New research has revealed rats show regret, a cognitive behaviour once thought to be uniquely human.
Scientists named the task “Restaurant Row” and presented rats with a series of food options, but gave them limited time at each “restaurant”.
The study revealed rats were willing to wait for certain flavours, implying they had individual preferences. From this information, researchers could measure good deals and bad deals faced by the rats. Sometimes, the rats skipped a good deal and found themselves facing a bad deal.
Professor David Redish, who led the study, said: “The difficult part of this study was separating regret from disappointment, which is when things aren’t as good as you would have hoped. The key to distinguishing between the two was letting the rats choose what to do.
“It’s like waiting in line at a restaurant. If the line is too long at the Chinese food restaurant, then you give up and go to the Indian food restaurant across the street.
“In humans, a part of the brain called the orbitofrontal cortex is active during regret. We found rats recognised they had made a mistake, and indicators in the orbitofrontal cortex represented the missed opportunity.
“Interestingly, the rat’s orbitofrontal cortex represented what the rat should have done, not the missed reward. This makes sense because you don’t regret the thing you didn’t get, you regret the thing you didn’t do.”
Research findings from the study were published in Nature Neuroscience.