Michael Merzenich, PhD

February 10, 2022

As the Bard said, “Love is a many splendored thing.” Appropriately, that quote is from Shakespeare’s sonnets, not his plays. Although, as a scientist, I can talk about the brain chemistry of love, I am also certain that love can be as much poetry as chemistry.

With Valentine’s Day fast approaching, let’s look at both the chemical brain processes that correspond with love, and what we can do to prepare for love and to be loving.

When You’re Falling in Love

When you are falling in love, it’s as though a chemical storm has been unleashed in the brain. The brain’s neuromodulatory system is rapidly pumping out large quantities of dopamine and noradrenaline. It’s that chemical explosion that makes you feel excited and warm all over.

Dopamine is a brain chemical associated with reward. It’s the brain’s way of adjusting to some good result that should be accentuated and remembered. In this case, dopamine gets released when I receive something wonderful from you — as I do in the association we call love — or, when I have the pleasure of giving you something. Love is a mutual giving and receiving of something wonderful.

The same system is releasing noradrenaline because of the newness and excitement of it all. It’s the brain’s way of accentuating that there is something novel going on that should be noticed. It makes you feel brighter and more alive. There is almost no time in your life when you feel more alive than when you are falling in love.

Craving Your Beloved

As the relationship deepens, the pleasure that you associate with love makes you crave more.

One of the wonderful things about dopamine is that it is initially only released at the time of the excitement, but then the brain is smart enough to release it in advance of the excitement — in anticipation of the hug, the kiss, or the presence of the beloved.

You actually begin to feel warm before the moment of connection. That contributes to you craving it. It becomes an addiction. You want to see that person again — to connect again.

I should let you know that these chemical systems also kick in over things you love. Perhaps you really enjoy a martini after a hard day at work. Initially, it’s because of the way it makes you feel (more relaxed), but after a while you get some of that feeling of relaxation from the first sip — long before the alcohol has done its job — because of your anticipation of its effects.