podcasts
Collection
Collection for podcasts • 511 items • Updated • 2
text stringlengths 14 7.88k |
|---|
Speaker A: Welcome to the Huberman Lab podcast, where we discuss science and science based tools for everyday life. I'm Andrew Huberman and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine. Today, my guest is Doctor Wendy Suzuki. Doctor Suzuki is a professor of neuroscience and psycholog... |
Speaker B: It's been a while. So great to be here, Andrew, thank you so much for having me. |
Speaker A: Yeah, delighted. I'd like to start off by talking about memory generally, and then I'd love to chat about your incredible work, discovering how exercise and memory interface and what people can do to improve their memory and brain function generally. Yes, but for those that are not familiar, maybe you could ... |
Speaker B: Yeah. Well, I like to say there are four things that make things memorable. Number one is novelty. If it's something new, the very first thing, the very first time we've seen something or experienced something, our brains are drawn to that, our attentional systems draw us to that. And when you are paying att... |
Speaker A: Fantastic. So, novelty, repetition, association and emotional resonance. You could tell us a bit more about the hippocampus, I think, at least for my generation, well, I'm a neuroscientist, but for most people, my generation, I think they first heard about the hippocampus from the movie memento. |
Speaker B: Oh, yeah. |
Speaker A: Where the guy says, hippocampus. And for those of you that haven't seen that movie, it's a bizarrely constructed movie, but an interesting one nonetheless, about memory. But even as a neuroscientist, sometimes I'm perplexed at how the hippocampus works. Maybe you couldn't if you would step us through what th... |
Speaker B: Absolutely. So let's start with the basics. The word hippocampus means seahorse. It is shaped. The structure is shaped like a kind of curlicue seahorse. That is accurate. Everybody, including neuroscience scientists, should know it's a beautiful structure. It is visually, anatomically beautiful with these ki... |
Speaker A: That's fantastic. It sounds like it really sets context, but it can do that with elements from the past, the present, or the future. |
Speaker B: Yes. |
Speaker A: And for neuroscientists, the phrase is domain. We say the time domain, meaning as opposed to just evaluating things in space. It sounds like the time domain of hippocampal functioning is incredibly interesting. |
Speaker B: It is. |
Speaker A: And even the fact that we can have short term, medium term, and long term memories, and we could go down any of these rabbit holes. I'll ask you a true or false, mostly because I just really want to know the answer. A few years ago, the theme in various high profile reviews seemed to be that the hippocampus ... |
Speaker B: That's a tricky statement, because I think that ultimately, yes, that long term memories are stored in the cortex, but those memories are stored in the hippocampus, sometimes for a very, very long time. So how long is too long? Where you say, oh, it's not the hippocampus anymore. If it's four years, does tha... |
Speaker A: Great. As I recall, HM could remember facts from before his surgery. He couldn't form new memories. |
Speaker B: Correct. |
Speaker A: And given that he had no hippocampus, it would at least partially support the idea that some memories are retained outside the hippocampus. |
Speaker B: However, he did have part of his posterior hippocampus intact. So that's the tricky thing, I think initially, in fact, Scoville, the neurosurgeon, overestimated the number of millimeters he intended to remove of the hippocampus. And then when they did this, the very historic MRI of HM later in his life, they... |
Speaker A: I did not know that. There are some memories that can be formed very quickly, so called one trial learning. And I'm just looking at this list again. Novelty, repetition, association and emotional resonance. It seems like some experiences can bypass the need for multiple repetitions. |
Speaker B: Yeah, absolutely. |
Speaker A: And unfortunately, it seems that our nervous system is skewed toward creating one trial memories for negative events, which has a survival adaptive mechanism. What is the neural connection that allows that to happen? Is it the amygdala to hippocampus connection? I mean, as you and I know, that seems like eve... |
Speaker B: Yeah, I mean, I think you've already alluded to it. That is, there is this protective function of our brains that has evolved over the last 2.5 million years that you need to pay attention and remember certain things for your survival. So some things that get stamped in, you know, they're memories, but they'... |
