This is the scene. It's Christmas Day. You spent weeks shopping for friends and family and finally it's time to open the presents under the tree.

It might be a moment of excited anticipation or if present buying isn't your thing, utter dread as they slowly unwrapped the box to reveal.

A nose hair trimmer, the wrong sized socks, a book they've already read, a bottle of gin for the tea-toteller.

Even if you don't celebrate Christmas, presents for any occasion can be a wonderful way to express your love and gratitude, but they can also be a total minefield.

So what's the psychology behind gift giving and does science have any clues as to how we can do it better? From the Guardian, I mean, and this is Science Weekly.

Julian Givi, you're an assistant professor in marketing at West Virginia University.

You spent some time researching the psychology of gift giving.

Almost every culture around the world exchanges gifts in one way or another. It clearly serves an

important function. So why do we give presents in the first place? The first reason

is because we want to make other people happy, right?

If you think about this kind of most genuine reason you can give someone a gift.

You have a very altruistic motive.

Secondly, this one's maybe a little bit more surprising, and it's definitely not one I predicted when I started

studying gift giving we sometimes give gifts because there's some selfish reasons

right we might give a nice gift to someone because we want them to look at us

positively right we might want to look like a thoughtful person.

And third, somewhere kind of in between the two is the motivation that's driven by a desire to kind of

improve both of our welfare, so to kind of grow the relationship between me and the recipient, right?

And then kind of the fourth reason it has to do is social norms. Christmas we have to give gifts to those around us, you know, Hanukkah, same same type of thing and there's this norm we have to follow

saying that okay whenever these things pop up we have to give gifts and so we kind of do so to

follow the norm. One thing you focus on in particular is mismatched presents, something that we all dread when you give an unwanted present or maybe worse, you sort of have to pretend you love something you've received when you hate it.

How much money do we all spend on these unwanted presents?

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