently you wrote very movingly about your father and his illness and how it affected your family, who if I understand correctly, you moved back to the United States to be closer to. I want to start by having you describe what specifically prompted that move and how your father's health deteriorated from there.

[Ellen Berry]

We had been in India for four years and in India you realize that almost everyone lives in a joint family, like a multi generational family. I really began to admire this arrangement and my parents were in their late 80s. They'd spent their lives in the Foreign service, moving every few years. At the time though, they were in a house in D.C. retired and we were looking for a way for them to make a transition into a new arrangement. So we came up with this plan to buy a two family house and the idea was that they would have some autonomy, live downstairs. My kids could have a period of time living with them. I sort of knew it was now or never because of their age and so we did it. So one week before the movers were supposed to come My dad had a fall. He fell hard. He hit his head on the floor. It was a hardwood floor. He lost consciousness. My mom was the only person with him, but she thought it was five minutes. It was obviously an extremely serious head injury, and for a few days it wasn't clear whether he was going to survive it. Once they were able to do a brain scan, they told us that he had a subarachnoid hemorrhage, like he had had a brain bleed. I remembered subarachnoid, because I used to call it under the spider. But I remember, like, two days afterwards when the nurse came in and he asked her for a newspaper and a cup of coffee. And that's how we knew that he was okay.

[Rachel Abrams]

So he was improving, healing?

[Ellen Berry]

Yeah, he was up and about, and it seemed like he might be recovering, but with time and especially with retrospect, it's now clear that this is the beginning of a sort of accelerated vascular dementia that ended up being the cause of his death four and a half years later.

[Rachel Abrams]

After the injury, how was he, like, just in terms of cognitive function, how was he. How did the injury affect his thinking, speaking. Just sort of everyday living?

[Ellen Berry]

Yeah. So he was in a rehab facility for a few weeks, and we were just kind of trying to figure out, like, when would he be okay to come home and what exactly were we dealing with? And we couldn't tell. It was right after his injury, so it wasn't clear. But some things began to emerge. He began to have what I would describe as bizarre but very interesting delusions. How so?

[Rachel Abrams]

Can you give us an example?

[Ellen Berry]

He told us that his roommate at the care facility was smuggling black caviar into the country. And somehow he believed that he had been wrapped into this scheme. He also reported to me that the nurses here are all kgb. And I said, how do you know? And he said, because they speak perfect English. Obviously proof, but also, more seriously, he didn't really know where he was. He would try to go into the wrong room.

[Priya Rajasetapati]

He.

[Ellen Berry]

He didn't know why he was in a rehab facility. He didn't understand why he couldn't leave. And he was more than before the injury. He was really impulsive. I think we had the idea that all this confusion was a function of being in the hospital and that once we got him home and settled, that it would resolve.

[Rachel Abrams]

So what did it look like when he got home? What was that like?

[Ellen Berry]

Well, I think we felt like we had just reached home base somehow that, you know, now he would sort of come to rest in a Place that was comfortable. They moved into the downstairs and put up, you know, their art from their house in Washington and really kind of recreated the house that they had just left. My mom started gardening and she started cooking for him. And they had two poodles. There were aspects in which his life was very similar to the routine he had before his injury. So he would get up and commit the first two hours of the day to reading the New York Times or walking the dogs. It seemed like things were kind of normal, but really from early days, we began to notice some behavior changes. Some of them were just absurd and sort of comical. He was really impulsive. The things he wanted were not all that different from the things he would have wanted in his old life. For example, my mom said she wanted

[Rachel Abrams]

a bird bath, like an actual bird bath to be put outside.

[Ellen Berry]

She wanted a birdbath. And one day we got a bird bath from China, and then the next day we got another bird bath from China. And we ended up getting seven bird baths, one after the other.

[Rachel Abrams]

Seven bird baths.

[Ellen Berry]

Incredibly, in a cascade of deliveries, we returned every single one, I guess, but one. We must have kept one. We got a delivery of, I think four or five laptops.

