TERRY GROSS, host:
This is FRESH AIR. I'm Terry Gross.
You know the sensation of being so distracted you've forgotten where you're going or why? Or you're with a friend and you run into someone you know, but you can't remember her name, so you can't introduce her to your friend? Distraction and blanking out on names are just a couple of the brain issues that tend to get worse in middle age.
The changes that happen in the middle-aged brain, for better and worse - and yes, there are some improvements that come with middle age - is the subject of the new book "The Secret Life of the Grown-up Brain" by my guest, Barbara Strauch. She covers the latest scientific research about the middle-aged brain, and by middle age, she means 40 through 68. She's in her late 50s.
Strauch's new book is kind of a sequel to her book "The Primal Teen: What the New Discoveries about the Teenage Brain Tell Us about Our Kids." Strauch is health and medical science editor at the New York Times.
Barbara Strauch, welcome to FRESH AIR. What are some of the middle-aged brain issues you were experiencing that got you interested in the subject of the middle-aged brain?
Ms. BARBARA STRAUCH (Health and Science Editor, New York Times; Author): Ah, well, lots of them. For instance, as I reached middle age, I think, as all of us, we begin to have what we call senior moments or whatever, that I'd go downstairs to try to get paper towels. By the time I got there, I couldn't remember what I went down there for.
It was driving me crazy. You couldn't remember what I had for breakfast or the movie I saw last weekend. And, you know, we all have a lot going on in our lives, but I think there was kind of a qualitative difference in this in terms of, you know, things that I really normally would remember sort of vanished from my brain.
And I was concerned. And earlier, I had written a book on the teenage brain, and many of the people who had arranged me to talk about that were middle-aged, and they would say, too, you know, you really should write a book about my brain. I'm very concerned. You know, I can't remember anything.
They were middle-aged. So I began to think: What is going on? Where do those names go? What's - I mean, do they float up into the sky and are laughing at us? I mean, what is happening in middle age that makes our brains so forgetful? And forgetting whole episodes, really, which was kind of worrisome.
GROSS: That sense of vanishing is really scary.
Ms. STRAUCH: Yes.
(Soundbite of laughter)
GROSS: Feeling like there's a blank where a memory is supposed to be.
Ms. STRAUCH: Yeah, yeah. It is scary, and I think it makes us all worry. Many of us have watched our parents, you know, suffer from dementia and things, and I think we're kind of scared. You know, our parents aren't necessarily falling off the backs of tractors and dying or things like that.
We're watching many of them, you know, become older and suffer dementia of one form or another. And I think there's kind of a collective worry that maybe this name-forgetting, this kind of not knowing, you know, your train of thought is maybe we're on some sort of slide into dementia. And I think we're all a little bit worried.
GROSS: And what did you find? Do you think that that typical sense that memories are vanishing, you forgot you started boiling water after you started boiling it, that you can't remember the name of someone you know - is that part of the road to dementia, or is that separate?
Ms. STRAUCH: Well, what they've found, when I started looking into this now, for the very first time, scientists are actually looking at what actually happens in middle age, and they're sort of looking with brain scanners, and there are many more sophisticated studies out there now that started 40 years ago that actually followed the same people through their lives.
And what we have now as a species for the very first time is this long span of time, a long middle age, which has never actually existed on the planet before, and there's many researchers who are going in and looking at this for the very first time.
One told me it's like, you know, sort of studying nuclear physics because this is brand new for the species. And so we now have the results of long-term studies. We have brain-scanning. We have genetic analysis. And when I started looking into this, what I found out is that we have a whole new image of middle age. And yes, it includes some of this decline and forgetting names and things like that.
There's no question that there are declines in our brain. But what they're starting to do is sort of sort out what is normal aging, what is pathology and leading toward dementia. And they now know that dementia is not inevitable, and that basically this normal forgetting is part of normal aging, and in many ways, we can, if we keep ourselves healthy, actually improve our brains from middle age going on. And we can live, actually, throughout our lives with pretty sharp brains if we're lucky. So it's not necessarily inevitable that we are headed toward dementia, no.
GROSS: Well, you write that what surprised you is that the middle-aged brain is in some ways better than the younger brain, but let's get to that a little bit later.
Ms. STRAUCH: Yeah, right. Hard to believe.
