
Dr. Charan Ranganath
12/16/2025 | 27m 45sVideo has Closed Captions
Dr. Charan Ranganath dives into the fascinating world of memory & enhancing memory retention.
Dr. Charan Ranganath is a renowned expert in neuroscience and author. They delve into the fascinating world of memory, discussing how memories shape our identity, guide our choices, and enrich our experiences. Dr. Ranganath shares insights on enhancing memory retention, the impact of emotions on what we remember, and practical tips for keeping our minds sharp throughout life.
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The School of Greatness with Lewis Howes is presented by your local public television station.
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Dr. Charan Ranganath
12/16/2025 | 27m 45sVideo has Closed Captions
Dr. Charan Ranganath is a renowned expert in neuroscience and author. They delve into the fascinating world of memory, discussing how memories shape our identity, guide our choices, and enrich our experiences. Dr. Ranganath shares insights on enhancing memory retention, the impact of emotions on what we remember, and practical tips for keeping our minds sharp throughout life.
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Learn Moreabout PBS online sponsorship>> Hi, I'm Lewis Howes, "New York Times" best-selling author and entrepreneur.
And welcome to the "School of Greatness," where we interview the most influential minds in the world to inspire you to live your best life today.
And today, I'm joined by the world renowned Dr.
Charan Ranganath, an expert in neuroscience and an author, and we dive into the fascinating world of memory, discussing how memories shape our identity, guide our choices, and enrich our experiences.
Dr.
Ranganath shares insights on enhancing memory retention, the impact of emotions of what we remember, and practical tips for keeping our minds sharp throughout life.
The conversation also touches on the power of moods to affect memory, the importance of context in recalling memories, and how to use mental time travel to transform negative memories into meaningful ones.
And I'm so glad that you're here today.
Now let's dive in and let the class begin.
♪♪ ♪♪ The first thing I wanted to start with is a stat that I saw online, and I don't know if this is 100% accurate or not, but according to the National Science Foundation, an average person has about 12,000 to 60,000 thoughts per day, and of those, 80% are negative and 95% are repetitive thoughts.
I don't know how accurate that is, but you say that memories shape our identity.
On this show, I'm all about empowering people to have the tools and the strategies to enhance their identity, because I believe identity dictates the quality of our life.
It's one of the key factors.
When we have a negative identity or an identity that is more suffering status or suffering states, we tend to suffer in our life.
When we have a more empowering identity of ourselves, we tend to have a more abundant life.
And my question to you is, how do we use our memories to shape our identities so that we create more abundance rather than have more suffering?
>> That's a great question.
And what I'll tell you is, is that the key to answering this question is that you got to understand that your memories are selective.
And the memories that we find depend on how we're searching.
Right?
So imagine you have a particular lens, like have you ever heard the phrase, like, you view the world with rose-colored glasses?
>> Yes.
>> Right.
And, so, that affects the colors that you're going to see, right?
And likewise, when we're searching for memories, we have a mood.
We have an emotional state.
We have a context, this inner landscape that is permeating our thoughts.
And that's going to affect what we can find.
And we used to actually do -- It was -- I mean, my first study that I talk about in my book was when I was doing depression research, actually, not memory research.
And what we used to do was to get people, we would play this sad music and then ask people to recall sad memories from their life.
Music made it easier to recall sad memories from their life, and the more -- when they recalled those sad memories, they felt terrible.
>> Interesting.
>> And then we had to get them out of it.
And that was a whole part of the thing.
So it wasn't unethical.
But the interesting part of that is the power of our moods to affect our ability to mine the past, and then the memories that we pull up, the power of that, to change the way we look in the present.
Right?
So the cool part of it is, though, you can -- if you try, you can go in the opposite direction.
You can say, let me think about a time, even though I know I'm going to bomb this interview and I'm going to -- Lewis is going to walk out of here and say, like, "God, this is a school of boringness."
You know, whatever, right?
Then I go like, no, I remember I had this great interview the other day, and I just have to bring that out of myself.
And once I remember that and I mentally time travel back to that moment, I can become a little bit of that person.
And people have shown you can become more altruistic if you do this.
You could become more sad if you pull a sad memory, become happier if you pull up the happy memories.
And it all depends.
And I think it's like everybody can kind of relate to this, right?
Because it's like you're having a fight with someone who you love.
You can think of nothing but all of the times that they've made you mad.
But now, a week later, you've made up.
Everything's great.
You can't even remember what you fought about.
Right?
So it's... >> Interesting.
