The scientists constructed a little car the rats could enter and control by touching some metal wires to either turn or drive forwards. They found that not only could rats be trained to drive in fairly complex patterns, but learning to drive lowered their stress levels. The treatment group actually seemed to enjoy the task as they continued to drive even after they no longer received rewards for completing the task. The control group was harder to train and didn’t drive as well as the treatment group.
What they actually studied was the effects of “enriched environments” on lab animals. An enriched environment is a housing environment (in the lab), that mimics the animals natural habitat more closely than a standard lab cage. The treatment animals lived together in a multi-level cage with different objects/toys that were changed weekly to provide variety. In this case the enriched environment was similar to how a pet rat might live in someones home, as opposed to how lab animals usually are shown to be living in movies and TV shows.
Rats are often used as models to study how the brain works, both in medicine and in psychology. Knowing how the environment affects rats can help us understand how similar environments affects humans, as well as how to design better rat-based studies. Since rats can learn tasks as complex as operating a motor vehicle and navigating to where they want to go, scientist can use them as models for human behavior in even more complex situations in the future.
Newscientist has written a news article about the study with some really cute videos of the rats driving around: https://www.newscientist.com/article/2220721-scientists-have-trained-rats-to-drive-tiny-cars-to-collect-food/
The full study is:
Crawford, L.E. & Knouse, L.E. & Kent, Molly & Vavra, D. & Harding, Olivia & LeServe, D. & Fox, N. & Hu, X. & Li, P. & Glory, C. & Lambert, K. (2019). Enriched Environment Exposure Accelerates Rodent Driving Skills. Behavioural Brain Research. 378. 112309. 10.1016/j.bbr.2019.112309.
It is available to read here if you want to read it.