[Rachel Abrams]

Four or five laptops?

[Ellen Berry]

Four or five laptops. We had to return all of those too.

[Rachel Abrams]

These are things that presumably your father was ordering online when nobody was looking?

[Ellen Berry]

Yes. At one point I expressed the desire for a Japanese dwarf maple tree. And one night he just disappeared. He left the house at like 3 or 4 in the morning with the car and we called the police. And my husband, I don't really know how he knew immediately where to look for him. It was the dead of night and he drove out to a nursery which was, I don't know, probably 25 minute drive. And he pulled up outside this nursery and my dad was there alone, just waiting for the sun to rise. And he had smashed up the car. It wasn't terrible, but like, he shouldn't have been driving. And my husband went up to him. He was sitting outside this nursery. And my dad always knew what to say. He said, fancy meeting you here. But there was one change in particular that was for us, very difficult to handle. And that was that he thought he was in the wrong place. And he felt pretty much all the time that he had to leave.

[Rachel Abrams]

What do you mean?

[Ellen Berry]

You know that feeling when you think you might miss your plane? That kind of restless feeling? Yes, it was like he had that every day. He would say, well, we have to pack the car to go to drive down to Washington or I have to catch a flight. He said he had to catch a high line to Kyiv. He said he had to go to Philadelphia. He said he had to leave the next morning to take a water route to China, which from Massachusetts. Doesn't make a lot of sense.

[RBC Capital Markets Podcast Announcer]

No.

[Ellen Berry]

He said he had to go to Vienna to accept an award, the vote of Kirche. He had different ideas about where he was supposed to go, but the feeling was always the same, which is like that feeling of, if we don't get ready, we're gonna miss our connection.

[Rachel Abrams]

I take it that he didn't actually have to go to any of these places, but would he actually try to leave?

[Ellen Berry]

Yeah. What did he do? Yeah, I mean, if he didn't try, it wouldn't have been as much of a problem. So what he would do is he would pack suitcases, he all the pictures off the wall, and put them in the car. Once he picked up an entire decorated Christmas tree and put it in the car. Wow. And sometimes he would leave. Sometimes he left on foot. In the early days, before we took away the car keys, he left in the car. And so it became a kind of habit in our house that we would catch him as he was trying to leave, and we would try to redirect him. We would bring him inside, we would tell him whatever we had to tell him. Sometimes we'd just Dr. So that he had the feeling of movement. My husband, God bless him, sometimes took him to Logan airport and just let him walk into the terminal and then come back to the car.

[Rachel Abrams]

Just to be clear, when he is trying to leave and you are interacting with him, are you trying to convince him of where he is, that he doesn't actually have a place to go? Are you trying to reason with him and remind him that this is his home?

[Ellen Berry]

Yeah. Well, I mean, this went on for four years. So all of those things.

[Rachel Abrams]

And when you did try to redirect him in those situations, how would he respond?

[Ellen Berry]

I mean, he still had the same personality. He was incredibly stubborn, and he thought we were trying to hoodwink him. We would try to tell him he didn't have to go to the airport, and he didn't believe us. There were times when we were really skillful and inventive, and there were times when we were frustrated and desperate and angry that he didn't understand that, like, we had set up this whole arrangement for him. I remember one time, my husband, who is the one who did a lot of this redirecting, wrote a note that he stuck on the inside of the door that said, bob, you live here. Don't move. We love you. So that when he was leaving, he would somehow be reminded that this is where he belonged. Did that work? Not really. And in the end, we had to get a locksmith to come in and install locks on the insides of the doors just to make sure that he didn't leave during the night. Because no matter how many times we told him, he didn't seem to be able to remember that he had decided to move in with us, that we had bought this house together, and that this is where he was planning to live. So all of that, like, recent stuff that had happened leading up to the move, it was all gone. He couldn't access it if he couldn't

[Rachel Abrams]

remember things that were recent. Ellen, were there things that he could remember from farther back?