GROSS: Let's start with what is so troublesome and kind of frightening to a lot of people, which is how easily distracted you can be, particularly in middle age, that - the idea that you'll start something, go to another room for a second, and then completely forget that you'd started something. Why is the brain more distracted in middle age?
Ms. STRAUCH: Yes. There's no question that I think, you know, it's not necessarily the only age - you know, teenagers are not sort of your example of mindfulness. We all know that. But what happens in middle age is it simply happens more often and in a degree, I think, that is more worrisome.
We will be boiling water. Someone will come to the door, and we'll forget we're boiling water. These thoughts sort of bounce out of our heads, and we are more easily distracted.
What is happening, they think, is that the brain can suddenly, as you age, fall into what they call sort of a default mode. This is kind of a daydreaming mode that - it's kind of an inner dialogue.
For instance, you'll be driving along and - this has happened to me. I know that, basically, you're driving along, and suddenly, you look up, and you think oh my goodness. I haven't been paying attention to the road at all. You've been thinking about, you know, brining the turkey for Thanksgiving or, you know, what you're going to do at work or whatever, and suddenly you realize you have not really been paying attention.
And what they think happens is as you age, you do fall into some kind of a daydreaming default mode more easily, and this default daydreaming mode is brand-new. They didn't know it existed in the brain before, and they're now studying it and trying to figure out how that happens.
And I - there are also some researchers, some very good brain scanners out in San Francisco who are watching this on a minute level. And what they find is that as brains age, the very first second that we try to pay attention to something, our brain's processing speed might be a little slower - that does decline as we age - and that we might miss a beat in the very first moment of focusing on something. And so we're a little bit off in terms of getting that memory of what we're doing or what we want to remember into our brains in a good, clear way.
So one thing they tell you is to focus very hard at the beginning of things so that you can sort of get past that moment where sometimes we are more distracted. There are things that happen in our brain. There's no question that there are some declines.
GROSS: Now this default mode, this daydreaming state of mind that you refer to, you say confirmation of its existence is considered one of the most important discoveries ever made about how brains operate and age. So is it a discrete place in the brain that's responsible for this default mode?
Ms. STRAUCH: It is, in a way. They can watch a brain, for instance, that should be on sort of using maybe the frontal cortex, which is right behind our foreheads and has grown very large in humans. This is the part of our brain that makes us most human and really keeps us on task and planning and paying attention, and they can watch, sometimes, people in brain scanners, for instance, when they're supposed to be using that part of the brain kind of fall into a lower part of the brain that is not in the frontal lobes at all and sort of hang out in this area that is not the area that you use to pay attention.
So that's what they're watching. They can see it physically happen in the brain, and they can see it happens more often with people as they age. And these are normal aging things that happen.
Obviously, there's a spectrum of people who do it more than others, but I think if we're all honest with ourselves, we realize that this does happen.
GROSS: So to sum up, you're saying that scientists have discovered that the middle-aged brain more easily slips into this default mode and isn't - and is what - not really concentrating on absorbing new information, paying attention, remembering what you're doing, that kind of stuff?
Ms. STRAUCH: That kind of stuff, yeah. And so there's no question that, you know, along the way, in our 40s or - actually, what happens in the brain from our 20s on is that the processing speed slows down. There's no question that we lose processing speed in our brains. That's - for instance, they test it with how fast can you tap your finger, or how fast can you remember, you know, words that start with D or whatever.
So they know that that processing speed slows down, and what's different is they used to think that that processing speed under - was underpinning every aspect of our brains, and so they really thought that since we saw such declines in that, that our brains inevitably were declining in all sorts of areas.
But what they now know is that the processing speed may affect certain functions of our brain, paying attention in the beginning, falling into the default mode, for instance, things like that. But in general, the other attributes of our brain, by middle age, are so vast and so much better than anybody ever thought, that we really - the processing speed and the declines that we see in middle age may not matter that much.
GROSS: So we talked a little bit about distraction in middle age. Let's talk a little bit about that sense of drawing a blank, that there's a blank where a memory used to be. You can't remember a name. You can't remember that you did something. You can't remember what you've read. You can't remember the title of the book that you can't remember that you read.
(Soundbite of laughter)
Ms. STRAUCH: Yes, exactly.
