Rats Regret Things, Too, Like Humans Do, Say Researchers

Regret, that nagging sad feeling we get about, say, a lost opportunity, doesn't just plague humans. Rats also feel regret, according to scientists.

In research published in the latest issue of the journal Nature Neuroscience, researchers said that through measurable tasks, rats exhibited behavior once believed to be "uniquely and fundamentally human," reported ScienceDaily.com.

"Regret is the recognition that you made a mistake, that if you had done something else, you would have been better off," said David Redish, a neuroscience professor at the University of Minnesota who was involved in the study. "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."

Urgent: Do You Approve Or Disapprove of President Obama's Job Performance? Vote Now in Urgent Poll

In the research, Reddish and graduate student Adam Steiner developed a task allowing the rats to eat certain foods at what they called "restaurant row," but the rats only had a certain amount of time at the row. Because the rats preferred to wait longer for certain flavors, researchers could identify their preferences and measure possible mistakes they made.

"In humans, a part of the brain called the orbitofrontal cortex is active during regret," said Reddish. "We found in rats that recognized they had made a mistake, 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."

Redish said researchers were able to build on examples provided by the animal model to better understand why humans do the things that they do.

The results fueled speculation that any mammal could feel regret because they have many of the same brain structures as rats and humans, reported LiveScience.com.

"Regret is something we think of as very human and very cognitive," Reddish said. "We're seeing that the rats are much more cognitive than we thought."

Urgent: Assess Your Heart Attack Risk in Minutes. Click Here.

Related Stories:

• Lyubov Orlova Ghost Cruise Ship Taken Over by Cannibal Rats
  
• Oreos as Addictive as Cocaine? Lab Rats Prove Researchers' Theory