Want to boost your mood? Talk to a stranger

"Commuting is one of the worst activities for human happiness that researchers have discovered."

So says Michael Norton, a psychology professor at Harvard Business School.

But if you're commuting by airplane or public transit, Norton said there's an easy way to make yourself happier: talk to the stranger next to you.

If that sounds like the opposite of what you want to do on the bus, you're not alone. Norton said most of us assume that a conversation with a stranger will be unpleasant.

But according to him, research indicates the opposite.

Norton said that the University of Chicago asked a group of commuters to force themselves to chat with the stranger next to them. Guess what? They were happier than the group that kept their heads down and their earbuds on.

"We care what other people think of us," said Norton. "When we start talking to someone, we really, really hope they kind of like us, that they think we're interesting and smart and funny and nice."

The key reason we become happier when talking to strangers, he said, is that we try. 

"In that process of trying, we do things like smile and engage and laugh," said Norton. "Those things actually turn out to make us happy ourselves. It's almost like you fake it to be nice and happy and then you get feedback to yourself that you're actually having a nice and happy conversation."

Not only that but, "When the other person smiles back at us, that's a whole other source of happiness," he said.

"We really do underestimate the extent to which people make us happy," Norton told Sook-Yin Lee of DNTO. "People are an incredible source of meaning and happiness in our lives and we're underutilizing them in terms of making ourselves happy on a daily basis."

So don't listen to your mom. Talk to strangers!