(Soundbite of laughter)
Ms. STRAUCH: What was that? What were we talking about?
GROSS: So what are some of the new scientific explanations for that sense of it vanished, that name vanished?
Ms. STRAUCH: Right. What they now know is that memory is not one thing, and as they look into memory, they find there's different parts of memory. For instance, as we age, it's very odd, but certain parts of our memory remain quite robust.
For instance, our autobiographical stuff. We know where we came from. We know -I know my brother's name is Ron. Things like that stay with us. Other things, like how to swing a tennis racket, how to ride a bike - habits, basically, washing our hands and things - do not go away.
So what's going on, then, with this other part of memory, which they actually call episodic memory or memory for things in context? For instance: Where did I have Thanksgiving last year? Was Cousin Harry there? You know, these episodes are what seems to be more problematic as we age.
So we keep that certain memories, and other parts of our memory seem to wane. Short-term memory, obviously, for names gets a little bit dicey along the way, and this episodic memory, you know, what did I have for breakfast, remembering what happened in context.
So that's an issue, but part of the good news is there's some scientists, Deborah Burke out in Pomona, for instance, who has dissected what happens, for instance, to names. She finds that the problem with names is basically not a storage issue. It's a retrieval issue.
In other words, those names are not really lost. They're just kind of temporarily misplaced. And she has done lots of studies, for instance, that show - well, if you're trying to remember a name, for instance Brad Pitt. If you can't, later on, if you're given a hint and you don't know it's coming at you and you don't know it's connected to what you're trying to remember - for instance someone says cherry pit to you, suddenly that name Brad Pitt will pop up into your brain.
So it's not lost. What it is is just basically a difference - a problem with retrieval. And what she finds is that with names, in particular, that the way that they're stored in our brain, the information about the sound of the name and the information about what that name is, is kind of weak.
There's one connection. It weakens with age. It weakens with not use, you know, un-use.
GROSS: You say that the word and the meaning of the word are stored in separate places. And those two - sound is...
Ms. STRAUCH: Yes, the sound of the word.
GROSS: The sound of the word, yeah.
Ms. STRAUCH: So, like, the sound of the name and what that name - information about that name she finds are stored in different places, and the link between them basically can decline. And if you don't - in other words, if you haven't seen somebody in a while, those are the kinds of names - or used their names in a while, those are the kinds of names that go.
Also, the names are very arbitrary. For instance, we might remember one of the seven dwarfs is Grumpy because he is grumpy, but it might be harder to remember Peter Pan, for instance, because that name doesn't tell you anything.
I have never forgotten the name of my childhood dentist. His name was Dr. Smiley(ph). I think he's the only name that I remember from my childhood in terms of medical professionals. So because it is linked, it wasn't quite so arbitrary, that's in my brain forever.
And so what she finds is, though, that we can retrieve those names. They pop up. That's why, for instance, we can't remember a name, and then, you know, two days later, you think oh, Brad Pitt, or oh, you know, Terry Gross. I remember her. And the name will pop up into your head.
They even find this, for instance, like, internal sounds. Say you're trying to remember the name Velcro, and you can't for the life of you remember this word Velcro, that stuff that sticks things together and we use on shoes and things. What's the name of it? So if you can't bring that name to mind, later on if you hear a word that is even internally similar - for instance pellet, with an E-L in there - sometimes even that will be enough to prompt your brain to go get that Velcro name, and there it is.
GROSS: Is it all words that are stored in separate places from the meaning of the word, or is it just, like, proper nouns? You know, names, places.
Ms. STRAUCH: Proper nouns seem to be problem, again, because she thinks they're so arbitrary. For instance, if you - there's a guy named Bob, and he's a baker. You can see him on the street, and you will remember he's a baker, but you won't remember his name is Bob. And the reason for that is because there are so many other things that can prompt you to get to the word baker.
For instance, you can think white hat. You can think flour. You can think -there's other places for that information to be stored and linked in your brain, but the name is very arbitrary - not that useful, not connected, really, to anything. So it's stored in fewer places.
They find, for instance, if you want to remember somebody's name, if you can add places in your brain for that name to be linked to - for instance, if you're trying to remember, you know, Joe, and you look at him and he has, like, a big nose or bushy eyebrows. If you think when you meet Joe, Joe bushy eyebrows, that will store some of that information in a place in your brain that will help you, when you're trying to remember his name, retrieve it. That means there's more of as they call a neural footprint in your brain.
