How does your biochemistry affect your relationship? Are there ways to foster the inner chemicals of love to keep things feeling fresh and vibrant? Today we’re talking about the big “O” - Oxytocin - and its impact on how we fall into love, and keep love going. In other earlier episodes on the show, we’ve talked about oxytocin, and oxytocin versus dopamine - and it seemed like it was time to go straight to the source of much of what we know about how oxytocin works. Today’s guest is Sue Carter, Director of the Kinsey Institute, and Rudy Professor of Biology at Indiana University. Sue was the first person to figure out oxytocin’s role in how we bond with our partners - so if you hear people talking about this “love chemical” - they’re probably talking about her work or work that’s based on her work. We’re going to chat about what we know about oxytocin, what we don’t know, and how to use the science to help you improve things with your partner. The Love Hormone: Oxytocin is often seen as the ‘love hormone’. It was first discovered to be involved in love in the early 1970’s when it was found to be present in the birth process. Since that time it has been proven to play a key role in birth, as well as in the bonding of mother and child. More recently it has been discovered that oxytocin affects our brains, and is involved in the biological and neurological system of attachment between parents and children, and between adult partners. Why is oxytocin so important in successful long term relationships? Anything that lasts a long time in human behavior has to have a biochemical or biological basis. There has to be a mechanism that allows us to fall in love, one that helps keep us together, as well as a mechanism for allowing break ups to happen. The question of why oxytocin is so important is complicated to answer, but the short answer is that it is a mammalian hormone with an ancient biochemistry (meaning it existed before the emergence of mammals) and it is reused many times for many purposes. The most important things in a human life require oxytocin to be present. This includes birth, caring for offspring, finding a mate, creating a social bond with our partners, and restoration and healing in the face of stress. All mammals have a very similar brain stem.  The basic biology of pair bonding and of attachment is possible using old neural mechanisms and is housed in old parts of our brain - the parts of our brain stem which we share with all other mammals. Many believe that the most important organ for connection is our brain. In fact, Woody Allen once said, that the brain is his “second favorite sex organ”.  The brain is directly engaged in the process of both falling in love and experiencing positive forms of sex. Fostering oxytocin production: We can get low level oxytocin production through simple social behaviors- interacting, play, being in a socially safe place, and engaging with others. The most reliable way to release higher levels of oxytocin in humans is via sexual behavior, specifically orgasm. Another activity with high oxytocin production is birth - in which the hormone is released in repeated bursts. Parent and child - All human babies need a caretaker, and it appears that oxytocin is critically involved in the bonding and attachment necessary to keep children cared for. Attachment behaviors found between parents and children produce similar oxytocin producing results between two adults. For example, it is a fact that the human breast has a monosynaptic connection between the breast and hypothalamus- meaning there is a direct route from the breast to the brain*. This route is not limited to nursing- any kind of breast stimulation has the potential to release oxytocin with other stimulation, if in the right context. *Men also have this same nipple neural network. We have a biology that is beautifully attuned to allow us to attach to people that are safe, and people that we have good potential to become long term partn