>> This weird trick that we have, and I think the thing that people need to keep in mind is you are going to have a biased sampling of your past.
You can't remember everything, and what you pull up will be reflective of how you feel in the moment.
>> Really?
So if you're feeling good in the moment, you'll think of more positive memories?
>> That's exactly right.
>> And if you're feeling negative or depressed or anxious or stressed in the moment, you'll think of more negative memories from the past?
>> That's right.
And not just that.
Not just that, but when I'm feeling negative and depressed, I will tell the story of these past events in a more negative way.
>> In a more dramatic, negative way.
>> Yeah.
And if I'm in a positive state, I'll actually remember myself better than I might have really been.
And I'll remember things of having been better than they really were.
>> How much of our memories are accurate?
>> I like to say that memory is not photographic.
It's like a painting.
And what I mean by that is, you know, I'm trying to make a painting of you now and imagine I have a decent bit of artistic talent.
I'm more of a musician than a painter.
But go with me on this, right?
So I started painting your picture.
I'm going to get some parts completely right, like the color of your shirt, the color of your eyes, and so forth, the shape of your head.
But it's not gonna be perfect.
I'll make some mistakes.
I'll also leave some things out that I might not have paid attention to, and there will be some parts of the painting that are not really right or wrong, but they're more my interpretation, my perspective that I'm bringing to this piece of art.
And that is how I want people to think of memories.
Not in true or false, but a construction.
And just like if you go back to those old Renaissance paintings when they're poor, they have to redo paintings over the same canvas.
That's what happens with our memories.
When we pull up a past memory, we actually can change the memory, and it opens up the box again so that we can sometimes strengthen it and make it easier to access.
But you can also end up messing with it and create all sorts of errors in the memory from the time of remembering.
>> Now you're getting me into a fascinating thought process here.
When we -- I truly believe that the energy we have in the present will support us in making either conscious or unconscious decisions, empowering or disempowering decisions, and decide whether we show up with a good energy towards others or a negative energy towards others, based on the energy we have in the present.
What I'm hearing you say is, when we're time traveling constantly into the past and remembering things in a negative way, it's going to make us feel more negative, as well.
But also, if we're in a negative state to start with, we're going to be thinking about negative things from the past and our identity and why we're not good enough or all these different things.
My question is, how can we use mental time travel to reverse a memory from a negative one to a meaningful one, to support us in the present so that we make better decisions now and in our future?
>> That is the big question.
>> Let's go.
>> So we've got -- I give you 100 answers, but I'll give you like the shortest version, which is to keep in mind that that moment of mental time travel, when I recall something, or I hear a song, and it just brings me back to my childhood and I just flash back to, like, I don't know, the summer of 1984 or whatever.
I'm like 13 years old, let's say, it's not high school.
Junior high.
But go with me on this, right?
So I flash back to this period, terrible time in my life.
I'm feeling bad.
But then, I keep in mind that that sense of mental time travel is just a few bits and pieces.
It's a set of fragments, and then I'm making a narrative out of it.
I'm making a story out of it.
And that story is going to be shaped by my beliefs, right?
You know, I'm not going to construct a story about things that were impossible that just could never have happened, right?
That pigs are flying around or whatever, unless I'm at a Pink Floyd concert or something.
But I'm not going to construct all these things that couldn't have happened.
So we impose our beliefs and our knowledge in the present, right?
So if you go into this with the sense that I'm a failure or nobody likes me, you can certainly find that, find evidence for that in this memory.
>> From your memories.
>> Yeah.
And you can build that story, but you can also find things that are inconsistent with that.
And that was the big part -- I mean, that's why therapy, when I was doing -- I only spent a few years doing clinical work in my graduate training.
It was like six years, but it just dramatically influenced my way of thinking about things.
>> Therapy work.
>> Therapy work because it's all about sharing memories.
>> Interesting.
>> And no matter what we were doing, what people -- I had somebody, my first patient came in with a driving phobia, but even after he was okay to drive, it wasn't really until we processed this big, big memory of his that we really made progress.
But it's not about just recalling some traumatic memory because you can wallow in these memories and feel worse, right?
It's about being able to see it from a different perspective, to look at the same event, but ask, instead of going with your beliefs, challenging your beliefs, right?
So in science, Adam Grant talks about this, right?
It's like you try to find the things that disconfirm your hypothesis.
And that's what we do in science.
And, so, you can find that in memory if you look.
>> But if someone is so wrapped into a self-loathing identity based on a story they keep telling themselves, uh, this failure I had, this mistake I made, you know, this person abandoned me or treated me poorly, or I did something horrible that is unforgivable and I'm so ashamed of what I did.