GROSS: You mention a little memory trick that you and some of your friends have tried that I use sometimes, too. Sometimes it works, sometimes it doesn't. But if you can't remember a name, but you know that it's in your brain someplace, if you just run through the alphabet and say A, no, B, no, C, no, D - yeah, it's David. You know...
Ms. STRAUCH: Right, exactly. That's amazing.
GROSS: How much success do you have with that, and what's the explanation for the success?
Ms. STRAUCH: Well, again, the explanation is that sound of the word. For instance, once you get to B, B may prompt the word - the sound may help you, just as you hear cherry pit might prompt you to remember Brad Pitt's name, for instance, the sound may be a link enough to help you retrieve that name.
So that's why we're all kind of walking along and silently going through the alphabet, and it may take us a little bit longer, and we might look a little silly, but, you know, you'd be surprised how many people are - you know, when I talk to them, they are already using this little trick, which I think is amazing.
So there's other tricks you can do. For instance, they find that if you're trying to remember to take medicine or do something later in the day, if you imagine yourself doing it, actually picture yourself doing it, again, it will create a bigger neural footprint in your brain, more ways for you to remember that.
So that's kind of a couple things we can do to try to, you know, help ourselves out through this period.
GROSS: What are - before we get to some of the good news about the middle-aged brain, what are some of the other parts of the middle-aged brain that do degrade?
Ms. STRAUCH: Well, they think that - the people who have looked at this brain cell by brain cell think that our brains do shrink maybe two percent per decade, and that's really the brain branches that are coming off the brain cells. There's some decline in some neurotransmitters like dopamine that help us become alert.
There's no question that they see some decline, but the main thing about what they see when they actually look at the brain, brain cell by brain cell, is that the old idea that we lost 30 percent of our actual brain cells as we aged, which has been sort of scientific dogma for decades, is not true.
In fact, as we age, if we're healthy, we keep our brain cells. And that really has been the huge finding that has created a great deal of not, you know, sort of rah-rah aging, but actual fundamental shift in how we think about how our brains age and actually much more optimism because of that finding.
GROSS: What is this shift in thinking about the middle-aged brain that that finding has - is responsible for?
Ms. STRAUCH: Well, I think they think that - what they find is if we can keep our brain cells, that means that there's all sorts of ways, then, that with drugs or with eating or exercise or things, there are actual things that we can do to keep them running well.
So if the declines in processing speed and this slight shrinkage of our brains is taking place, what we also find is that the brain cells are in pretty good shape. We have enough now what they call pristine agers who age, and their memories stay intact, they are sharp for many, many years.
So we know it's possible. There's enough study now of people who have successfully aged through many years, and they've studied them. They now know sort of what's going on. They can separate pathology from what is normal aging, and there's much more encouragement. As I said, it's not just, you know, let's get old and be happy. It really is fundamental science, that they're watching actual brains age, and they're much more encouraged about what's going on.
GROSS: Are there processes that improve in the middle-aged brain?
Ms. STRAUCH: Yes. I think the most shocking thing I found was there's a woman named Sherry Willis who's done this Seattle longitudinal study, studying again, the same people, you know, thousands of them as they've aged, and she now has 50 years of data. And what she finds is that in middle age, which the modern middle age is now, you know, remember, at the turn of the century, our life spans were 48, by - on average. Now it's close to 80. So we now have this long span of time in the middle that really is brand new and we now have, now, science based on that brand new span of time.
What's going on? And what they're finding is that, for instance, there's whole areas where cognitive function actually is better during that span of time, from 40 to mid-60s, than it was when we were in our 20s, which I think is shocking to almost everybody that I mention it to and it was certainly shocking to myself. We think we're sort of the smartest in college or graduate school or whatever, and when they do the tests they find that's not true in many areas, including reasoning, inductive reasoning - we are better than we were in our 20s. And there's a whole host of areas where they're finding that we actually improve in middle age, over our, you know, our 20-something selves, and it's extremely encouraging. We are better at getting the gist of arguments.
