Short Wave - These Rats Can Drive. What's Happening In Their Brains?

Episode Date: December 3, 2024

In neuroscientist Kelly Lambert's lab at the University of Richmond, rats hop into cars, rev their engines and skid across the floor of an arena. Researchers taught these tiny rodents to drive — and turns out, they really like it. But why?Host Regina G. Barber talks with Kelly about her driving rats, and what they tell us about anticipation, neuroplasticity, and decision making. Plus, why optimism might be good for rats, and for humans too.Want to hear more fun animal stories? Let us know at [e-mail] — we read every email.Listen to every episode of Short Wave sponsor-free and support our work at NPR by signing up for Short Wave+ at plus.npr.org/shortwave.See pcm.adswizz.com for information about our collection and use of personal data for sponsorship and to manage your podcast sponsorship preferences.NPR Privacy Policy

You're listening to Shortwave from NPR. Hey, Shortwaveers, Regina Barber here. And today, our story starts with a rat scientist. You know, I know we're not a big rat and they're not little humans. But at a basic level, they have mostly all the same brain areas, neurochemicals like dopamine and serotonin and plasticity kind of fertilizers that we look at. All of that is in a rat brain. That's Kelly Lambert. She's a professor of behavioral neuroscience at the University of Richmond. And a while ago, this colleague of hers, a cognitive scientist who's into robotics and design, reached out with kind of a weird question.

She sent an email one night, so Kelly, can you teach a rat to drive a car? And I'd consider myself a serious-minded neuroscientist. So my initial response was, why would I want to do that? But then, she reconsidered. Once you start thinking about teaching a rat to drive a car, you can't not think about it. You can't stop thinking about it. Fast forward to a couple years later, guess what this is? If you guess that's the sound of a rat driving a tiny car, you're right. Kelly's rats are in a lab at the University of Richmond zooming in these four-wheeled little plastic boxes around this big arena. Almost like a playpin around the entire room and then,

some kind of flooring that we put, that we roll out that's a flat surface, and it's black and white check, so it kind of has this raceway kind of idea. And we start the car on one end, and at the other end is what we call the fruit loop tree. And we have little straws with fruit loops and they attached via marshmallows. We do give them healthy food. They just have these treats. And in 2020, right at the peak of the COVID lockdown, watching these rats, Kelly had a breakthrough. We were all feeling isolated, low emotion. The students had been sent home. So I remember going in one day, feeling that low kind of feeling.

And we had three rats that were our driver rats. And they ran up to the side of the cage, literally kind of jumping up and down like my dog, Brody does. When I say, you want to go for a walk? And he's flipping around. And they were reaching out to me. Now, maybe they just associated me with a big fruit loop. But it made me feel accepted good that they were excited for something. So that's what Kelly and our team are studying now, anticipation.

They teach their rats how to drive these little cars in different situations and environments. And they study how these rats respond, how it changes their brains and their behavior. So today on the show, we're learning from rats about anticipation, decision-making, and how to enjoy life. I'm Regina Barber, and you're listening to. listening to Shortwave, the science podcast from NPR. Hey, short waver is Regina Barber here. Before we get back to the show, can you give me a quick minute to talk to you about what makes shortwave possible? Aside from caffeine, a well-calibrated circadian rhythm, and a love of science, specifically astronomy.

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NPR Plus today. Join us at plus.mpr.org. That link is in our episode notes. And if you don't want podcast benefits, no one can stop you from simply just going to donate.npr.org. Your gifts are tax deductible, either way you choose to give. Okay. Thank you for listening and back to the show. Okay, Kelly, describe this setup. So, like, what do the carts look like that the rats are driving? And how do they do it? Right now, we're in our third version of our rat car. So we're in Rat Car 3 that we call Rodent Operated Vehicles.

They're a little smaller than a shoe box. And they have the tires and they have a steering mechanism that we had to figure out. And we use kind of old-fashioned, operant behavioral conditioning with a fruit. Loop as the incentive. That's the currency of my lab, to shape them behaviorally, to enter the car, to stay in the car, to press the lever, and keep that lever pressed to activate and to drive the car to the Fruit Loop Tree, which is their destination. Okay, that seems like a lot of work, but you're saying these rats, they like this. They like driving. Like, how do you know that? Is it from their brains? Is it from their behavior? Or is it like both?

That's a really interesting question and probably the most popular question, frequent question that people have asked me, do they like it? I can't give them a Qualtrick survey or something like that. So I can look at their behavior. When we bring them into the lab and to their driving arena, we transport them from their transport cage into the car. They jump in automatically. So that suggests that they're at least approaching something and that's usually related to something they like. and as we're putting them into the driving arena before they even hit the rat road, they start activating the lever and it sounds like they're revving up the engine. Yeah, I watched the videos. I saw them like revving it up and really seemed like they were like so ready to go.

Yeah. So approach is one way that a behavioral scientist like myself could understand that. I wanted to explore it a little bit more definitively with that small group. So they had only been able to access the fruit loop tree in their car in the past training. But I asked my students to let them get into the arena without the car and just see that they could clearly just walk down to that fruit loop tree. So the test in this preliminary study was to put the car at one end of the arena, as we always had done. The fruit loop tree was in the other end and we put the rat outside of the car just in the middle of the arena. So the most efficient way to get to the fruit loop would be to simply walk or run to the fruit loop tree, eat all the fruit loops you want. One rat consistently did this. We have individual differences with rats, and I love that. That's the smart one.

Yeah. To the rats, they hesitated, they turned around, saw the car, and not walk, but kind of ran to the car, jumped in and drove to the fruit loop tree. Not once, not twice, but day after day, they are preferring to drive to the fruit loop tree. root loop tree as opposed to walk to it. That driving increased the anticipation. Okay, I'm just going to pause you right there because I want to talk about this like anticipation because I know that there are these other studies out there indicating that there's like natural dopamine being released in these rats as they're like anticipating reward. It seems like you're like building on these studies.