And you live in that story and that self belief and identity, and you're like, all the evidence is there.
I did this thing, or this person did this to me, and it was horrible and wrong, and no one should have to experience this.
>> Yeah.
>> How does someone shift the story so that they don't feel stuck in the past of traumatic memories, but they can distance themselves and see themselves from a distance, from afar, without them feeling the pain, but actually remove themselves and look at the situation and start to change the story for themselves.
How do we start to do this practically?
Is there any strategies or process that we can actually do?
>> Well, it's really hard, and I don't -- I never want to tell, because every time I talk about memory, like four out of five people will say, "Oh, you know, I have such a terrible memory," or, "This is really reassuring.
I've been worrying about my memory."
One out of five will say, "How can I forget something?"
So there's a lot of people you're talking to with this question.
And I never -- I've -- When I talk to people face to face, it's always -- it's hard because you know, people will say, "That's easy for you to say."
And I agree.
It is.
But not that I don't have my own horrible memories that I get stuck in, right?
But I think one key that you can try to do is context can be very important because context is a big cue for memory.
So, for instance, when you go back to your childhood home, you would probably recall information from your childhood that you wouldn't recall in your house, right?
So maybe you can keep your environment one that has reminders of things that actually would be countering these beliefs, right?
So, like, I did this -- I mean, and this is not at all like a humblebrag.
It's just like -- But I got interviewed by "The New York Times" for "The New York Times Magazine."
So my wife took the pages from it and got it framed professionally.
And, so, it's on a wall in our hallway.
And I was thinking to myself, God, people would probably walk by to the bathroom and say, "This guy's such a jerk," or something.
>> So much into his ego or something.
>> Yeah, exactly.
But then, I was thinking it would be -- that's a really good reminder that, when I'm feeling down, hey, some people thought that what I did was interesting, and it counters -- And I can remember a specific event.
That is key.
>> What do you mean, a specific event?
>> Well, I can remember being interviewed by him and actually talking to him on Zoom and, uh, that whole experience and connecting with this person who I've never met before, who's interviewed -- Like he just interviewed Bono and Arnold Schwarzenegger.
And he's talking to me, right?
>> Wow.
>> And that feeling of being engaged and connecting with the person, which you don't always get, right?
And it's like -- And that happened to me in this one moment.
And, so, having these reminders, I think, can be very potent.
And likewise, you can surround yourself with negative reminders.
I talk about how addicts, when they're going to the same places and they're hanging out with the same people, those are triggers for memories that will literally activate the goal of getting drugs or alcohol, right?
>> Interesting.
It's almost like evidence of proof or belief in yourself by creating an environment with different reminders to support you that, hey, yeah, someone was interested in me, or I did something good, or all that hard work did pay off.
>> Yeah.
>> As opposed to having nothing to remind yourself of all the good that you've done.
I have a kind of similar feeling like that.
Like, I have some stuff hanging up in my office, and I'm always like -- some stuff I've taken down because I'm like, ah, is it too much about me?
Is it too much like look at my success in front -- You know, it feels kind of awkward sometimes.
>> Yeah.
>> Like, I literally have, you know, a cover of me on "Success" magazine, and I took it down and I put it on the ground because I was just like, just too much of me.
You know, it's like, is it too much, you know?
So I think there's a balance there to be like, make sure you're not look at me, how great I am all the time.
>> Well, a lot of people have that bias.
On average, people tend to be -- remember themselves more positively than they really were, actually.
>> Is that a bad thing, or is it a good thing?
>> It can be a bad thing, but it can also be a good thing.
I mean, there's nothing wrong with feeling good about yourself and having optimism.
And as people get older, they become, on average, more optimistic.
>> Really?
>> Yeah.
And they remember themselves in their past more positively.
>> Why is that?
>> We don't know.
My colleague, Mara Mather at USC, studies this, and she'd been pondering this for a long time.
And she has this idea about the way different chemicals in our brain change as we get older, causes these tweaks in brain systems that bias us more towards positive information.
I have yet to read the paper in depth sufficiently.
It came out pretty recently, and so I need to read the paper in depth to give you more.
But there are these changes that happen.
And I think one thing I'll also say is, as you get older, the brain changes in ways that make it so that it's less about you.
The prefrontal cortex -- >> It's less about survival in the beginning days, I guess.
Right?
Like, how do I survive?
And I don't know how to defend myself because I need others to help me.
>> That's right.