[Ellen Berry]

Yeah, it seemed like the farther back it was, the better he could remember.

[Rachel Abrams]

Oh, really?

[Ellen Berry]

There's a particular night that made me realize this. I could hear what was going on in their apartment from my bedroom. And I heard him downstairs. I don't know. It was the middle of the night, and I went downstairs in my pajamas, and he and my mother were sitting at the kitchen table, and he was crying. And I. I wasn't used to seeing him cry. He was a very controlled personality. And he was telling a story. She was standing behind him. She had her hands on his shoulders, and he was telling this story. When he was six years old, his family left Pittsburgh, where he'd been born, and they moved to an Air Force base in San Antonio. They took a train from Pittsburgh, changed trains in Chicago. He was leaving everything, but he was able to take one pet. The pet was a canary that he was carrying in a cage on the train. And they were in Chicago in the station, walking to catch their connection to Texas. And the bottom fell out of the cage, and the canary flew out into the. The station. And the canary just goes up into the upper reaches of this station. And he had to keep walking with an empty cage and get onto the next train without the canary.

[Rachel Abrams]

Did you have any idea what had prompted this?

[Ellen Berry]

No. And sort of beyond that, I knew his life story pretty well. He had written a memoir that he didn't publish, but I had read that story, wasn't in it. He liked to tell stories. That was not a story he had ever told me.

[Rachel Abrams]

Unlike the KGB nurses, unlike the roommate secretly smuggling caviar, you were able to recognize that this was, in fact, an intact memory.

[Ellen Berry]

Yeah. This was not an anecdote or a story. That he was telling us. It was a memory that he seemed to be reliving so painfully in real time in front of us while he sat at the table. I remember after having this conversation, I remember being just mystified. He seemed to have lost so much of his memory about his life. And yet this one thing, it was perfect. Like a bell jar. It was like perfectly preserved. And a lot of time would pass before I found out why that was.

[Rachel Abrams]

We'll be right back.

[Priya Rajasetapati]

Foreign.

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[Rachel Abrams]

So Ellen, it sounds like your father basically was reliving a memory of losing this canary when he was six years old. This is a story you had never heard before. What did you learn eventually about this memory that had seemingly resurfaced?

[Ellen Berry]

My dad died and about a year later I was covering my beat, which is mental health, and I opened my email and saw this press release come through. And this is pretty normal for me. I just scan them to see whether it's something that we should cover. But this particular press release really caught my attention. It was for a paper in nature neuroscience about the creation of memory. And almost immediately it made me think of that whole thing that we had been trying to manage with my father during those years. So I reached out to the scientist who had written the paper, Priya Rajasetapati, and we talked about her work. I interviewed her and at the end of the conversation I told her about my father, that he had a fall, that after the fall his memories were scrambled and that some of them seemed to bob to the surface in a way I couldn't understand. And she asked me if I had any scans of his brain.

[Rachel Abrams]

And presumably you did from his time being ill. We didn't.

[Ellen Berry]

But I began what would turn out to be kind of a prolonged process of getting ahold of the scans that were taken right after his fall.

[Rachel Abrams]

So that you could show them to her?

[Ellen Berry]

So I could show them to her.

[Rachel Abrams]

So what did she make of them when she saw them?

[Ellen Berry]

Well, we arranged to meet in her office at Rockefeller University, which is this beautiful old campus overlooking the East River. And I was very excited to have finally shown up with these scans. But she wasn't able to open them, she didn't have the software. So I ended up walking away empty handed. But a day or two later she sent me a text message and she said, I've been able to open them, there's something pretty interesting. And I remember getting this. I think I was in the office working on something else and just teared up because I couldn't believe that there was something to find in the scans. And she told me to come back the next day and that's what I did.

[Rachel Abrams]

And when you went back, what did she tell you?