When you're younger, you may, I mean this is a very simple example but, you may be better at remembering a list of fruit: bananas, oranges, whatever, grapes. But when you're older, as you get older, you're better at recognizing categories. Oh, those are all fruit. Or oh, those are all vegetables. And we're much better at sizing up situations. They find that we're better at things like making financial decisions. It reaches a peak in our 60s. Social expertise, in other words, judging whether someone's a crook or not a crook, also improves and peaks in middle age.
There's a whole bunch of stuff that we're sort of trained to think that our brains actually decline and that we get depressed and things, and on the contrary, our brains are functioning probably at their best in this new modern age - modern middle age.
GROSS: In that category that you're talking about.
(Soundbite of laughter)
Ms. STRAUCH: Yeah.
GROSS: Not in everything.
Ms. STRAUCH: No. No.
GROSS: But in that sense of sizing things up and analyzing.
Ms. STRAUCH: Yes. Yes.
GROSS: And you mentioned that there's, you know, a, I guess a physiological explanation for it. It's called bilaterization, that middle-aged people are better able to use two sides of their brain instead of one when thinking through a problem. Would you explain?
Ms. STRAUCH: Yes. Bilaterization, a big word that has been quite controversial, actually, because again, when they started looking inside the brains of actual people. When you're younger you will use one side of your brain to remember something or to learn something and another side of your brain - we're talking about the frontal cortex again, behind our foreheads, this human part of our brains.
When you're younger you use one side of your brain to learn something and another side of the brain to recall it. And as you age, they watched people use both sides of their brain for both tasks. And originally, they thought uh-oh, this must mean bad things. It must mean that there's some deficit somewhere, and these people, they're really trying to figure it out. And there was some concern because people with Alzheimer's will use sometimes more parts of their brain to try to do simple tasks that they could use with one part of their brain before.
But what they're finding is, the people who use as they age, two parts of their brain rather than one to do a task that they used to be able to do with one, are really the people who are functioning the best in terms of cognitive function.
GROSS: Can you explain which two parts of the brain we're using? I mean, one of them is the frontal cortex, which I don't know much about.
Ms. STRAUCH: Well, the frontal cortex is right behind our forehead and it is the part of the brain that, in humans, has gotten enormous compared to, you know, our closest relatives on family trees - chimpanzees or whatever that share 99 percent of our DNA. But if you actually look at the frontal cortex of a chimpanzee and look at the one of human, the human frontal cortex is comparatively enormous.
And this is the part of the brain that is developing as we're teenagers and probably finishes developing at some level when we're 25. And this is the part of the brain that helps us plan ahead, that see the consequences of actions. And this is the part of the brain that solves problems, makes us most human, really. And so we have a couple things going on when we're using two parts of our brain.
If it is something that calls for our frontal cortex to do the tasks that we want to do, then you'll see, as you age, people calling on two parts. We have two sides to our brain - right and left - and if they call on two parts of their frontal cortex to do a task, they can usually perform it better. If it's something that they usually don't need their frontal cortex for, you'll find that people who are really cognitively better than others will go in and reach for that frontal cortex to help them do whatever they need to do.
And they think that basically, the people who are used to reaching up and getting some of that high-power brain juice, really, they find correlations with education. The higher-educated people are better at doing that. They find people who maybe have more efficient brains, through genetics or whatever, are better at doing that. And what they're trying now to do, actually, is teach people to use two parts of their brain to call on their frontal cortex more. And that's why you get all these efforts to try to push the brain - as you get older - to try and make it work really hard.
And what they're trying to do is get you to use more of your brain and keep using more of your brain, so that your brain doesn't get into a rut and go fallow, or call on that frontal cortex more so those pathways are clear and you have it there when you need it.
GROSS: How can you consciously call on your frontal cortex more?
Ms. STRAUCH: Right.
(Soundbite of laughter)
Ms. STRAUCH: Hello! Frontal cortex? I think it really has to do with patterns of your brain. And what you really need to do is keep pushing your brain. It's not a conscious thing. I think that if we try to focus really hard on something, that's calling on our frontal cortex. If we learn something new, they say foreign languages.
Something that one professor at Columbia who has studied adult learning through the years says what's good is even talking to people who disagree with us. Creating in your brain what he calls a disorienting dilemma or kind of shaking up the cognitive egg. We have to present our brains with things that make it wake up, make it pay attention, make it work really, really hard. And it can have an impact in terms of just presenting your brain with, not just new information and not just retrieving information, you know, like with crossword puzzles, but actually getting out there and letting your brain confront things that are different.
