RICHMOND (AFP) - After astonishing the world in 2019 with their ability to drive miniature cars, the American University of Richmond rats are part of a pioneering project exploring the role of environmental enrichment in shaping the brain, which could help in the long term to solve mental health problems in young people. Humans.

On a racetrack, Black Tail Rat spends a few seconds sniffing the place, before putting his legs on a winch and driving off at full speed -- and when he reaches his destination, he devours a well-deserved treat.

Kelly Lambert, director of the Behavioral Neuroscience Laboratory at the University of Richmond, said the experiment "draws people's attention to the intelligence and learning capacity of these animals."

Lambert considers that one of the greatest failures of modern medicine is its inability to treat mental illness with the help of drugs, despite the fact that pharmaceutical companies are making profits in this field.

These pharmacological approaches have come increasingly into question, after the publication of a major study in July that called into question the theory that chemical imbalances, particularly a lack of serotonin, would cause depression.

Instead, Kelly Lambert sees behavioral therapy as key to treating the mind, hence the small mammal study.

"Our brains change from womb to grave," she says, explaining that having an active life, one way or another, can affect the likelihood of depression.

In an earlier experiment, rats were divided into a first group of rodents that had to make an effort to get a reward - in this case digging in a mound of soil - and a control group in which rats had to get rewards for nothing.

Faced with stressful tasks, the first group of rats survived longer than those conditioned to survive in a state the scientists call "learned helplessness."

When forced to swim, the first group rats had a hormonal reaction that indicated greater emotional resilience.
Rats that learned to drive also showed greater emotional cohesion and lower levels of stress, which may be related to satisfaction with learning new skills, according to Kelly Lambert.

Researcher Olivia Harding says that these animals "make paths in nature that they take all the time, and we wanted to see if they were able to maintain this excellent sense of direction inside a vehicle."

Learning wasn't easy: the mice first had to actuate the controls by clicking their snouts, before the scientists discovered that they preferred standing on their hind legs and using their front legs to drive.

Even when the vehicle was in an unfamiliar situation, the rodents were able to steer it the right way and get the treats, evidence of their advanced cognitive ability.

In this experiment, the so-called "black-tailed" and "multi-colored-tailed" rats showed an ability to "anticipate" by fidgeting when humans arrived and sprinting in an attempt to climb cage walls.

Just like humans, not all rats have the same interests: while some seem to enjoy driving themselves, others do so just for the rewards, and a third group don't even care.

Scientists have long ignored female mice, believing that their four-day menstrual cycle could change the results of research, thus depriving themselves of in-depth knowledge about them.

This phenomenon Kelly Lambert has worked to combat in her own experiences, while the federal conditions for receiving funds to conduct research in the United States, encourage to follow her example.

The director of the Behavioral Neuroscience Laboratory realized early in her career that studying mice living in cages with environmental "unenrichment"—without obstacle races or activities—didn't hold as much interest as studying confined humans.
For example, rats raised in cages without environmental enrichment were more successful at driving a car than others.
Her latest research concluded that wild mice have larger brains than laboratory rats, more neurons, a larger spleen for better disease fighting, and much higher stress levels.
Which leads us to a philosophical question: Are we more like lab rats, caged animals with environmental enrichment, or wild animals?
"I feel a little more like a lab rat than a wild rat," Kelly Lambert laughs.
Wild rats that have to scavenge for food in the garbage every day and avoid predators may have behavior similar to that of our ancestors, and humans can draw lessons from them in terms of mental resistance.