Speaker A: It seems like a location. We talk about conditioned place aversion, which is just geek speak for wanting to avoid the place where something bad happened, or conditioned place preference, wanting to go back to a place where something positive happened, or even looking at a photograph of where you had a wonder... |
Speaker B: Right. |
Speaker A: Or that repetition is hard, or the novelty is simply that it's painful? |
Speaker B: Yes, I've been there. |
Speaker A: Absolutely. Yeah. As have I. Is there something that we can do to leverage knowledge of how the memory system works naturally, to make that a more straightforward process? |
Speaker B: So I immediately turned to the things that I've studied that you talk about so beautifully on your podcast, which are strategies generally to make your brain work better. I was just reminding myself of your podcast about cold, because I use that every morning. |
Speaker A: Oh, you do? Cold. |
Speaker B: I do. |
Speaker A: Just take a moment and tell us, what is your cold exposure protocol? Then I'll take you back to what you're saying. |
Speaker B: So, my cold exposure protocol is at the end of every morning shower that I take. You know, the shower is warm, but I give myself a big blast of cold at the end of that, and it makes me feel so good. And because I've been doing it for several years, it's so much less painful. Okay. I admit it was really painf... |
Speaker A: The brain, basically the cold stimulus, that shock that, you know, catching your breath, et cetera, is adrenaline from the adrenals, but also, from what we understand now, some new neuroimaging. There's epinephrine and norepinephrine released from locus coeruleus, which again, is a brain structure. In the ba... |
Speaker B: Wow. |
Speaker A: So the improved mood and the feeling of alertness is a real thing. |
Speaker B: Yeah, yeah, yeah. So, so I use that. I mean, so basically I use my morning routine. What is my morning routine? I get up, I do a 45 minutes tea meditation. So, meditating over the brewing and drinking of tea, that I learned from a monk who has an institute in Taiwan where he teaches tea meditation. Love it. ... |
Speaker A: I guarantee they are. And I'm impressed that you do all these things, although not surprised, and I should say that the extra hour of sleep is really impressive and extremely beneficial. I'm curious, do you get that in the early part of the night by going to bed earlier? |
Speaker B: Yeah. |
Speaker A: Terrific. And I should just mention, because you're too humble to do it, but I'll say it again that, yes, not only are you a full professor, running a tenured full professor and running a laboratory, you teach undergraduates, you have an important role in public education, multiple books, and you're now dean... |
Speaker B: Absolutely. I definitely notice it if I not able to do it and when I don't. So I do this seven days a week. It's also not just five days, seven days a week. And when I can't do it, it's usually early morning flights or things like that. And I get over it, but it's critical for the working of my brain. |
Speaker A: I love it. And I'll just highlight one thing that you said before we move on, which is that you said sometimes if you get out of the shower before the cold, you'll get back in. That's to me a really beautiful example of condition place preference. You know, there's. So now the cold shower has become somethin... |
Speaker B: Yeah, yeah. So this story happened as I was working to get tenure at NYU. And as you know, it's a stress filled process. They give you six years to, you know, show your stuff, and you are judged in front of all your colleagues, and either they say, okay, you can join the club, or they say, sorry, you are, yo... |
Speaker A: They actually tell people to leave. If you don't get tenure, you're gone. |
Speaker B: You have to leave institution. And so, you know, you work really, really hard. And so my strategy was, I'm just gonna not do anything but work, and I'm just gonna work, and I'm going to just work as hard as I can for the six years. And what happens when you work and you don't have any sort of life outside of... |
Speaker A: I don't know that anyone has had that thought before. |
Speaker B: No, I'm sure people have had that thought. But I thought, maybe I'm just having a good day. But when I thought about it, I thought, it's not just today. My grant writing seems to have been getting smoother. Like, I'm able to focus longer. The sessions feel better to me. And, you know, at that point, the only... |
Speaker A: Fantastic. Quick question about your protocol, just because. And then we'll discuss a few mechanistic things related to what signals the body might be sending the brain, and a little bit more detail on BDNF and some circuitry. So 30 to 45 minutes, it sounds like cardiovascular exercise might have be special.... |
