The scientists who taught rats to drive itty bitty cars are back at it again -- and this time, they have even more insights about how much these rodents enjoy their unusual pastime.

In an essay for The Conversation, University of Richmond neuroscientist Kelly Lambert said that over the course of her experiments teaching rats how to drive, she and her colleagues learned a lot about rewards and anticipation.

Lambert and her team have for years now been teaching lab rats how to drive as a way of studying the relationship between animal environments, stress, and the development of cognition and new skills. The adorable experiments went so viral, they ended up in a 2022 Netflix documentary -- but according to Lambert, that's not the whole story.

During the bleak and lonely period marked by COVID-19 lockdowns in 2020, the neuroscientist said that even her driving lab rats seemed to be experiencing emotional isolation. That summer, she recalled, she walked into her lab and "noticed something unusual."

"The three driving-trained rats eagerly ran to the side of the cage," Lambert explained, "jumping up like my dog does when asked if he wants to take a walk."

"Had the rats always done this and I just hadn't noticed? Were they just eager for a Froot Loop, or anticipating the drive itself?" she queried. "Whatever the case, they appeared to be feeling something positive -- perhaps excitement and anticipation."

While rats would never encounter such "rodent-operated vehicles" in the wild, the ones in Lambert's lab didn't just take to the training itself -- they actually seemed to be really into it.

"Unexpectedly, we found that the rats had an intense motivation for their driving training, often jumping into the car and revving the 'lever engine' before their vehicle hit the road," she wrote. "Why was that?"

Beyond simply enjoying their fruity cereal rewards, Lambert and her team hypothesized that anticipation could be as positive an experience as the prize itself.

The rats trained to wait for positive experiences seemed to have better cognition than their instantly-gratified counterparts in the control group, and when offered the choice between a shorter path to a Fruit Loop via walking or a longer path involving driving the vehicles, two of three of the lab rodents chose to drive -- suggesting, Lambert wrote, that they "enjoy both the journey and the rewarding destination."

There's a lesson in these experiments for humans, the neuroscientist concluded: that waiting for positive and pleasurable experiences may end up being as gratifying as the experience itself.

"Rather than pushing buttons for instant rewards," she described, "they remind us that planning, anticipating and enjoying the ride may be key to a healthy brain. "