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It would make sense that working hard for a reward, however big or small, would increase your enjoyment of said reward: A beer tastes better at the end of a long day of work, that kind of thing. This has been the theory held by researchers who study the relationship between stress and reward, at any rate, but a new paper in the Journal of Experimental Psychology: Animal Learning and Cognition suggests that’s not quite right. (Here’s a PDF of the paper, if you’re curious.) Stress increases our desire for a reward, but it doesn’t necessarily cause us to enjoy that reward more than people who aren’t under stress, reports Eva Pool, a doctoral student at the University of Geneva.
Here’s the way Pool went about her study, according to a release from the American Psychological Association:
For the experiment, researchers recruited 36 university students … who said they love chocolate. To induce stress, the researchers asked students to keep one hand in ice-cold water while being observed and videotaped. Another group immersed a hand in lukewarm water. Ten minutes before and 30 minutes after the task, researchers collected samples of the participants saliva and tested them for levels of cortisol, a hormone involved in stress response. Following the stress conditioning, all participants had to press a handgrip for the chance to smell chocolate when they saw a certain symbol. The researchers measured the amount of effort participants invested for a chance to smell the chocolate, and asked participants how pleasant they found the odor.
So those in the stress condition had to work harder to earn the chance to take in the smell of chocolate, and yet both groups said they enjoyed the scent about the same. Maybe this is because smelling chocolate is not nearly as fun as eating chocolate, and who really enjoys smelling chocolate all that much, anyway? But this is the human version of something called the Pavlovian-instrumental transfer test, which had previously been used on rats to measure stress, desire, and subsequent pleasure in a similar way. And the idea Pool is proposing here does make real-life sense: For instance, when I was frantically finishing up work in order to go on vacation before Christmas, I inhaled a pack of chocolate almonds and barely even tasted them. The APA release notes that the researchers would like to follow up this finding with studies that more closely resemble real-life scenarios, so they’re welcome to use my self-report.