In honor of Valentine’s Day I’ve done a little research on the biology of love and sex and its effects on the brain. You may be surprised to learn that there is not too much dissimilarity between the male and female brain during sex, and the effects on our neurotransmitters can liken the experience of orgasm to feelings of being high. Interestingly, though, the same neurotransmitters released during sex are also released throughout the process of falling in love and it’s those chemicals that make people act dopey in the initial stages of love. So if the reaction on the brain is so similar, why are there so many men and women who never call after a night of passion? And can sex be your drug?
Falling in love is not a phenomenon caused by Cupid’s arrow. Physical and chemical reactions occur in our bodies and brains when we see, touch, or taste things that appeal to us, such that falling in love is actually a very scientific process. Anthropologist Dr. Helen Fisher of Rutgers University explained in a lecture at the 2004 American Psychiatric Association’s annual meeting, that romantic love is not an emotion. Rather, it’s a motivation system, it’s a drive, it’s part of the reward system of the brain. Meeting someone to whom you are attracted, falling in love with that person, and having lifelong companionship certainly brings a string of rewards, but what’s our motivation during sex? Um, duh…to activate the reward circuitry of our brains via mind-blowing orgasms.
Chemically, our sexuality starts with the sex hormones testosterone and estrogen which control our libido. Without them we would be asexual, unable to reproduce, and our species probably would have become obsolete long ago. That’s sex drive in a nutshell—or, the lust part of being human.
Physically, the process of sexual stimulation looks something like this: Signals are sent from the limbic lobe of the brain via the nervous system to the pelvic region. These signals tell the blood vessels to dilate. This dilation creates a blood flow to the nether regions. The vessels then close leaving those tissues (in men and women) engorged. As this occurs, our brains release norepinephrine and dopamine, the neurotransmitters that tell our bodies that the feelings are good and pleasurable. We also experience a rise in these chemicals as we spend time with a potential lover getting to know him or her; it just doesn’t happen as quickly as the surge you get rolling around in the sack. While falling in love may take months or years for some couples, the act of sex mimics the release of these chemicals in a very brief time. And you’ll crave more and more of someone until you experience a release of oxytocin (that comes with orgasm) and is known as the bonding chemical. Oxytocin is vital to your ability to make long-term relationships and is the reason for the cuddle-effect some people experience post-coitus.
In both sexes during orgasm, the brain region behind the left eye, called the lateral orbitofrontal cortex and known as the seat of reason and behavioral control, shuts down. So when you orgasm, you lose control. Hence the K-Y commercials showing fireworks, circus acts, then disheveled couples left trying to catch their breath. Dr. Gert Holstege, a neuroscientist at the University of Groningen in the Netherlands stated, after scanning the brains of numerous people having sex, that the brain during an orgasm looks much like the brain of a person taking heroin. He stated that 95 percent is the same. If the high is so good, why are there not more sex addicts? It all comes down to the natural regulation of the chemicals in your brain.
Orgasms and addictive substances/behaviors have two things in common: producing an initial pleasurable experience (a high) followed by a hangover. The aftereffects (hangover), is simple biology—your body returning to balance. Post-orgasm, your dopamine returns to normal, thus creating the hangover. For most people, this occurs without noticing. Normally there are no evident withdrawal symptoms, although a sexual hangover can linger for up to two weeks. During this time our brain proposes logical reasons to explain our relationship disharmony. Suddenly a lover appears unattractive or irritating or is just simply unreasonable. I got what I wanted now how the hell do I get away from this person as quickly as possible? Hence, never calling again.
No doubt rollercoaster levels of dopamine can send us running out the door with our pants around our ankles, but there’s also something that allows us to be monogamous: the bonding hormone I mentioned earlier—oxytocin. Without it, we could not stay in love. The heartwarming, loving, can’t-live-without-you aspects of love are due to oxytocin. Oxytocin is the hormone associated with nurturing and has various functions in the body, like inducing labor contractions and causing lactation. It is the hormone that serves to bond us to our mate, if for no longer than first allowing us to bond with our children.
So I can end this article in no better way than quoting Dr. Fisher who once said, “Don’t copulate with people you don’t want to fall in love with because indeed you may do just that.” And a high like that should last longer than any drug.