Can you explain how like driving fits into all that? Yeah. I developed a whole and I'm with my colleagues a whole new protocol looking at a call unpredictable positive experience responses. So at random times during the day, we're giving them these positive experiences, so they never know when it's coming. And then they have to wait for it. So I'm really trying to ramp up anticipation for something good. And we are starting to write up our initial data, but it's looking like we are indeed sculpting their brains differently, their behaviors, their vocalizations, whether or not they're happy or sad calls. And so if we think, if I

think about my life, if we're looking forward to a vacation with a family and you're thinking and planning, it's rare that the actual event meets all those expectations. So maybe the anticipation is even more rewarding than the actual event sometimes. But if we deprive ourselves of all that anticipation, we're really depriving our brains of a lot of feel-good chemicals and such. So the rats may be prolonging the feel-good time, the time that they're enjoying. driving or anticipating that fruit loop. Okay, so you mentioned that they're like physical, like, behavior cues that these rats are, they are experiencing this dopamine. Can you tell me a little bit more than that?

Yeah, again, it's exploratory, but just kind of blew my mind. So we were doing another test with these, we call them upper trained or positive anticipation trained rats, where they were in an arena. And a student said, Dr. Lambert, why does the rat have its tail sticking straight up? And it was like an umbrella, you know, kind of a hook. And sure enough, the upper trained or anticipatory trained animals had it sticking up more. And I didn't know what this meant. So I put a picture on social media. So does anyone seen this?

Because I just hadn't. And a few people said, oh, yes, if you inject morphine into a mouse or a rodent, their tail goes up. And I thought, have we changed these opiates and these animals through behavioral training? So dopamine for pleasure and opiates for well-being, that's a pretty good cocktail from behavioral training. And I've introduced this word behavior suiticals that we can change. So it was maybe the perfect behavior suitable, but we're still exploring. It's just great to watch the animals and they give you clues about what to look at next.

That's amazing. And I really like this term that you've coined this like behavior suiticals, this idea that behaviors can alter your brain. chemistry, which you're seeing, like similar to pharmaceuticals. How does this work with driving rats, like, add to that line of research? Yeah, so we found that just going through the training itself, regardless if they learn to drive or not, that changed at least the hormone profiles. So it doesn't even matter if they're a good driver or not.

They just like driving. It's the process. Journey, not the destination. Yeah. Really. There's research to suggest that stress can impair. neuroplasticity or at least the healthier kind of versions of plasticity. So if this training is helping them regulate their emotions and have lower levels of stress hormones, that's going to have

probably a positive impact on the brain. So if we know more about how we can intentionally and systematically change our behavior to change our brains in healthy ways, most of the research is related to changing neurochemistry through pharmacy. But I wanted there to be more attention on the behavior. We know that cognitive behavioral therapy is very effective with humans, but we don't have good preclinical models. We're not sure exactly what that's doing. So I'm trying to replicate some of that with the animals so that we know more about what

it's doing, and that may elevate respect for behavioral interventions. Yeah. And neuroplasticity, as you're saying, is like the brain's ability to change and learn, right? And so to sum up, like, training new skills helps these rats, like regulate emotions, which lower stress, which makes their neuroplasticity stronger, right? Like it's a cycle. You got it, yeah. And this has lots of lessons.

But now I'm excited about what we can learn from other animals. Rats don't represent all mammals or all animals or all brains. More research has done on mice now. It's convenient. We know a lot about how to house them and do research. But let's look at wild animals. Let's look at different. I love raccoons.

They're out there working the environment and they're so smart. They're so smart. Keep them in the lab. But they look like primate brains. There's a reason we can't invent or design a garbage can to keep them out. So I think there are a lot of species out there that hold a lot of secrets that may unlock some mysteries about some of the illness, psychiatric and neurological illnesses that we face. So we need to diversify our research portfolios. Wow.

Aside from like what is scientifically proven and like how similar rats brains are to human brains, what has this work done for you like personally? Has it changed how you look at life, how you look at anticipation and about delayed gratification and working for things? Yes. And on so many levels, a lot of research is focused on protecting children from trauma. And that's so important. We have adverse childhood experiences. We want to minimize the stress, the trauma. Little challenges are great, but horrible things that happen.

That's so impactful for the brain, and we need to keep that up. But what about if a child has something to look forward to? While a pediatrician is asking about stressors in a child's life, I'd love to start thinking about the impact of asking, what are you looking forward to? Anticipation kicks in a lot of really healthy brain responses related to curiosity and planning and all that dopaminergic activity. So we need to balance the scale and we've been a little one-sided focusing on avoiding the negative. But we need to add to that to extend that anticipation like we're doing with the rats where maybe they never know when something good is going to happen or they know that they can wait and it's coming.

And that's also, I think, very healthy for brains. We're exploring it. I love it. I'm going to take this and be like, you know, you can actually think that random good things are going to happen, too, not just bad things. That's not the way our culture is. It's just what is the next bad thing that's going to happen. Right. But now I'm going to be like your rats.

I'm going to be like one day there'll be a fruit loop tree. Yes. Yes. Well, thank you so much for sharing your work with us. You're welcome. I love sharing our brain stories with anyone interested. interested in hearing them. This episode was produced by Hannah Chin.

It was edited by a showrunner Rebecca Ramirez. Tyler Jones checked the facts. James Keely was the audio engineer. Beth Donovan is our senior director and Colleen Campbell is our senior vice president of podcasting strategy. I'm Regina Barber. Thank you for listening to Shortwave from NPR.