“Looking at a tiny part of the brain in a mouse, we can understand how the brain learns, and we can makes predictions about how the human brain might work,” said Kishore Kuchibhotla, a Johns Hopkins neuroscientist who studies learning in humans and animals.

“The field of neuroscience has made great progress decoding motor activity and how the brain processes sight and sound. But a holy grail of this type of research is thought—what comes between the hearing and the doing—we’re all still trying to understand the patterns of brain activity that underly higher-order cognitive processes. These findings are a step in that direction.”

Although the ability to learn quickly would benefit any animal in the wild, animals studied in labs seem to learn slowly and methodically. It typically takes mice, for instance, thousands of tries to learn a task, several hundred at best.

Kuchibhotla’s lab previously found that animals’ performance doesn’t necessarily sync with their knowledge—or that animals might know a lot more than they demonstrate in tests. The lab also found that animals that seem to be slow learners might be testing their new knowledge. But by merely watching animals struggle at tasks, they couldn’t tell a slow learner from a strategic tester of boundaries.

“We are interested in the idea that humans and other animals may know things about the world, things that they choose not to show,” Kuchibhotla said. “Our core question is what is the neural basis of this distinction between learning and performance.”

The researchers taught mice to lick when they heard one tone but not to lick when they heard a different sound. From the moment training began, the team recorded the activity of neurons in the auditory cortex, an area of the brain associated with hearing and perception.

There were two major surprises. First, the mice learned in 20 to 40 tries, “extraordinarily fast,” according to Kuchibhotla. And second, this learning activity happened in the sensory cortex, something that has typically been associated with nonsensory brain areas.