[Ellen Berry]

So, I mean, do you look at the brains of people? You know, I have to assume not. No, actually I sat down and right

[Priya Rajasetapati]

away, and then here's the CT scan.

[Ellen Berry]

She was showing me cross sections of my father's brain.

[Priya Rajasetapati]

See this?

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Where?

[Ellen Berry]

There, this white thing.

[Priya Rajasetapati]

I'll show you a different view of it. This is kind of the biggest bleed that he has.

[Ellen Berry]

And she pointed out to me what looked like a star or like a burst of white which was deep in the brain.

[Rachel Abrams]

Boom, there it is.

[Priya Rajasetapati]

Yeah, there it is.

[Rachel Abrams]

And what was she pointing to exactly? What was she seeing?

[Ellen Berry]

What she had seen was the bleed that damaged his brain after he fel from the fall.

[Priya Rajasetapati]

These are immediate, the white bleeds are immediate.

[Ellen Berry]

The brain bleed had directly affected the hippocampus, which is this part of the brain that's known to be the kind of engine of memory that kind of takes in Stimulus from the outside world differentiates and records important stimulus as something that is going to be retained as a memory.

[Priya Rajasetapati]

For instance, here's the hippocampus on the other side.

[Ellen Berry]

You see this looks like a seahorse.

[Priya Rajasetapati]

Like a seahorse. And you see it on this side, and that's kind of where the bleed is. It's only on the right side.

[Ellen Berry]

His injury was on the right hippocampus, which is the part of the brain that organizes your sense of place and location. And, of course, that is exactly what we have been struggling with for four years, for sure. What the picture shows and what I experienced lines up that. Like, that the thing that he couldn't do is, like, we couldn't convince him that he was in the right house.

[Priya Rajasetapati]

Yeah.

[Rachel Abrams]

So this is, like, the first time it sounds like that you are really being given an explanation for what you experienced with your father. When he was disoriented, when he felt like he was not in the right place, when he was restless, when he was trying to leave.

[Ellen Berry]

Yeah, it was like a physiological, concrete explanation.

[Rachel Abrams]

Okay, so the hippocampus is damaged, but how does that help explain the canary story? Like, the older memories that seem to be undamaged?

[Ellen Berry]

So she told me that there are some memories that can be stored in more protected parts of the brain, like the prefrontal cortex, so that they stick around even if the hippocampus is really damaged.

[Rachel Abrams]

So why are some memories stored in one place and saved, and other memories are stored in another place and lost?

[Ellen Berry]

What you've taught me about the thalamus is the role that it plays in gating.

[Priya Rajasetapati]

Yes.

[Ellen Berry]

So what she has discovered is that there's an organ in the brain called the thalamus that seems to function as a gatekeeper.

[Priya Rajasetapati]

Our brains naturally say what's important. The canary is important. Meeting my wife was important. Important. And the thalamus gates it and transfers to cortex.

[Ellen Berry]

It sends these particularly salient memories, particularly important memories, into the more protected parts of the brain.

[Priya Rajasetapati]

And that's why he had these cortical memories that really were still so important to him.

[Rachel Abrams]

And how does the thalamus decide what goes where?

[Ellen Berry]

Well, that's what she's trying to figure out. The canary is a kind of traumatic memory. It's other memories, like Tonawanda. Like, that was like, a rewarding memory. But are you saying, like, we keep both of them?

[Priya Rajasetapati]

Yes.

[Ellen Berry]

She thinks that it has to do with what she called valence. The kind of intensity of the experience, whether it's negative or positive, it can

[Priya Rajasetapati]

be really Good or really bad. But if it's high on the valence spectrum of both, we can see them selected at the level of the thalamus. And so we have active projects going on in terms of how that's happening, but we don't know yet how it assigns that value, but it's very clear that it does.

[Ellen Berry]

And I think that happened.

[Rachel Abrams]

So, like the canary story, for instance, might have stayed, perhaps because it was something that really meant a lot to your father, really impacted him at a young age, Theoretically.

