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Rats have mastered the art of driving a tiny car, suggesting that their brains are more flexible than we thought. The finding could be used to understand how learning new skills relieves stress and how neurological and psychiatric conditions affect mental capabilities.

We know that rodents can learn to recognise objects, press bars and find their way around mazes. These tests are often used to study how brain conditions affect cognitive function, but they only capture a narrow window of animal cognition, says Kelly Lambert at the University of Richmond in Virginia.

Lambert and her colleagues wondered if rats could learn the more sophisticated task of operating a moving vehicle.

They constructed a tiny car out of a clear plastic food container on wheels, with an aluminium floor and three copper bars functioning as a steering wheel. When a rat stood on the aluminium floor and gripped the copper bars with their paws, they completed an electrical circuit that propelled the car forward. Touching the left, centre or right bar steered the car in different directions.

Six female and 11 male rats were trained to drive the car in rectangular arenas up to 4 square metres in size. They were rewarded with Froot Loop cereal pieces when they touched the steering bars and drove the car forward.

The team encouraged the rats to advance their driving skills by placing the food rewards at increasingly distant points around the arena. “They learned to navigate the car in unique ways and engaged in steering patterns they had never used to eventually arrive at the reward,” says Lambert.