If you’ve been to a wedding recently—and it’s August, so who hasn’t?—you’ve seen somebody cry. But why? Weddings are supposed to be happy occasions. Crying is supposed to be a sad emotion. Why do we cry when we’re happy?
Here’s the thing: my teeny-tiny almond-sized hypothalamus can’t tell the difference between me being happy or sad or overwhelmed or stressed. Yours can’t tell the difference, either. All it knows is that it’s getting a strong neural signal from the amygdala, which registers our emotional reactions, and that it must, in turn, activate the autonomic nervous system.
So you cry when you’re happy really for the same reasons you cry when you’re sad. And crying in general has a couple of different functions. Tears help people recognize sad emotions in other people, says neuroscientist Mark Fenske. At ASAP Science, they have a rundown of why we cry.
Crying can also result in feelings of empathy and bonding with those around you. So when everybody at the wedding cries together, even if they don’t really know why they’re crying, they feel connected to one another in their weepy joy.
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