[Ellen Berry]

Exactly.

[Rachel Abrams]

What are the implications of all of this, her research, what she's learning?

[Ellen Berry]

I think it raises this sort of tantalizing possibility that maybe we could help people hold on to some memories that are just really essential to living.

[Priya Rajasetapati]

If you look at early stage Alzheimer's, they often come in and they still have some functioning.

[Apple Card Advertiser]

Right.

[Ellen Berry]

If you could somehow learn to manipulate that gatekeeping mechanism. What's happening in the thalamus?

[Priya Rajasetapati]

If you can go in and say, hey, there are weak things that are coming in, they're not able to be stabilized by the hippocampus itself. But if we can offload them very quickly, can we send them off?

[Ellen Berry]

You could move those memories out of the damaged parts of the brain into healthier, long term storage before they're lost.

[Priya Rajasetapati]

Even if half of it's gone, or 80% of it's gone. If 20%, 10% of our neurons are okay, yeah. And we're right there offloading things and stimulating this part of the brain to get things into the circuit. I think of that as a promising approach.

[Ellen Berry]

Does it feel to you like this is moving faster than it ever has? Like our understanding is.

[Priya Rajasetapati]

For me, it just feels like it's real and new. Those are the two things I feel most about.

[Rachel Abrams]

You mentioned the idea of saving memories that are essential. What memories are we talking about specifically?

[Ellen Berry]

I mean, recognizing your family, the people around you, recognizing the place where you are and knowing that you're home or that you're safe. The kinds of things that at the end of your life, you really want to hold onto.

[Rachel Abrams]

How did it feel, Ellen, to walk away from that meeting with at least some kind of theory about what your father had experienced at the end of his life?

[Ellen Berry]

So I remember walking away from that meeting, really sort of thrilled. It was so surprising that there was something so physiological that could kind of explain what we had been through during that time. And I remember calling my husband and telling him, the part of his brain that was injured in the fall, that was the part that creates memories about location and place. It just. It explains so much. And I asked, what are you thinking? And he just. He said it made him feel sad.

[Rachel Abrams]

Wait, why? Why did he feel sad?

[Ellen Berry]

Well, to understand this, you'd have to sort of understand the way our household functioned. I was working a lot, I was traveling a lot. And my husband was the one who, more often than not had to track down my dad when he wandered away. Had to find him on the side of the road in our neighborhood, talk him into getting in the car, tell him some kind of story about why he had to go home. He's the one that took him to the airport. And I think he just felt sad that for all this time, we didn't really understand that there was a permanent change, that something had changed about him, that we couldn't talk him out of it. We couldn't retrain him or teach him.

[Rachel Abrams]

You couldn't reason with him, convince him

[Ellen Berry]

where his home was, but also that, like no one had told us, you know, you're gonna spend the rest of his life trying to persuade him that he's home.

[Rachel Abrams]

Do you think if you had known any of this, it would have changed how you interacted with him?

[Ellen Berry]

I think it would have helped to know that we couldn't talk him out of. Would have helped to know, like, this is a one way change. It's not changing back. It would have helped to know he wasn't being stubborn or willful or impulsive, but that, you know, something had changed about his brain where he just couldn't compute. I think it would have helped us come to peace with the fact that he was a different person from before the fall. I don't know. Understanding what's happening in the brain doesn't mean that you can stop it or reverse it, but it may prepare you better for accompanying them to the end.

[Rachel Abrams]

Ellen, thanks so much.

[Ellen Berry]

Thank you.

[Rachel Abrams]

Today's episode was produced by Luke Van der Plug with help from Alex Baron and Tina Antolini. It was edited by Wendy Dore and engineered by Rowan Niemisto. Production assistance and fact checking by Dalia Haddad and contains music by Marian Lozano and Dan Powell. That's it for the Sunday Daily. I'm Rachel Abrams. See you tomorrow.

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