Exploring the Biochemistry of Love

Valenetine’s Day is here, and even over in McCardell Bicentennial Hall, talk has turned towards love. This past Tuesday, Philip Battell/Sarah Stewart Professor of Chemistry and Biochemistry Jeff Byers gave a talk on “Love, Pain, and Chocolate: Musings of a Structural Scientist on the True Meaning of Valentine’s Day.”

But Byers admits in an email that “the talk I give is mostly a sneaky way to get people to think in general about how and why drugs work.”

He discussed opiates (“to show how and why very similar looking molecules can have very similar effects, and the evolutionary reasons why this is the case”) then ranged over the active compounds in chocolate – caffeine and phenethyl amine – and discussed a molecule called anandamide, which activates cannabinoid receptors, which are associated with pain and pleasure.

Hopefully those who attended ended up seriously contemplating “how and why drugs work.” Introducing even a single chemical into the complex system that is our body can have dramatic repercussions. It’s a powerful idea.

Maybe less apparent, though perhaps more profound: the chemicals that our own body creates can directly influence our behavior, our interactions with one another.

Let’s run with the Valentine’s Day theme here. Pause for a second to ponder this: love is not a chemical introduced into our bodies from the outside.

It is an emotion that wells up from within. We’ve all felt that heartstring tug, perhaps particularly acute this time of year. But what’s it all about? Why and how does it work?

A quick Google search (keyword: “the biochemistry of love”) yields an interesting array of articles. I was particularly intrigued by one published by the Nature Publishing Group, “The biochemistry of love: an oxytocin hypothesis.”

The authors, Sue Carter and Stephen W. Porges argue that “love is clearly not ‘just’ an emotion; it is a biological process … Social interactions between individuals … trigger cognitive and physiological processes that influence emotional and mental states.”

Love is a biological process, and biology is chemistry on a grand scale. So love is, at its most fundamental level, a chemical process.

The chemicals are oxytocin, a nine-amino acid peptide synthesized in the hypothalamus, and its partner in crime, vasopressin. They are two peptides – proteins, chains of amino acids – associated with the numerous behaviors and emotions that can be qualified as “love.”

And not just “romantic love.” Their presence is proven to be associated with parenting, protective behaviors and long-lasting reciprocal relationships – all associated with a different form of love. Agape, if you will.

Which is to say that the macromolecule chemistry of our own bodies influences our behavior towards those closest to us.

What’s the lesson from that statement, the takeaway?

Here it is: Science can help us understand, at a fundamental level, who and what we are. It can help to explain why we do the things we do. Which is why each and every one of us, regardless of whether we attended Byers’ talk, should take an interest in “the science of us.”

What frequently turns people away from science is that it is jargon-intensive.  There are lots of factoids. But taking an interest in science is less about learning all the factoids and more about taking an interest in the thought process, the scientific method.

“The essence of science has more to do with its motivations and methods than with its conclusions,” explained Joseph Putko ’13, a physics major, in an email. “‘Scientific literacy’ has more to do with a thought process than with knowing scientific ‘facts.’  The primary motivation of science is wanting to know. The primary method is questioning.  So, scientific literacy is sort of a marriage between wonder and skepticism.”

Carl Sagan was a renowned science writer who argued passionately for a greater appreciation for and understanding of science in society.

He wrote: “Science invites us to let the facts in, even when they don’t conform to our preconceptions. It counsels us to carry alternative hypotheses in our heads and see which ones best match the facts. It urges on us a fine balance between no-holds-barred openness to new ideas, however heretical, and the most rigorous skeptical scrutiny of everything — new ideas and established wisdom. We need wide appreciation of this kind of thinking. It works. It’s an essential tool for a democracy in an age of change. Our task is not just to train more scientists but also to deepen public understanding of science.”

Science gives us a window into a very profound level of our being. So this Valentine’s Day, whether caught up in romantic endeavors or bemoaning a lack of them, we should pause and think about Byers’ “how and why.”   It’s not just for the select few on this campus who attended the Byers lecture. The inner workings of our being concern us all.