Richmond (USA) (AFP) – The girls who were taken out to the racetrack cannot hide their excitement.
“Black Tail” stands up first, spends a few seconds sniffing its surroundings, then puts its front paws on a lever and zooms out.
After rushing to the finish line, she devours well-earned fruit loops hanging on a “treat tree.”
Black Tail are one of the University of Richmond’s rat drivers, a group that surprised the world in 2019 with their ability to operate small cars.
Rodent is now an ambassador for the school’s Behavioral Neuroscience Laboratory, led by Professor Kelly Lambert.
“People are paying attention to how smart and teachable these animals are,” Lambert explained.
The idea of racing rodents started as a playful challenge from a colleague.
But far from being a novelty, animals are part of a boundary-pushing project exploring how enriching the environment changes the brain, thus potentially solving human mental health challenges. may be hidden.
For Lambert, one of the great failures of modern medicine is the inability of drugs to cure mental illness, despite the enormous profits made by pharmaceutical companies.
These pharmaceutical approaches face increasing scrutiny since a groundbreaking study published in July called into question the theory that chemical imbalances, particularly serotonin deficiencies, cause depression. .
fruits of their labor
Instead, Lambert believes behavioral therapy is the key to treating the psyche.
“Our brain is going from womb to graveyard,” she said. “Given that we live a kind of glamorous life, this is probably important and related to depression.
In her previous experiment, she divided rats into groups of “workers.” Groups were assigned an effort-based reward task to dig a dirt mound for the Froot Loop. handle.
When challenged with stressful tasks, worker bees persisted longer than those conditioned to stay in what psychologists call “learned helplessness.”
And when tasked with swimming, worker bees displayed greater emotional resilience, as evidenced by higher ratios of the hormones dehydroepiandrosterone and cortisol in their feces.
Rats that learned to drive also had biomarkers of greater resilience and less stress. It is possible that
Lab expert Olivia Harding said, “They make paths over and over again in the wild. I wanted to check what was going on,” he explained.
Training was not simple. The team first tried fine-tuning the driving maneuver with the rat’s snout, but found that the rat preferred to stand on its hind legs and use its front legs.
Early car models required rats to touch wires placed in the front, left, or right of the car, completing a gentle electrical circuit that corresponded to the direction of travel.
Now, however, they travel in more elaborate vehicles using levers designed by roboticists.
Even when the car was placed in an unfamiliar location and away from the treat, the rats learned to turn the car and move towards the reward. This indicates that advanced cognitive processing is at work.
Today’s driving ladies, Black-Tail and Multi-Color-Tail, show distinct signs of “anticipatory” behavior when a human walks into a room, walks back and forth, and attempts to climb walls.
But just like humans, not all rats have the same interests. One individual seemed eager to drive just for fun, while others seemed to drive just for a snack.
into the wild
Female rats in particular have long been neglected by science. That’s because early generations of researchers thought the rat’s four-day estrus cycle confounded the findings.
This trend can deprive scientists of women-specific insights, and Lambert is determined to reverse this trend in her experiments, now also a prerequisite for federal funding.
Early in his career, Lambert realized that studying rats living “poor” lives in obstacle courses and inactive cages was no more useful than studying humans in solitary confinement. I was aware of that.
In her driving study, rats housed in nutrient-rich cages performed much better at driving tasks.
Her latest paper focuses on the differences between laboratory rats and wild-caught rats, the latter of which have larger brains, more brain cells and a disease-fighting spleen than their captive cousins. I found that it was bigger and my stress levels were much higher.
“It’s kind of shocking,” she said, that there’s been so little interest in understanding these differences despite their potential implications for human medicine.
It also raises an interesting philosophical question: Are we more like lab rats in cages, lab rats in rich settings, or wild rats?
“I feel a little more like a prepared lab rat than a wild rat,” thinks Lambert.
But wild rats, who, like our ancestors, must forage and avoid predators in their daily lives may teach us something about mental resilience. not.
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