Rats Regret Their Bad Decisions, Just Like We Do

Animals: They're just like us, right? Well, at least rodents are. Turns out rats regret their bad life decisions just like we do. A new study out of the University of Minnesota found that sad rats who made crappy decisions expressed remorse for their actions later on, according to a study published in Nature Neuroscience. It's just another way science is making you feel more normal, but probably not any less, well, regretful.

The study, completed by David Redish and a grad student, Adam Steiner, also found that rats alter their behavior to make up for past mistakes — just like we (should) do. The scientists defined regret as something more than just run-of-the-mill aw-shucks syndrome, according to the study's abstract.

Disappointment entails the recognition that one did not get the value expected. In contrast, regret entails recognition that an alternative (counterfactual) action would have produced a more valued outcome.

The scientists used an experiment called "Restaurant Row" to test the rats' capacity for regret. Wired describes the experiment in detail. Short version: The rat learned that four different places offered four different types of food, and when it ran past those places a sound indicated how long it would take to get the food. The catch is that the rats didn't know how long the wait would be at the next place; it might be longer.

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The results depended on which flavors the rats liked best, but basically, if a rat skipped out on a long wait and ended up going on and waiting for longer, they ended up looking back longingly at the last "restaurant" where they had a better deal going. As Redish described it to Wired:

It looked like Homer Simpson going, ‘D’oh!’

After missing out, the rats usually took the bad deal and ate it quickly before running on, probably feeling like they'd wasted their time. To add credence to the argument, scientists also measured cells in the rats' brain where humans are known to express regret, and those fired, too. In science-speak, when rats moved on only to get screwed at the next "restaurant," meaning they made a bad decision, here's what happened:

In these situations, rats looked backwards toward the lost option, cells within orbitofrontal cortex and ventral striatum represented the missed action, rats were more likely to wait for the long delay, and rats rushed through eating the food after that delay.