Scientist Explains Why Her Lab Taught Rats to Drive Tiny Cars

So many of us are caught up in the rat race,

that endless loop of driving to work,

toiling away, driving back, all for just a few crumbs.

But behold the literal rat race,

in which researchers trained rodents to drive tiny cars.

Surprisingly, unlike for most of us humans,

the driving actually seems to lower the rats' stress levels,

but maybe that's partly because at the end,

if they were good drivers, they got Froot Loops.

To find out more, we talked with

researcher Kelly Lambert about

her rodent-operated vehicles, those would be ROVs,

and what implications this might have for humans.

So, what is this research

that you're carrying out here with rodents?

We wanted to teach rats to drive cars!

It's a complex task, and so we used some old-fashioned

psychological behavioral training techniques

and Froot Loops to shape rats to get into cars

and to use the car as a tool

to navigate an environment to get to that ultimate reward,

which is the Froot Loop.

And so we looked in our most recent study

to see if the complexity of their environments,

if they had an enriched environment or not,

influenced how quickly they could learn.

And it did.

Walk us through the experimental setup here.

We had two groups.

One group was housed in an enriched environment,

kind of a Disneyland of sorts for rats.

So, they had different stimuli to interact with,

and the other group was in just standard laboratory cages.

So, they had everything they needed but no Disneyland.

And so we were interested in,

if the enriched environment would facilitate

their learning to drive.

We'd already shown that we could teach the rats to drive,

and we also taught them to steer.

So, we had forward driving bars,

and then bars on the left and right

so they could steer in different directions.

But they were able to do some pretty complex turns.

What made a, quote unquote, good rat driver?

To drive four times, four clean drives,

jumping in the car, getting to the Froot Loop reward,

and then coming back and doing that again.

So, only our enriched environment animals

were able to do that.

None of our standard housed animals.

They could get bits and pieces of it,

but they were not able to put it together

more than one time.

So, in that particular study,

our standard housed animals

did not get a driver's license. [laughing]

They have to wait in line again at the DMV

to take their test. Yeah, yeah.

Not fun, even for a Froot Loop.

What kinds of vehicles do you give to a rodent in the lab?

We could not find one on Amazon [laughing]

so we had to build our own.

So, we started with a basic plastic container

and we cut a window out and put the bars,

the steering bars at the end

so that they could just grab the bars,

that they would complete the circuit,

the electrical circuit.

Although the rats couldn't feel anything.

And we added wheels.

So that's our rodent operated vehicle design.

Very simple.

You actually could tell that

they might actually be somewhat enjoying this process?

Can you talk about how you were able to measure that?

So, what we did with this last published study.

Once we taught them to drive,

then we took the reward away.

It's called extinction trials.

And we did that for four days.

And even the fourth day

after they've been driving and getting nothing,

they would still jump right into the car very quickly.

That suggested that they had

a positive association with that.

So, that's one way we've gotten at this question of,

is this a pleasurable experience, or a positive experience?

The stress part.

So, our very glamorous lab that I have,

we like to measure stress hormones in rat poop.

We can extract the hormones

and we look at a stress hormone

that is similar to cortisol in humans,

but it's corticosterone in rats.

And then another hormone is DHEA,

is the abbreviation.

Our research suggests that DHEA kind of

buffers against the toxicity

of chronically high stress hormone levels

and throughout the training

for all of the animals in this published group,

regardless of whether or not

they were in the standard group or the enriched group,

the DHEA to quart ratio went up in a healthy way.

So, that suggests that it's healthy.

And then in a previous study that hasn't been published,

we had a different design where we had

half the animals were drivers, like we'd done before.

And then half the animals,

we drove them around the same distance

with the same car, but did it via remote control.

We called those the Uber rats,

they were just passenger rats versus the driver rats.

And in that study, only the driver rats

had the increased DHEA.

So, what comes next with these rats in your lab?

Are you gonna make rat race-cars?

[Kelly laughing] SUVs for their friends?

We thought about a little competition.

So, we're thinking about neuroplasticity,

and getting to the brain measures of neuroplasticity.

Neuroplasticity refers to the brain's ability to change

to alter environments or lifestyle.

So in my lab, we're looking at physical measures.

I like to look our rats at the end of their lives,

they're still alive and driving,

and then maybe compare their brains to

brains of rats that did not receive the training

to see if they have some of those measures

of neuroplasticity.

And we just have to be careful

when we maybe extrapolate what we're finding here

with rodents up to humans,

but I was wondering if you could talk about

what this might suggest about how our own brains might work

when it comes to stimulation and learning.

We needed engagement with our physical worlds

and our social worlds,

and our brains need experience to develop.

So, I think it can be generalized

or translated to the human brain.

Another kind of something I thought about is,

I wonder, since a lot of biomedical research

is conducted on rats in those standard boring cages,

if that is influencing the validity

of the results that we're finding?

And I think we need to be looking at

more authentic behaviors and complex behaviors.

And if we want to learn about

our complex emotional disorders, our cognitive changes,

we probably need to look at more complex research designs.

So, I think we need to step up our game as scientists,

and look at something besides a rat and a mouse,

and also look at behaviors beyond pressing a bar

or turning right or left in a simple maze,

because even the rat brain can do so much more than that.

So, you saw that there was actually

some enjoyment that these rats were getting

out of learning this new task.

Might that be kind of the same for humans?

Learning a new language or learning to do cabinetry?

Whatever floats your boat.

Absolutely.

I think that we have individual differences

in what we like, but engaging in different tasks,

I think more interactives,

can be really good for the brain.

So, learning is an enjoyable experience,

and I think it gives us a sense

that we're gaining control over our environment.

A sense of mastery.

And this makes us feel better about

our competency in this world.

So, even though it's kind of a simplistic idea,

teaching a rat to drive a car,

it seems to be taking us into some complex,

even philosophical [laughing] kind of arenas

as we think about what brains can do.

Thank you for taking the time to chat with us.

It's been my pleasure.

Thank you for your interest in our driving rats.

[light, curious music]