In the past few years scientists have been discovering amazing facts about our brains. We know that already in the womb many of the key pathways betweens nerves have already been made. By the time a child is three years old his or her brain is 85% wired. By the end of adolescence, the brain has 10 billion neurons jammed up against one another. Electricity flowing through the neurons makes the brain work. There are more than 100 trillion synapses, the connections between the neurons that make the brain function. Then there are the neurochemicals that bathe the neurons and the synapses all the time, moving messages through the brain.
Three of these neurochemicals – oxytocin, vasopressin, and dopamine – are very involved in our sexual interest and behavior. When we look at what these chemicals do, we see some of the answers of Science to the question, “What is sex for?”
- Sex is to join a man and a woman for life. When two people have sexual intercourse, or when they just touch intimately, oxytocin is released into their brains – even if the touch is just a 20-second hug. Oxytocin is present in both male and female, but it is primarily active in females. When it is released into the woman’s brain, it does two things: it increases her desire for more touch and it causes her to bond to the man with whom she is having intimate physical contact. In sexual intercourse, her brain is flooded with oxytocin, creating deeper bonding with each subsequent physical union. Oxytocin is like an emotional super-glue, bonding the man and woman together. The neurochemical responsible for the male brain response is vasopressin. It bonds a man to his mate and creates an attachment to his children.
- Sex is to build trust between husband and wife. Oxytocin also produces in the woman a feeling of trust in the man with whom she is being sexually intimate. Vasopressin has the same effect on the man in relation to the woman.
- Sex is for pleasure, to make us feel good. The neurochemical dopamine is also known as the “reward signal.” It pours into the brain when we do something important or exciting or rewarding. It makes us feel good, and we want to repeat the action. Sex is one of the very strongest generators of the dopamine reward; sex is rewarded by floods of dopamine into the brain.
Science shows us that we have been designed to be sexually monogamous, to be with one mate for life. We already know this from the Bible, and in the Bible we have instructions for living this way.
What happens, then, when two young people who are not married are sexually intimate?
They also experience bonding, because of the “emotional super-glue”. They experience the trust. The sex feels good. But when the relationship then ends, the emotional pain is real, because real brain chemicals have acted on real brain cells, causing those brain cells to bind them together. If this happens often, it can leave one feeling dead inside, lost and hurt, unable to love adequately, feeling unworthy of being loved.
Although sex makes one trust a partner, that trust may be misplaced.
The sex itself may lose its excitement.
Sex with multiple partners damages our inbuilt bonding mechanism. Vasopressin no longer has the same power to bond a man to a woman, or to his children. Sex rarely holds people together unless they are married. This, too, we know – from the Bible, and from experience.