That's right.
It becomes more about like -- So there's an area of the brain called the prefrontal cortex that I talk a lot about in my book.
And it's so important for memory because it's what allows us to say, hey, this is my goal, and based on this goal, here's what I'm going to do.
As opposed to saying, well, this is what's in front of me.
Based on what's in front of me, I'm going to do this.
Right?
Those are two different things.
And, so, somebody with frontal damage might know what they want to do, but they can't use that knowledge to guide what they actually do.
And as we get older, the frontal cortex starts to decline in its function.
We become a little bit more -- It becomes harder to inhibit ourselves, but we're also a little bit slower when we have to do effortful things like searching for memories and so forth.
And you might ask, well, why is it we spend such a huge chunk of our life -- I mean, it starts after 30, believe it or not.
So why do we spend a huge chunk of our lives with the frontal cortex as declining in function.
And eventually I came to the realization that, well, you need that when you're in your 20s to 30s because you're in prime parenting years, and it's about keeping track of the big picture so that your kid, who has an immature prefrontal cortex, can play and explore and learn.
And you have to be thinking about the future, and you have to be thinking about this little nuclear family's future and going out and foraging and hunting, whatever it is.
Right?
But now you -- >> Providing and protecting.
>> Yeah.
Now you become older.
You're not having kids anymore.
It's not about you anymore because you're biologically just the likelihood is going down, especially for women past a certain age.
Right?
You get menopause.
So now it becomes about the collective, and really your kin especially, but the collective.
And if you look at most of human history, older adults were occupying very high positions and very engaged with younger people and passing on traditions of culture and language and so forth.
And I talk about this at the end of the book as one of the coolest discoveries that I'd made while writing the book was another -- There's not a whole lot of species that live long enough, let's say, to get menopause or long enough so that they're infertile for a large chunk of their life.
But another one is orcas.
>> Mm.
>> And orcas, if you look at a pod of orcas, who do you think leads the pod?
>> Between like men and women, or youth and old?
>> Anything.
Take a guess.
Throw it out.
>> Oh, my gosh.
Um... >> Okay, I'll spare you.
>> Yeah.
>> Postmenopausal females.
>> Really?
>> They're the ones who lead the pod.
>> Why?
>> Because they have the knowledge of the culture that they pass on.
And that's at least from the -- Now, I'm not a marine biologist, but from the readings, I kind of went down this little rabbit hole.
And from the readings that I did, it was that essentially they're teaching everyone in the pod about the language and about the culture and so forth, and that really rings true for me because I look back at my Indian family, and that was the way of thinking, that it's like the grandparents were really the ones who were playing this big part in their children's lives.
>> Wow.
>> I had much less of that because my parents were in India when I was growing up.
So I kind of missed out on that.
I had more of an American-style childhood.
>> This is a question I ask everyone towards the end of our conversations.
It's a hypothetical question.
It's called the Three Truths.
So I'd like you to imagine.
Again, we're talking about imagination.
So I'd like you to imagine the last day on Earth for you.
But you get to live as long as you want to live.
And on the last day, you get to leave behind three lessons or three things from everything you've learned in life, whether it be from career, personal, professional, whatever it might be, spiritual.
You get to share three final truths and this is all we have to remember you by.
What would it be those three truths?
>> Number one is just kind of a life lesson that I've learned, which is sometimes the worst thing that can happen to you is to get what you want, when you want it.
>> Mm-hmm.
>> And I've learned this so many times because I've had times where I wanted to get into this particular grad school, I wanted to get this particular job, I wanted to have whatever it was when I wanted it.
And it turned out that I didn't get it and some other door opened up that was far better than anything that I had anticipated or imagined.
Right?
So we've been talking about imagining this abundant future, but let's face it, the world is endless possibilities, right?
And, so, sometimes I think it's like the world hits you in the face, but it points you in a particular direction when it does.
And, so, I think that's been something -- I never, ever would have thought I would become a scientist.
>> Really?
>> Never.
Yeah, yeah.
Never.
I mean, it was like, to me, science was just a bunch of formulas and laws and rules, and I don't like laws.
I don't like rules.
So it was a -- Yeah, but it just kind of happened.
And it happened through a series of random coincidences and things that opened me up to a lot of the world that I never would have thought of, you know.
>> Wow.
Random coincidences or purposeful synchronicities?
However you want to look at it.
>> However you want to look at it, but that's the thing.
It's like you can find meaning in these things after the fact, right?
>> Yes.
>> And I guess that's the second thing I would say is cultivate curiosity in your life.