Speaker B: Yeah. |
Speaker A: Than it is to get a mouse to lift weights. Although people have put little ankle weights on mice and done. And the ways of getting mice to do resistance work is actually a little bit barbaric, because oftentimes they'll. They'll incapacitate a limb to overload another limb. So it's an asymmetric thing. It's ... |
Speaker B: Right. |
Speaker A: Or deadlifts or something. Something. |
Speaker B: So. |
Speaker A: But cardiovascular exercise might be special. |
Speaker B: Yeah. |
Speaker A: What are your thoughts on that? And please, first, though, tell us your routine. Your routine is 30 to 45 minutes of. Are you a peloton cycler? Does it matter? |
Speaker B: I think that the data suggests that as long as your heart rate is getting up for these long term effects on your hippocampus and prefrontal cortex, you also get better at shifting and focusing your attention. For that, you need cardiovascular. And what I use is a video workout that I started even before the ... |
Speaker A: And that's a daily thing. Seven days a week. Seven days a week. Fantastic. So, in terms of the way that some of these changes are being conveyed from the body to the brain, that fascinates me. I mean, as you and I know, and I'm sort of a repeating record on the podcast, always saying, you know, you got a bra... |
Speaker B: Yeah. |
Speaker A: Can we enhance the effects of exercise by combining the enhanced blood flow with cognitive work during exercise? Or is it simply a matter of just getting more blood flow up to the hippocampus? |
Speaker B: Yeah, I wish I had the answer to that question, too. My instinct is, yes, it matters, partially because of the work of your colleague, Aaliyah crumb on mindset and the power of that to change how physiologically our body is responding. So how could it not work in her experiments and work in her experiments a... |
Speaker A: Is outside important? I'm a big believer in getting photons into the eyes. |
Speaker B: I think that that study was done indoors on a treadmill, so. And the comparison wasn't done, but moving your, which is great. In the middle of the pandemic, I walked around my apartment for 30 minutes, sometimes just for some variety. Felt like a rat on a running wheel, but, yes. So that minimum amount of mo... |
Speaker A: I love that description of a factor from muscle and a factor from liver, because anytime we're thinking about movement of the body and translating that to the brain, as you so clearly pointed out, that needs to be. It needs to traverse the blood brain barrier. Not everything that happens in the body is commu... |
Speaker B: Well, so after that study, which was quite a while ago, there are more recent studies, still controversial, but showing and demonstrating, using even new and better techniques than were used in that original rusty Gage study, which was groundbreaking at the time, that suggest, and I think show that there are... |
Speaker A: So, yeah, great. And I'll just take a moment to say that I am personally not aware of any studies looking at other forms of exercise besides cardiovascular exercise for sake of brain health. And this, I think, is an important gap in the literature that ought to be filled, whether or not, for instance, high i... |
Speaker B: Absolutely. Let me start with kind of the immediate effects, acute effects, as they're called, of exercise on the brain. So this is asking, what does a one off exercise session do for your brain? And there, there are three major effects that have been reproduced. I've seen it in my lab. Many labs have reprod... |
Speaker A: Making the world a better place. |
Speaker B: Making the world a better place. Energy, the feeling of energy went up. And what we found is in the older population even more than in the younger population, we saw improved performance on both Stroop and Erickson flanker task, which is another task dependent on really focusing in on different letters and p... |
Speaker A: Sorry to interrupt. I just want to make sure I understand. So if, when you say the effects lasted up to 2 hours, does that mean up to 2 hours after you finished exercise or up to 2 hours of memory challenging work? Yeah, just, just to be clear. |
Speaker B: Yeah, that's a great question. So my study looked at the 2 hours after you finish your workout. We gave you these cognitive tests. During that two hour period, you were free to do anything except exercise or eat, and so there was no extra load on people. But 2 hours later, you did do significantly better on ... |
Speaker A: Okay, so if I finish my exercise at 09:00 a.m. even if I start this cognitive work, this mental work at eleven, I'll still see benefits. |
