MELISSA BLOCK, HOST:
Maybe you don't need the reminder or maybe you'd like to forget. Either way, it is Valentine's Day and we're going to mark the occasion with some sweet psychology.
NPR's Allison Aubrey reports on how we pick chocolates and what it might say about how we pick partners.
ALLISON AUBREY, BYLINE: Let's start with chocolate. If you think your likes and dislikes are set in stone, you prefer milk, dark or maybe spiked with espresso, well, researcher Ed O'Brien, he knows your type.
ED O'BRIEN: We think that we do have these kind of ingrained preferences. So, if I'm a dark chocolate person, I think of myself as, you know, I will always like dark chocolate more than others.
AUBREY: O'Brien is a PhD student in psychology at the University of Michigan. He's long suspected, though, that we're more impressionable than we realize. To test his hunch, O'Brien devised a chocolate taste test to see if he could manipulate people's preferences.
O'BRIEN: Once you're in the moment, so once you're in this taste test that we had, you can often kind of push around people's preferences. And even though I see myself as a dark chocolate person, I may pick something else when I'm actually in the moment to choose.
AUBREY: The moment of choice is key and turns out it's all about how you offer the chocolate. I tried a similar taste test on some friends when they came over for book club the other night. Maureen Conley, Karen Schleifer, Cindy Merz, Lauren Dikeman(ph), and Sue Gander(ph), knew I was up to something as I passed around little bowls of chocolate.
UNIDENTIFIED WOMAN #1: Is it all about the color of the wrapper?
AUBREY: Nope, it's not.
Before I go any further, I should tell you the chocolate tasting was set up to taste a particular theory. O'Brien thinks there's something special about ending or last chances.
O'BRIEN: I think in everyday life we do have this general expectation that, yeah, we save the best for last. And, you know, when we go to a concert, we hear the best song at the end of the show.
AUBREY: Or, if we know the next installment of a favorite book or series is the last, say, the last Harry Potter movie, we get a little more jazzed about it.
O'BRIEN: When people are given awareness that something is about to end, they're kind of motivated to make the most of that experience.
AUBREY: Even if it's something as simple as a chocolate?
Do you like it?
UNIDENTIFIED WOMAN #1: It's yummy.
(SOUNDBITE OF LAUGHTER)
UNIDENTIFIED WOMAN #2: Mmm, perfect balance it seems like...
AUBREY: Now, I only had five tasters, but O'Brien and his team had about 50, mostly students they approached on the University of Michigan campus. Each agreed to try a bunch of different kinds of Hershey Kisses from almond to caramel to dark, and then rate their favorites.
O'BRIEN: First, we wanted to make sure that they couldn't see how many we were about to give them. Because if they know there's going to be five, then we can't really surprised that by saying it's about to end. So, we had a big bag of candy that was covered from the outside, so you couldn't really see what was in it or how many were in it.
AUBREY: And O'Brien explained the tasters who were offered the chocolate and then told when they'd come to the last one, more often than not, said the last was the best.
O'BRIEN: The majority of people who all of a sudden ate that last chocolate chose that last chocolate as their favorite, even though we kind of randomly distributed the flavors.
AUBREY: And something similar happened in my living room.
So this is the very last one.
UNIDENTIFIED WOMAN #4: OK. I don't get anymore after this?
(SOUNDBITE OF LAUGHTER)
AUBREY: No, this is it.
UNIDENTIFIED WOMAN #4: Mmm, dark and rich.
(SOUNDBITE OF LAUGHTER)
AUBREY: Mine was a very small experiment, but I did find a small bias towards the last chocolate eaten.
UNIDENTIFIED WOMAN #5: I might eat the whole thing.
AUBREY: So, the last is definitely a favorite.
UNIDENTIFIED WOMAN #5: It was definitely my favorite.
AUBREY: Now this is where the romance comes in. O'Brien described to me a similar study he and his colleagues did, asking people to rate online dating profiles. He found that there was a big advantage when a person's profile was introduced as the last one you'll see today.
O'BRIEN: That person all of a sudden became more attractive. They seemed more compatible with you, reaping those similar benefits as you would in the chocolate study.
AUBREY: So the last person you read about it may be the one to decide to reach out to. Now, if Brad Pitt or a fancy Belgian chocolate entered the picture, I bet the bias towards the last falls apart very quickly. But all things being equal, well, it may be beneficial in love or chocolate to be judged last.
Allison Aubrey, NPR News.
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ROBERT SIEGEL, HOST:
This is ALL THINGS CONSIDERED from NPR News.