Be curious about things that make you uncomfortable, or maybe just be more comfortable with discomfort.
What I mean by that is, if you look in the field of memory research in general, what you find is, if you want to remember, if you want to learn more, if you want to remember more accurately, if you want to inoculate yourself against misinformation, you have to -- Or if you want to overcome even traumatic events.
Part of the process of learning involves being able to challenge your beliefs, challenge your assumptions, but also giving yourself the time to do these things.
It's like Kahneman talked about thinking fast and slow, and a lot of what you need to remember accurately, a lot of what you need to use memory to make better decisions involves giving yourself the time.
And likewise, these things that we've talked about with error-driven learning, giving yourself the opportunity to make a mistake and actually test yourself on what you think you remember, as opposed to just assuming that you remember it.
So there's so much about when I wrote the book that came back over and over again about becoming comfortable with discomfort.
And then, the third thing I'll just say is, your hypothetical scenario notwithstanding, all we're left with is memories.
And, so, what I mean by this is, what I talk about it based on a term that Danny Kahneman came up with is the "remembering self."
>> Wow.
>> It's not the person who experienced these events, but the person we have when we look back on them.
And I've really taken as part of my life this idea of saying, what are the memories that I want to have one year from now?
>> Wow.
>> And really use that as kind of a signpost for, hey, I've got some time off -- I never really get time off -- but I've got some time where my wife and my daughter have some time off.
What do we want to do?
Well, I know it's going to be a pain to look up Airbnbs, I'm going to kill myself to get the best airfares, blah, blah, blah.
But a memory of taking a week to go to some river and hang out is going to be far more memorable to me than sitting and watching TikTok videos or whatever it would be that I would do.
Right?
And I think it's like, if you look at it from the perspective that, when we look back, we'll remember the highs and the lows and everything else is just noise, you know?
And, so, what are the highs that you want to take with you as opposed to just thinking about everything?
>> That is a beautiful third truth and kind of point that you just said.
What are the memories I want to have a year from now?
I think that's a question, if everyone asks that to themselves right now, they could start to imagine and get intentional about decisions they want to make over the next 3, 6, 12 months.
>> Yeah.
>> Okay, I want to -- A year from now, I want to have this memory.
I want to have this memory of going on this trip with my family, I want to have this memory of taking time off to go work on this hobby or project, or write this book.
I want to have this memory of these shared interactions with friends, family, whatever it might be.
I want to have this memory of doing a random adventure across the country, whatever it might be.
I want to have this memory of being uncomfortable and how much I learned about myself in this process of discomfort.
>> Yeah.
>> You know, for me, I want to have a memory of going through Mexico City and being able to talk to people that don't speak English, and being able to have somewhat of a conversation and be like, wow, I'm so proud of like, what I overcame and how I was able to connect with people with a different language.
All these things.
Charan, this is fascinating.
I've got one final question for you, and that is, what's your definition of greatness?
>> [ Laughs ] Oh, man, that is a really tough one.
Um... I guess, for me, I would say someone who really, like, can inspire and bring, make everyone around them better.
>> Mm-hmm.
>> You know, when I think about all -- I mean, one of the cool things about what I do is I'm not a big believer in genius.
I think there's somebody out there who's better than me at something.
Everyone's better than me at something.
No one's better than me at everything.
Right?
And, so, it's like -- But I'm especially fortunate to be in a field where there's people who I can get in the room with, and I know nothing about what they're talking about, and that they'll tolerate me and help me become better in the process.
And I can think of a thousand people in my life like that who I would say, "This is a great person," because every time I spend with them, I come out feeling both -- I come out more knowledgeable and feeling better about myself in that process.
>> Yes.
That's beautiful.
Dr.
Charan, thank you so much.
We hope you enjoyed this episode and found it valuable.
Stay tuned for more from "The School of Greatness" coming soon on public television.
Again, I'm Lewis Howes.
And if no one has told you lately, I want to remind you that you are loved, you are worthy, and you matter.
And now it's time to go out there and do something great.
If you'd like to continue on the journey of greatness with me, please check out my website lewishowes.com, where you'll find over 1,000 episodes of "The School of Greatness" show, as well as tools and resources to support you in living your best life.
>> The online course Find Your Greatness is available for $19.
Drawn from the lessons Lewis Howes shares in "The School of Greatness," this interactive course will guide you through a step-by-step process to discover your strengths, connect to your passion and purpose, and help create your own blueprint for greatness.
To order, go to lewishowes.com/tv.
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