Though we may feel pangs of love in our hearts, the actual signs of this strong emotion resonate in our brains. And thanks to modern science and technology, we can physically observe love’s neurobiological effects. Dr. Robert Weiss is a clinical sexologist and practicing psychotherapist who maps the mind and studies love, sex and addiction.

WAM: Does love live in a certain part of our brain—and, if so, which part—and what is happening to that part of the brain when we fall in love?

DR. WEISS:: Traditionally, love is thought of as living in the heart, and many people claim to experience the emotion of love within their chest. This is understandable, as our hearts typically beat faster and we tend to feel ‘butterflies’ when we deeply fantasize about or encounter a romantic partner. In reality, however, love resides in the brain. And when I say brain, I actually do mean the blood and guts organ.

We know this because functional magnetic resonance imaging (fMRI) scans can be used to measure activity within the brain. When part of the brain is activated (by a thought, a movement, a drug, an emotion, etc.), blood flow to that region is increased and fMRI scans clearly show where in the brain this occurs. Using this technology, monitoring and mapping things like sexual arousal and romantic love is actually a relatively straightforward endeavor.

Generally speaking, research tells us that intense romantic love activates dopamine-rich regions in the brain, in particular the striatum. (The striatum includes the nucleus accumbens, also known as the brain’s pleasure or rewards center.) Intense romantic love also activates regions of the brain associated with motivation to acquire a reward, primarily the insula, which ‘gives value’ to pleasurable, life-sustaining activities (to make sure we continue to engage in them). The release of dopamine in the striatum creates a sensation of “I want.” The release of oxytocin in the insula creates a sensation of “I want … to bond.” What this means, in a nutshell, is that individuals who are in love are strongly motivated to be with the person they love because that action creates sensations of pleasure, contentment, and well-being.

WAM: Is there a difference in the brain between romantic love and sexual attraction?

DR. WEISS: Absolutely. As stated above, research clearly shows that intense romantic love activates the portion of the brain that includes the pleasure/rewards center. Research also shows that intense sexual attraction has a similar action. This means that both sexual attraction and lasting love cause the release of dopamine and create the experience of pleasure.

Further research, however, shows that sexual attraction and lasting love eventually diverge in the brain, with longer-term love causing the release of oxytocin (which causes emotional bonding).

Interestingly, women release oxytocin (bonding hormones) during sex which means they tend to feel a bond simply having been sexual. Men can emotionally bond to another during sex–or not–but healthy women tend to bond unconsciously.

The ultimate takeaway here is that in our brains lasting love has an inherent value that sexual attraction does not. Both feelings activate the pleasure/rewards center of the brain, but only love activates the release of oxytocin, which bonds us together – child and parent, lover and partner.

Interestingly, the striatum is the area of the brain most closely associated with the formation of addiction. In fact, addictive substances and activities all rather thoroughly stimulate this segment of the brain. As such, it is hardly surprising that some people (i.e., love addicts) might get hooked on the early, super-exciting stage of relationships. After all, this early stage of a relationship causes the release of dopamine, adrenaline, oxytocin, serotonin, and various other endorphins—the same basic neurobiological stimulation that we get with cocaine, heroin, sexual activity, gambling, and other addictive substances and behaviors.

WAM: Since love lives in that part of the brain that is involved in addiction, does that mean it’s unhealthy for us—leading us on to “get hooked” on someone? How much control do we have over that part of our brain?

DR. WEISS: We are wired to experience pleasure/rewards in the brain related to life-sustaining activities. Eating is pleasurable. Sex is pleasurable. Intimate connections are pleasurable. Nesting is pleasurable. All are necessary to both individual survival and survival of the species. If we don’t eat, we die. If we don’t have sex, we don’t have babies. If we don’t experience intimate connection to our partners and our children, we won’t care for our children and they will die. So pleasurable sensations actually drive us toward successful survival.

More specifically, if we did not experience the initial stages of intense attraction during early romance (technically referred to as limerence), we would never stay with another person long enough to get to know them and to assign value (i.e., to experience love) to our relationship with them. We need this addiction-like stage of sexual and romantic attraction. It is a necessary step on the road to long-term love.

WAM: Why is limerence necessary from the standpoint of evolution?

DR. WEISS: Limerence is the dopamine-fueled early-relationship stage of relationships where everything the other person says or does is absolutely wonderful. Even the stuff that may eventually annoy us is likely to seem ‘cute’ and ‘quirky’ and ‘fun’ at this stage. We think about the other person all the time because it makes us happy. We may even obsess a little bit, with our friends and family wishing we would talk about something else for a while. We might even look ‘addicted’ to the other person, and this is all not only normal but necessary because it keeps us attached to the other person long enough to find out if he or she is (or is not) a good long-term fit. The downside, as mentioned above, is that some people can get hooked on the high of limerence, compulsively chasing it over and over. This compulsive pattern can be frustrating and counterproductive, as it prevents the formation of lasting intimate sexual/romantic bonds rather than facilitating those bonds.

WAM: What have brain scans revealed about human happiness? Is love involved in happiness?

DR. WEISS: In the brain, happiness can look like sexual attraction (living in the insula) and longer-term love (living in both the insula and the striatum). This is probably not surprising after the explanation given above. Unsurprisingly to most readers is the simple fact that people who feel intimately connected are generally much happier in life. They also tend to live longer and do better handling the obstacles that life puts in their path. Stated very simply, we are happier and more successful in all aspects of life when we feel ‘a part of’ than when we are when we feel ‘apart from.’ And love and romance, in all their glorious craziness, are the path to such happiness, even though that path can be littered with pitfalls as we bumble along the road to connection.