Regret In Humans and Non-Humans

 

    Regret is a feeling or emotion that all humans face throughout their lives. The experience of regret is usually tied with negative emotions such as depression or sadness and maybe sometimes anger as well. Regret is an experience that varies from person to person, and it stems from the realization that one has made a mistake or that they have chosen an option that may not be the best, or that they have performed or done something that they should not have. For the longest time it was believed that regret may have been an experience reserved to just humans, but further research with non-human creatures has shown that other animals are also capable of experiencing regret and that regret can vary due to different factors such as age. Experiencing regret may not be the best feeling but it is possibly crucial for survival.

      Many research labs today are studying the feeling of regret in non-human animals. A popular animal of choice are mice. In Brian M. Sweis’s research lab, 31 mice were trained in the Restaurant Row economic decision- making task for 70 consecutive days. In this experiment mice were placed in a contraption with four different sides, each side which dispenses a different flavored food pellet. Each of the four sides with their respective flavors had an auditory signal which notified the mice of how long it would take before the food would dispense. The mice had one hour to earn food for the whole day, it was up to them on how they would invest their time to get the most food for the whole day. What Sweis and his fellow researchers found is that these mice showed evidence of regret-like behaviors. These mice showed hesitation or change in decisions that corrected prior disadvantageous choices. For example, a mouse may have invested a lot of time waiting for a certain flavor and on that day, it did not get sufficient food. Well, the next day the mouse went to an area or chose a flavor that did not have such a high time investment to increase food consumption for that day. In Sweis’s paper, “Mice Learn to Avoid Regret”, he mentions how after the mice had a change-of-mind event the subsequent decisions made by the mice seemed to have made up the loss of decision speed, pellet consumption speed and also the willingness to wait for the pellets. Much like humans, mice show similar behaviors following a regretful decision. They show a change in behavior that tries to minimize past errors or disadvantages.

            In an article by Ferris Jabr, titled, “The Rue Age: Older Adults Disengage from Regrets, Young People Fixate on Them”, Jabr talks about the feeling of regret in human beings and how there may be a difference in how younger individuals process regret versus older individuals. In this article, Jabr explains an experiment performed by a group of researchers led by Stefanie Brassen of the University Medical Center Hamburg-Eppendorf in Germany. In this experiment 20 healthy young participants in their 20s, 20 healthy adult individuals around 65 years of age and 20 depressed adult individuals around 65 years of age were told to play a gambling game in an MRI machine. Participants were presented with 8 unopened crates on a computer screen, 7 of which had gold in them and 1 of which had a demon cartoon. Participants were told to open each crate from left to right and after opening it they had the choice of leaving the game with what they have or continuing. If the participants uncovered the demon, whatever they had would be stolen and they would be forced to quit the game with nothing. If the participants quit while they were ahead, the position of the demon would be revealed, and the participants would know if they made the right choice or if they quit too soon. While playing the game, the researchers analyzed the ventral striatum, which responds to rewards. If a participant received a reward their ventral striatum would show increased activity, if they lost, then the ventral striatum would show decreased activity. What the researcher discovered from the brain-imaging results was that the ventral striatum showed very low activation when the young individuals and the depressed adults experienced loss or in other words regret. Whereas, the ventral striatum of the healthy adults had little to no change in activity when experiencing loss or regret. The results from Brassen’s research suggest that the brains of younger individuals and the depressed are more susceptible to regret than that of the brains of elderly adults.

            The research done by Sweis et al (2018) and the research experiment done by Stefani Brassen, as described in Ferris Jabr’s article, show that ,just as young human individuals, young mice also experience regret and respond to the regretful decisions in a similar manner. The mice in Sweis’s study were young 13-week-old males and when they were observed in the decision-making task, they show clear signs of regret by changing their decisions and choices based on past experiences. This data shows that the experience of regret may be something that is present in not just humans, but other animals such as mice and that it is something that is crucial for survival as well. Like humans, mice cannot be taught the feeling of regret and how to react to regret, it is something that is natural and something that plays a huge role on how one needs to change based on the environment and based on decisions made in that environment. This research regarding regret in other animals may also be crucial in further understanding how learning and long-term memory are similar or different from humans and how the experience of regret may impact long-term memory retention.

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Citation

Jabr, Ferris. “The Rue Age: Older Adults Disengage from Regrets, Young People Fixate on Them.” Scientific American, Scientific American, 19 Apr. 2012, www.scientificamerican.com/article/old-people-manage-regret/?print=true.

Sweis, Brian M., et al. “Mice Learn to Avoid Regret.” PLOS Biology, Public Library of Science, 21 June 2018, journals.plos.org/plosbiology/article?id=10.1371%2Fjournal.pbio.2005853.