GROSS: And make an argument to synthesize the thoughts you have and...
Ms. STRAUCH: Yeah.
GROSS: ...put it together in defense or an argument against an idea. That too?
Ms. STRAUCH: Yeah. I think it sharpens your brain. I find that, you know, if I listen to people who disagree with me or something, I find it sharpens my own thinking. You know, so it kind of makes sense. I think we all know this is kind of going on but we just never really paid attention to it and the scientists never really broke it apart to, you know, try to figure out what was actually going on.
GROSS: There's a whole industry now, of courses teaching memory techniques, of foods that are supposed to like enhance your thinking and memory capacity. And you've looked at this new industry that's growing up. Is there any proof behind any of the products, whether they're food or memory devices, that are being marketed now?
Ms. STRAUCH: Not much. No.
(Soundbite of laughter)
Ms. STRAUCH: This field is still just beginning. Most of the stuff that's out there is, while harmless, also not scientifically proven to really work. There's only one, I think, of this new brain testing - brain challenging things that have actually been tested in a scientific way and they did find it worked. That one was called Brain Fitness and they actually did a scientific study of that and found that that system, which is extremely rigorous, really makes your brain work hard.
GROSS: What's the system?
Ms. STRAUCH: It's a system that uses all sorts of things. For instance, they use sound like mat, pat, sat, and you listen to these and you have to keep distinguishing between the fine-tuned differences between the sounds, for instance. So again, it's training your brain to focus at the beginning, fine-tuning it and push it really, really hard.
GROSS: In your book you mention that exercise and oxygen can be helpful for memory.
Ms. STRAUCH: Yes. If there's a star in aging brain research, it is probably exercise. The best data is with exercise and across the board they find that if the brain needs anything, it is very much like the heart and it needs blood. It needs to circulate - the blood needs to be circulated. It needs oxygen. And so when they do the studies, from rats to humans, about vigorous exercise, they find that it improves cognitive function across the board. And they're finding now, as they look inside brains, it creates new baby brain cells. Something they didn't...
Ms. STRAUCH: Yes. Something they didn't think happened in the grown-up brain at all. So you get better. You get bigger brain volume if you exercise, and it seems to last. So there's no question that, sadly, exercise works in terms of keeping your brain in better shape. So that one is studied probably the best out of all the things you can do.
GROSS: When we say exercise, what are we talking about? Does it have to be like lifting heavy weights and, you know, doing all the machine stuff in the gym? Are we talking about walking every day? What are we talking about?
Ms. STRAUCH: Well, some of the studies - Art Kramer, University of Illinois, has found that people who simply walked around a track three times a week, you know, at a certain pace were better off than others. Walking, anything aerobic is considered quite good. You can't - it's probably best not to sort of take a stroll, but actually get your heart pumping. That's really what you want. Just as you were thinking about what do I need to do for my heart, think about the fact that you should do that also for your brain.
GROSS: So do you feel like there are social implications of what you learned about the middle-aged brain?
Ms. STRAUCH: Yeah. And I think that, you know, we've just gone through this recession - maybe we're still in it - where we watched a lot of people, in particular, older people lose their jobs. These are people really in the prime of their lives. And we know from studies that there's a great deal of age discrimination in hiring.
And I think when you learn this stuff it just makes you kind of sad, that our society is still setup for a lifespan that ended at 60. And many people are vigorous at 60, vigorous at 70, vigorous at 80 and we're sending them home and telling them they're not part of our society anymore. And I think it's set up backwards.
We really have to adjust to our lifespan and we have not yet. And even in my own company, I watched people who were 70 - the old days, you retired at 70, at 60, and that was considered what you're supposed to do. We watch people retire at 70 and they're still vigorous and maybe that was too early too. So, but the world is not set up to appreciate, I think, this middle-aged brain that we have.
GROSS: Barbara Strauch, thank you so much for talking with us.
Ms. STRAUCH: Oh, thank you.
GROSS: Barbara Strauch is the author of the new book "The Secret Life of the Grown-Up Brain." She's health and medical science editor at the New York Times.
You can find a list of brain exercises and read a chapter from Strauch's new book on our Web site freshair.npr.org.
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