Speaker B: Yes, at least by eleven, because I didn't go farther than 2 hours. So it could last even longer than that. But I have evidence that it lasts for 2 hours. |
Speaker A: And perhaps if I had started the cognitive work and 45 minutes after my exercise ended, it would also be helpful. |
Speaker B: Yes. |
Speaker A: So there's no reason to think that there's a. You have to wait before starting cognitive work? |
Speaker B: No reason at all. |
Speaker A: I'm asking questions of the sort that I get in the comments that we are going to get in the comments section. We always strive for clarity here. So what this tells me is that exercising early in the day may have a special effect. |
Speaker B: Right. |
Speaker A: I, I realize that some people cannot exercise until later in the evening, but you mentioned something earlier that I want to cue people to. It's very, very important. I don't think I've ever mentioned this on a podcast, which is any kind of physical activity will increase cortisol to varying degrees. And so ... |
Speaker B: Yeah, I mean, I like to say that, you know, I know there are moms and dads out there and they just say, look, I have a kid. The kid's more important than my doing my exercise. So you will get benefits if you do it whenever you can. So that's great. More power to you. But what all the neuroscience data sugges... |
Speaker A: Brain, I think about our colleague Eric Kendell, who, not incidentally, has a Nobel Prize and studies memory. Rumor has it that he's been a swimmer for a lot of years that he put in. I think nowadays he's in his nineties now he'll put in half a mile. But he used to swim a mile a day or something of that sort... |
Speaker B: I heard that, too, that he was a swimmer, and he does it very, very religiously. |
Speaker A: Okay. So there are a few other neuroscientists that do that. I can think of a lot of neuroscientists that probably should exercise more. And I don't say that to poke at them. I just would love to see them doing their incredible work for many more decades. And everything that we're talking about today indicat... |
Speaker B: You know, I think there's so much variability, not only because we are individuals, but because our stress levels are different and everybody's anxiety level has gone up in the last couple of years, but that also has an effect. We don't remember as much in a highly stressful, highly anxious situation. So, as... |
Speaker A: Okay, just 30 to 40. It's a day. But I love that per day. I've been doing this whole thing of telling people, oh, the data say 150 to 200 minutes, or zone two cardio, which is kind of moderately hard, but nothing excessively hard. But I love this everyday theme, because whenever I do that, the questions that... |
Speaker B: Yes. |
Speaker A: Sun in your eyes every day, even through cloud cover. Exercise for 30, 45 minutes. Cold shower every day. |
Speaker B: Every day, yeah. |
Speaker A: You know, my understanding of the literature is that somewhere in our fifties or sixties, we start noticing little hiccups in memory for some people younger, for some people later. But I have to imagine that doing the exercise throughout one's entire life is going to help offset some of this. Simply because ... |
Speaker B: Yeah, yeah. I mean, that's what it suggests. One of my favorite studies, and then I want to get back to. You wanted you invited me to share some of my unpublished data on the effects of long term exercise. But first, I want to share one of my favorite studies, which is a longitudinal study done in swedish wo... |
Speaker A: Yeah. Another cause for getting the exercise in consistently. |
Speaker B: Yes. |
Speaker A: Yeah. I am impressed by this ten minute walk and the improvements in mood from just a ten minute walk. But again, I think that daily repetition also, I have to imagine, has effects on the very pathways that allow plasticity. This is something in the realm of neuroplasticity we don't often hear about or think... |
Speaker B: Yeah, yeah. Okay. So when I jumped into the exercise work, everybody was studying people 65 or older, because that's when cognitive decline begins. And if the idea is exercise can help you with your cognition, then makes sense. However, I thought, well, you know, it's great. There's lots of work there. I wan... |
Speaker A: How long are those sessions again? |
Speaker B: 45 minutes. |
Speaker A: 45 minutes. |
Speaker B: 45 minutes. It's a typical spin, spin kind of class. There's a warm up for five minutes and a cool down for five minutes. So it's really 35 minutes. 35 minutes of, you know, they're really pushing you. Yeah. |
Speaker A: So, and so they're breathing reasonably hard. Heart rate? Heart rate is up. |
Speaker B: Heart rate is definitely up. Yeah. Yeah. |
End of preview. Expand in Data Studio
README.md exists but content is empty.
- Downloads last month
- 18